python-3.6.zip added from Github

README.cosmo contains the necessary links.

third_party/python/Lib/test/test_importlib/__init__.py

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+import os
+from test.support import load_package_tests
+
+def load_tests(*args):
+    return load_package_tests(os.path.dirname(__file__), *args)

third_party/python/Lib/test/test_importlib/__main__.py

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+from . import load_tests
+import unittest
+
+unittest.main()

third_party/python/Lib/test/test_importlib/abc.py

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+import abc
+import unittest
+
+
+class FinderTests(metaclass=abc.ABCMeta):
+
+    """Basic tests for a finder to pass."""
+
+    @abc.abstractmethod
+    def test_module(self):
+        # Test importing a top-level module.
+        pass
+
+    @abc.abstractmethod
+    def test_package(self):
+        # Test importing a package.
+        pass
+
+    @abc.abstractmethod
+    def test_module_in_package(self):
+        # Test importing a module contained within a package.
+        # A value for 'path' should be used if for a meta_path finder.
+        pass
+
+    @abc.abstractmethod
+    def test_package_in_package(self):
+        # Test importing a subpackage.
+        # A value for 'path' should be used if for a meta_path finder.
+        pass
+
+    @abc.abstractmethod
+    def test_package_over_module(self):
+        # Test that packages are chosen over modules.
+        pass
+
+    @abc.abstractmethod
+    def test_failure(self):
+        # Test trying to find a module that cannot be handled.
+        pass
+
+
+class LoaderTests(metaclass=abc.ABCMeta):
+
+    @abc.abstractmethod
+    def test_module(self):
+        """A module should load without issue.
+
+        After the loader returns the module should be in sys.modules.
+
+        Attributes to verify:
+
+            * __file__
+            * __loader__
+            * __name__
+            * No __path__
+
+        """
+        pass
+
+    @abc.abstractmethod
+    def test_package(self):
+        """Loading a package should work.
+
+        After the loader returns the module should be in sys.modules.
+
+        Attributes to verify:
+
+            * __name__
+            * __file__
+            * __package__
+            * __path__
+            * __loader__
+
+        """
+        pass
+
+    @abc.abstractmethod
+    def test_lacking_parent(self):
+        """A loader should not be dependent on it's parent package being
+        imported."""
+        pass
+
+    @abc.abstractmethod
+    def test_state_after_failure(self):
+        """If a module is already in sys.modules and a reload fails
+        (e.g. a SyntaxError), the module should be in the state it was before
+        the reload began."""
+        pass
+
+    @abc.abstractmethod
+    def test_unloadable(self):
+        """Test ImportError is raised when the loader is asked to load a module
+        it can't."""
+        pass

third_party/python/Lib/test/test_importlib/builtin/__init__.py

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+import os
+from test.support import load_package_tests
+
+def load_tests(*args):
+    return load_package_tests(os.path.dirname(__file__), *args)

third_party/python/Lib/test/test_importlib/builtin/__main__.py

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+from . import load_tests
+import unittest
+
+unittest.main()

third_party/python/Lib/test/test_importlib/builtin/test_finder.py

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+from .. import abc
+from .. import util
+
+machinery = util.import_importlib('importlib.machinery')
+
+import sys
+import unittest
+
+
+@unittest.skipIf(util.BUILTINS.good_name is None, 'no reasonable builtin module')
+class FindSpecTests(abc.FinderTests):
+
+    """Test find_spec() for built-in modules."""
+
+    def test_module(self):
+        # Common case.
+        with util.uncache(util.BUILTINS.good_name):
+            found = self.machinery.BuiltinImporter.find_spec(util.BUILTINS.good_name)
+            self.assertTrue(found)
+            self.assertEqual(found.origin, 'built-in')
+
+    # Built-in modules cannot be a package.
+    test_package = None
+
+    # Built-in modules cannot be in a package.
+    test_module_in_package = None
+
+    # Built-in modules cannot be a package.
+    test_package_in_package = None
+
+    # Built-in modules cannot be a package.
+    test_package_over_module = None
+
+    def test_failure(self):
+        name = 'importlib'
+        assert name not in sys.builtin_module_names
+        spec = self.machinery.BuiltinImporter.find_spec(name)
+        self.assertIsNone(spec)
+
+    def test_ignore_path(self):
+        # The value for 'path' should always trigger a failed import.
+        with util.uncache(util.BUILTINS.good_name):
+            spec = self.machinery.BuiltinImporter.find_spec(util.BUILTINS.good_name,
+                                                            ['pkg'])
+            self.assertIsNone(spec)
+
+
+(Frozen_FindSpecTests,
+ Source_FindSpecTests
+ ) = util.test_both(FindSpecTests, machinery=machinery)
+
+
+@unittest.skipIf(util.BUILTINS.good_name is None, 'no reasonable builtin module')
+class FinderTests(abc.FinderTests):
+
+    """Test find_module() for built-in modules."""
+
+    def test_module(self):
+        # Common case.
+        with util.uncache(util.BUILTINS.good_name):
+            found = self.machinery.BuiltinImporter.find_module(util.BUILTINS.good_name)
+            self.assertTrue(found)
+            self.assertTrue(hasattr(found, 'load_module'))
+
+    # Built-in modules cannot be a package.
+    test_package = test_package_in_package = test_package_over_module = None
+
+    # Built-in modules cannot be in a package.
+    test_module_in_package = None
+
+    def test_failure(self):
+        assert 'importlib' not in sys.builtin_module_names
+        loader = self.machinery.BuiltinImporter.find_module('importlib')
+        self.assertIsNone(loader)
+
+    def test_ignore_path(self):
+        # The value for 'path' should always trigger a failed import.
+        with util.uncache(util.BUILTINS.good_name):
+            loader = self.machinery.BuiltinImporter.find_module(util.BUILTINS.good_name,
+                                                            ['pkg'])
+            self.assertIsNone(loader)
+
+
+(Frozen_FinderTests,
+ Source_FinderTests
+ ) = util.test_both(FinderTests, machinery=machinery)
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/builtin/test_loader.py

@@ -0,0 +1,108 @@
+from .. import abc
+from .. import util
+
+machinery = util.import_importlib('importlib.machinery')
+
+import sys
+import types
+import unittest
+
+@unittest.skipIf(util.BUILTINS.good_name is None, 'no reasonable builtin module')
+class LoaderTests(abc.LoaderTests):
+
+    """Test load_module() for built-in modules."""
+
+    def setUp(self):
+        self.verification = {'__name__': 'errno', '__package__': '',
+                             '__loader__': self.machinery.BuiltinImporter}
+
+    def verify(self, module):
+        """Verify that the module matches against what it should have."""
+        self.assertIsInstance(module, types.ModuleType)
+        for attr, value in self.verification.items():
+            self.assertEqual(getattr(module, attr), value)
+        self.assertIn(module.__name__, sys.modules)
+
+    def load_module(self, name):
+        return self.machinery.BuiltinImporter.load_module(name)
+
+    def test_module(self):
+        # Common case.
+        with util.uncache(util.BUILTINS.good_name):
+            module = self.load_module(util.BUILTINS.good_name)
+            self.verify(module)
+
+    # Built-in modules cannot be a package.
+    test_package = test_lacking_parent = None
+
+    # No way to force an import failure.
+    test_state_after_failure = None
+
+    def test_module_reuse(self):
+        # Test that the same module is used in a reload.
+        with util.uncache(util.BUILTINS.good_name):
+            module1 = self.load_module(util.BUILTINS.good_name)
+            module2 = self.load_module(util.BUILTINS.good_name)
+            self.assertIs(module1, module2)
+
+    def test_unloadable(self):
+        name = 'dssdsdfff'
+        assert name not in sys.builtin_module_names
+        with self.assertRaises(ImportError) as cm:
+            self.load_module(name)
+        self.assertEqual(cm.exception.name, name)
+
+    def test_already_imported(self):
+        # Using the name of a module already imported but not a built-in should
+        # still fail.
+        module_name = 'builtin_reload_test'
+        assert module_name not in sys.builtin_module_names
+        with util.uncache(module_name):
+            module = types.ModuleType(module_name)
+            sys.modules[module_name] = module
+        with self.assertRaises(ImportError) as cm:
+            self.load_module(module_name)
+        self.assertEqual(cm.exception.name, module_name)
+
+
+(Frozen_LoaderTests,
+ Source_LoaderTests
+ ) = util.test_both(LoaderTests, machinery=machinery)
+
+
+@unittest.skipIf(util.BUILTINS.good_name is None, 'no reasonable builtin module')
+class InspectLoaderTests:
+
+    """Tests for InspectLoader methods for BuiltinImporter."""
+
+    def test_get_code(self):
+        # There is no code object.
+        result = self.machinery.BuiltinImporter.get_code(util.BUILTINS.good_name)
+        self.assertIsNone(result)
+
+    def test_get_source(self):
+        # There is no source.
+        result = self.machinery.BuiltinImporter.get_source(util.BUILTINS.good_name)
+        self.assertIsNone(result)
+
+    def test_is_package(self):
+        # Cannot be a package.
+        result = self.machinery.BuiltinImporter.is_package(util.BUILTINS.good_name)
+        self.assertFalse(result)
+
+    @unittest.skipIf(util.BUILTINS.bad_name is None, 'all modules are built in')
+    def test_not_builtin(self):
+        # Modules not built-in should raise ImportError.
+        for meth_name in ('get_code', 'get_source', 'is_package'):
+            method = getattr(self.machinery.BuiltinImporter, meth_name)
+        with self.assertRaises(ImportError) as cm:
+            method(util.BUILTINS.bad_name)
+
+
+(Frozen_InspectLoaderTests,
+ Source_InspectLoaderTests
+ ) = util.test_both(InspectLoaderTests, machinery=machinery)
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/extension/__init__.py

@@ -0,0 +1,5 @@
+import os
+from test.support import load_package_tests
+
+def load_tests(*args):
+    return load_package_tests(os.path.dirname(__file__), *args)

third_party/python/Lib/test/test_importlib/extension/__main__.py

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+from . import load_tests
+import unittest
+
+unittest.main()

third_party/python/Lib/test/test_importlib/extension/test_case_sensitivity.py

@@ -0,0 +1,46 @@
+from importlib import _bootstrap_external
+from test import support
+import unittest
+
+from .. import util
+
+importlib = util.import_importlib('importlib')
+machinery = util.import_importlib('importlib.machinery')
+
+
+@unittest.skipIf(util.EXTENSIONS.filename is None, '_testcapi not available')
+@util.case_insensitive_tests
+class ExtensionModuleCaseSensitivityTest(util.CASEOKTestBase):
+
+    def find_module(self):
+        good_name = util.EXTENSIONS.name
+        bad_name = good_name.upper()
+        assert good_name != bad_name
+        finder = self.machinery.FileFinder(util.EXTENSIONS.path,
+                                          (self.machinery.ExtensionFileLoader,
+                                           self.machinery.EXTENSION_SUFFIXES))
+        return finder.find_module(bad_name)
+
+    def test_case_sensitive(self):
+        with support.EnvironmentVarGuard() as env:
+            env.unset('PYTHONCASEOK')
+            self.caseok_env_changed(should_exist=False)
+            loader = self.find_module()
+            self.assertIsNone(loader)
+
+    def test_case_insensitivity(self):
+        with support.EnvironmentVarGuard() as env:
+            env.set('PYTHONCASEOK', '1')
+            self.caseok_env_changed(should_exist=True)
+            loader = self.find_module()
+            self.assertTrue(hasattr(loader, 'load_module'))
+
+
+(Frozen_ExtensionCaseSensitivity,
+ Source_ExtensionCaseSensitivity
+ ) = util.test_both(ExtensionModuleCaseSensitivityTest, importlib=importlib,
+                    machinery=machinery)
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/extension/test_finder.py

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+from .. import abc
+from .. import util
+
+machinery = util.import_importlib('importlib.machinery')
+
+import unittest
+import warnings
+
+
+class FinderTests(abc.FinderTests):
+
+    """Test the finder for extension modules."""
+
+    def find_module(self, fullname):
+        importer = self.machinery.FileFinder(util.EXTENSIONS.path,
+                                            (self.machinery.ExtensionFileLoader,
+                                             self.machinery.EXTENSION_SUFFIXES))
+        with warnings.catch_warnings():
+            warnings.simplefilter('ignore', DeprecationWarning)
+            return importer.find_module(fullname)
+
+    def test_module(self):
+        self.assertTrue(self.find_module(util.EXTENSIONS.name))
+
+    # No extension module as an __init__ available for testing.
+    test_package = test_package_in_package = None
+
+    # No extension module in a package available for testing.
+    test_module_in_package = None
+
+    # Extension modules cannot be an __init__ for a package.
+    test_package_over_module = None
+
+    def test_failure(self):
+        self.assertIsNone(self.find_module('asdfjkl;'))
+
+
+(Frozen_FinderTests,
+ Source_FinderTests
+ ) = util.test_both(FinderTests, machinery=machinery)
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/extension/test_loader.py

@@ -0,0 +1,300 @@
+from .. import abc
+from .. import util
+
+machinery = util.import_importlib('importlib.machinery')
+
+import os.path
+import sys
+import types
+import unittest
+import importlib.util
+import importlib
+from test.support.script_helper import assert_python_failure
+
+class LoaderTests(abc.LoaderTests):
+
+    """Test load_module() for extension modules."""
+
+    def setUp(self):
+        self.loader = self.machinery.ExtensionFileLoader(util.EXTENSIONS.name,
+                                                         util.EXTENSIONS.file_path)
+
+    def load_module(self, fullname):
+        return self.loader.load_module(fullname)
+
+    def test_load_module_API(self):
+        # Test the default argument for load_module().
+        self.loader.load_module()
+        self.loader.load_module(None)
+        with self.assertRaises(ImportError):
+            self.load_module('XXX')
+
+    def test_equality(self):
+        other = self.machinery.ExtensionFileLoader(util.EXTENSIONS.name,
+                                                   util.EXTENSIONS.file_path)
+        self.assertEqual(self.loader, other)
+
+    def test_inequality(self):
+        other = self.machinery.ExtensionFileLoader('_' + util.EXTENSIONS.name,
+                                                   util.EXTENSIONS.file_path)
+        self.assertNotEqual(self.loader, other)
+
+    def test_module(self):
+        with util.uncache(util.EXTENSIONS.name):
+            module = self.load_module(util.EXTENSIONS.name)
+            for attr, value in [('__name__', util.EXTENSIONS.name),
+                                ('__file__', util.EXTENSIONS.file_path),
+                                ('__package__', '')]:
+                self.assertEqual(getattr(module, attr), value)
+            self.assertIn(util.EXTENSIONS.name, sys.modules)
+            self.assertIsInstance(module.__loader__,
+                                  self.machinery.ExtensionFileLoader)
+
+    # No extension module as __init__ available for testing.
+    test_package = None
+
+    # No extension module in a package available for testing.
+    test_lacking_parent = None
+
+    def test_module_reuse(self):
+        with util.uncache(util.EXTENSIONS.name):
+            module1 = self.load_module(util.EXTENSIONS.name)
+            module2 = self.load_module(util.EXTENSIONS.name)
+            self.assertIs(module1, module2)
+
+    # No easy way to trigger a failure after a successful import.
+    test_state_after_failure = None
+
+    def test_unloadable(self):
+        name = 'asdfjkl;'
+        with self.assertRaises(ImportError) as cm:
+            self.load_module(name)
+        self.assertEqual(cm.exception.name, name)
+
+    def test_is_package(self):
+        self.assertFalse(self.loader.is_package(util.EXTENSIONS.name))
+        for suffix in self.machinery.EXTENSION_SUFFIXES:
+            path = os.path.join('some', 'path', 'pkg', '__init__' + suffix)
+            loader = self.machinery.ExtensionFileLoader('pkg', path)
+            self.assertTrue(loader.is_package('pkg'))
+
+(Frozen_LoaderTests,
+ Source_LoaderTests
+ ) = util.test_both(LoaderTests, machinery=machinery)
+
+class MultiPhaseExtensionModuleTests(abc.LoaderTests):
+    """Test loading extension modules with multi-phase initialization (PEP 489)
+    """
+
+    def setUp(self):
+        self.name = '_testmultiphase'
+        finder = self.machinery.FileFinder(None)
+        self.spec = importlib.util.find_spec(self.name)
+        assert self.spec
+        self.loader = self.machinery.ExtensionFileLoader(
+            self.name, self.spec.origin)
+
+    # No extension module as __init__ available for testing.
+    test_package = None
+
+    # No extension module in a package available for testing.
+    test_lacking_parent = None
+
+    # Handling failure on reload is the up to the module.
+    test_state_after_failure = None
+
+    def test_module(self):
+        '''Test loading an extension module'''
+        with util.uncache(self.name):
+            module = self.load_module()
+            for attr, value in [('__name__', self.name),
+                                ('__file__', self.spec.origin),
+                                ('__package__', '')]:
+                self.assertEqual(getattr(module, attr), value)
+            with self.assertRaises(AttributeError):
+                module.__path__
+            self.assertIs(module, sys.modules[self.name])
+            self.assertIsInstance(module.__loader__,
+                                  self.machinery.ExtensionFileLoader)
+
+    def test_functionality(self):
+        '''Test basic functionality of stuff defined in an extension module'''
+        with util.uncache(self.name):
+            module = self.load_module()
+            self.assertIsInstance(module, types.ModuleType)
+            ex = module.Example()
+            self.assertEqual(ex.demo('abcd'), 'abcd')
+            self.assertEqual(ex.demo(), None)
+            with self.assertRaises(AttributeError):
+                ex.abc
+            ex.abc = 0
+            self.assertEqual(ex.abc, 0)
+            self.assertEqual(module.foo(9, 9), 18)
+            self.assertIsInstance(module.Str(), str)
+            self.assertEqual(module.Str(1) + '23', '123')
+            with self.assertRaises(module.error):
+                raise module.error()
+            self.assertEqual(module.int_const, 1969)
+            self.assertEqual(module.str_const, 'something different')
+
+    def test_reload(self):
+        '''Test that reload didn't re-set the module's attributes'''
+        with util.uncache(self.name):
+            module = self.load_module()
+            ex_class = module.Example
+            importlib.reload(module)
+            self.assertIs(ex_class, module.Example)
+
+    def test_try_registration(self):
+        '''Assert that the PyState_{Find,Add,Remove}Module C API doesn't work'''
+        module = self.load_module()
+        with self.subTest('PyState_FindModule'):
+            self.assertEqual(module.call_state_registration_func(0), None)
+        with self.subTest('PyState_AddModule'):
+            with self.assertRaises(SystemError):
+                module.call_state_registration_func(1)
+        with self.subTest('PyState_RemoveModule'):
+            with self.assertRaises(SystemError):
+                module.call_state_registration_func(2)
+
+    def load_module(self):
+        '''Load the module from the test extension'''
+        return self.loader.load_module(self.name)
+
+    def load_module_by_name(self, fullname):
+        '''Load a module from the test extension by name'''
+        origin = self.spec.origin
+        loader = self.machinery.ExtensionFileLoader(fullname, origin)
+        spec = importlib.util.spec_from_loader(fullname, loader)
+        module = importlib.util.module_from_spec(spec)
+        loader.exec_module(module)
+        return module
+
+    def test_load_submodule(self):
+        '''Test loading a simulated submodule'''
+        module = self.load_module_by_name('pkg.' + self.name)
+        self.assertIsInstance(module, types.ModuleType)
+        self.assertEqual(module.__name__, 'pkg.' + self.name)
+        self.assertEqual(module.str_const, 'something different')
+
+    def test_load_short_name(self):
+        '''Test loading module with a one-character name'''
+        module = self.load_module_by_name('x')
+        self.assertIsInstance(module, types.ModuleType)
+        self.assertEqual(module.__name__, 'x')
+        self.assertEqual(module.str_const, 'something different')
+        self.assertNotIn('x', sys.modules)
+
+    def test_load_twice(self):
+        '''Test that 2 loads result in 2 module objects'''
+        module1 = self.load_module_by_name(self.name)
+        module2 = self.load_module_by_name(self.name)
+        self.assertIsNot(module1, module2)
+
+    def test_unloadable(self):
+        '''Test nonexistent module'''
+        name = 'asdfjkl;'
+        with self.assertRaises(ImportError) as cm:
+            self.load_module_by_name(name)
+        self.assertEqual(cm.exception.name, name)
+
+    def test_unloadable_nonascii(self):
+        '''Test behavior with nonexistent module with non-ASCII name'''
+        name = 'fo\xf3'
+        with self.assertRaises(ImportError) as cm:
+            self.load_module_by_name(name)
+        self.assertEqual(cm.exception.name, name)
+
+    def test_nonmodule(self):
+        '''Test returning a non-module object from create works'''
+        name = self.name + '_nonmodule'
+        mod = self.load_module_by_name(name)
+        self.assertNotEqual(type(mod), type(unittest))
+        self.assertEqual(mod.three, 3)
+
+    # issue 27782
+    def test_nonmodule_with_methods(self):
+        '''Test creating a non-module object with methods defined'''
+        name = self.name + '_nonmodule_with_methods'
+        mod = self.load_module_by_name(name)
+        self.assertNotEqual(type(mod), type(unittest))
+        self.assertEqual(mod.three, 3)
+        self.assertEqual(mod.bar(10, 1), 9)
+
+    def test_null_slots(self):
+        '''Test that NULL slots aren't a problem'''
+        name = self.name + '_null_slots'
+        module = self.load_module_by_name(name)
+        self.assertIsInstance(module, types.ModuleType)
+        self.assertEqual(module.__name__, name)
+
+    def test_bad_modules(self):
+        '''Test SystemError is raised for misbehaving extensions'''
+        for name_base in [
+                'bad_slot_large',
+                'bad_slot_negative',
+                'create_int_with_state',
+                'negative_size',
+                'export_null',
+                'export_uninitialized',
+                'export_raise',
+                'export_unreported_exception',
+                'create_null',
+                'create_raise',
+                'create_unreported_exception',
+                'nonmodule_with_exec_slots',
+                'exec_err',
+                'exec_raise',
+                'exec_unreported_exception',
+                ]:
+            with self.subTest(name_base):
+                name = self.name + '_' + name_base
+                with self.assertRaises(SystemError):
+                    self.load_module_by_name(name)
+
+    def test_nonascii(self):
+        '''Test that modules with non-ASCII names can be loaded'''
+        # punycode behaves slightly differently in some-ASCII and no-ASCII
+        # cases, so test both
+        cases = [
+            (self.name + '_zkou\u0161ka_na\u010dten\xed', 'Czech'),
+            ('\uff3f\u30a4\u30f3\u30dd\u30fc\u30c8\u30c6\u30b9\u30c8',
+             'Japanese'),
+            ]
+        for name, lang in cases:
+            with self.subTest(name):
+                module = self.load_module_by_name(name)
+                self.assertEqual(module.__name__, name)
+                self.assertEqual(module.__doc__, "Module named in %s" % lang)
+
+    @unittest.skipIf(not hasattr(sys, 'gettotalrefcount'),
+            '--with-pydebug has to be enabled for this test')
+    def test_bad_traverse(self):
+        ''' Issue #32374: Test that traverse fails when accessing per-module
+            state before Py_mod_exec was executed.
+            (Multiphase initialization modules only)
+        '''
+        script = """if True:
+                try:
+                    from test import support
+                    import importlib.util as util
+                    spec = util.find_spec('_testmultiphase')
+                    spec.name = '_testmultiphase_with_bad_traverse'
+
+                    with support.SuppressCrashReport():
+                        m = spec.loader.create_module(spec)
+                except:
+                    # Prevent Python-level exceptions from
+                    # ending the process with non-zero status
+                    # (We are testing for a crash in C-code)
+                    pass"""
+        assert_python_failure("-c", script)
+
+
+(Frozen_MultiPhaseExtensionModuleTests,
+ Source_MultiPhaseExtensionModuleTests
+ ) = util.test_both(MultiPhaseExtensionModuleTests, machinery=machinery)
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/extension/test_path_hook.py

@@ -0,0 +1,31 @@
+from .. import util
+
+machinery = util.import_importlib('importlib.machinery')
+
+import unittest
+
+
+class PathHookTests:
+
+    """Test the path hook for extension modules."""
+    # XXX Should it only succeed for pre-existing directories?
+    # XXX Should it only work for directories containing an extension module?
+
+    def hook(self, entry):
+        return self.machinery.FileFinder.path_hook(
+                (self.machinery.ExtensionFileLoader,
+                 self.machinery.EXTENSION_SUFFIXES))(entry)
+
+    def test_success(self):
+        # Path hook should handle a directory where a known extension module
+        # exists.
+        self.assertTrue(hasattr(self.hook(util.EXTENSIONS.path), 'find_module'))
+
+
+(Frozen_PathHooksTests,
+ Source_PathHooksTests
+ ) = util.test_both(PathHookTests, machinery=machinery)
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/frozen/__init__.py

@@ -0,0 +1,5 @@
+import os
+from test.support import load_package_tests
+
+def load_tests(*args):
+    return load_package_tests(os.path.dirname(__file__), *args)

third_party/python/Lib/test/test_importlib/frozen/__main__.py

@@ -0,0 +1,4 @@
+from . import load_tests
+import unittest
+
+unittest.main()

third_party/python/Lib/test/test_importlib/frozen/test_finder.py

@@ -0,0 +1,84 @@
+from .. import abc
+from .. import util
+
+machinery = util.import_importlib('importlib.machinery')
+
+import unittest
+
+
+class FindSpecTests(abc.FinderTests):
+
+    """Test finding frozen modules."""
+
+    def find(self, name, path=None):
+        finder = self.machinery.FrozenImporter
+        return finder.find_spec(name, path)
+
+    def test_module(self):
+        name = '__hello__'
+        spec = self.find(name)
+        self.assertEqual(spec.origin, 'frozen')
+
+    def test_package(self):
+        spec = self.find('__phello__')
+        self.assertIsNotNone(spec)
+
+    def test_module_in_package(self):
+        spec = self.find('__phello__.spam', ['__phello__'])
+        self.assertIsNotNone(spec)
+
+    # No frozen package within another package to test with.
+    test_package_in_package = None
+
+    # No easy way to test.
+    test_package_over_module = None
+
+    def test_failure(self):
+        spec = self.find('<not real>')
+        self.assertIsNone(spec)
+
+
+(Frozen_FindSpecTests,
+ Source_FindSpecTests
+ ) = util.test_both(FindSpecTests, machinery=machinery)
+
+
+class FinderTests(abc.FinderTests):
+
+    """Test finding frozen modules."""
+
+    def find(self, name, path=None):
+        finder = self.machinery.FrozenImporter
+        return finder.find_module(name, path)
+
+    def test_module(self):
+        name = '__hello__'
+        loader = self.find(name)
+        self.assertTrue(hasattr(loader, 'load_module'))
+
+    def test_package(self):
+        loader = self.find('__phello__')
+        self.assertTrue(hasattr(loader, 'load_module'))
+
+    def test_module_in_package(self):
+        loader = self.find('__phello__.spam', ['__phello__'])
+        self.assertTrue(hasattr(loader, 'load_module'))
+
+    # No frozen package within another package to test with.
+    test_package_in_package = None
+
+    # No easy way to test.
+    test_package_over_module = None
+
+    def test_failure(self):
+        loader = self.find('<not real>')
+        self.assertIsNone(loader)
+
+
+(Frozen_FinderTests,
+ Source_FinderTests
+ ) = util.test_both(FinderTests, machinery=machinery)
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/frozen/test_loader.py

@@ -0,0 +1,225 @@
+from .. import abc
+from .. import util
+
+machinery = util.import_importlib('importlib.machinery')
+
+from test.support import captured_stdout
+import types
+import unittest
+import warnings
+
+
+class ExecModuleTests(abc.LoaderTests):
+
+    def exec_module(self, name):
+        with util.uncache(name), captured_stdout() as stdout:
+            spec = self.machinery.ModuleSpec(
+                    name, self.machinery.FrozenImporter, origin='frozen',
+                    is_package=self.machinery.FrozenImporter.is_package(name))
+            module = types.ModuleType(name)
+            module.__spec__ = spec
+            assert not hasattr(module, 'initialized')
+            self.machinery.FrozenImporter.exec_module(module)
+            self.assertTrue(module.initialized)
+            self.assertTrue(hasattr(module, '__spec__'))
+            self.assertEqual(module.__spec__.origin, 'frozen')
+            return module, stdout.getvalue()
+
+    def test_module(self):
+        name = '__hello__'
+        module, output = self.exec_module(name)
+        check = {'__name__': name}
+        for attr, value in check.items():
+            self.assertEqual(getattr(module, attr), value)
+        self.assertEqual(output, 'Hello world!\n')
+        self.assertTrue(hasattr(module, '__spec__'))
+
+    def test_package(self):
+        name = '__phello__'
+        module, output = self.exec_module(name)
+        check = {'__name__': name}
+        for attr, value in check.items():
+            attr_value = getattr(module, attr)
+            self.assertEqual(attr_value, value,
+                        'for {name}.{attr}, {given!r} != {expected!r}'.format(
+                                 name=name, attr=attr, given=attr_value,
+                                 expected=value))
+        self.assertEqual(output, 'Hello world!\n')
+
+    def test_lacking_parent(self):
+        name = '__phello__.spam'
+        with util.uncache('__phello__'):
+            module, output = self.exec_module(name)
+            check = {'__name__': name}
+            for attr, value in check.items():
+                attr_value = getattr(module, attr)
+                self.assertEqual(attr_value, value,
+                        'for {name}.{attr}, {given} != {expected!r}'.format(
+                                 name=name, attr=attr, given=attr_value,
+                                 expected=value))
+            self.assertEqual(output, 'Hello world!\n')
+
+    def test_module_repr(self):
+        name = '__hello__'
+        module, output = self.exec_module(name)
+        with warnings.catch_warnings():
+            warnings.simplefilter('ignore', DeprecationWarning)
+            repr_str = self.machinery.FrozenImporter.module_repr(module)
+        self.assertEqual(repr_str,
+                         "<module '__hello__' (frozen)>")
+
+    def test_module_repr_indirect(self):
+        name = '__hello__'
+        module, output = self.exec_module(name)
+        self.assertEqual(repr(module),
+                         "<module '__hello__' (frozen)>")
+
+    # No way to trigger an error in a frozen module.
+    test_state_after_failure = None
+
+    def test_unloadable(self):
+        assert self.machinery.FrozenImporter.find_module('_not_real') is None
+        with self.assertRaises(ImportError) as cm:
+            self.exec_module('_not_real')
+        self.assertEqual(cm.exception.name, '_not_real')
+
+
+(Frozen_ExecModuleTests,
+ Source_ExecModuleTests
+ ) = util.test_both(ExecModuleTests, machinery=machinery)
+
+
+class LoaderTests(abc.LoaderTests):
+
+    def test_module(self):
+        with util.uncache('__hello__'), captured_stdout() as stdout:
+            with warnings.catch_warnings():
+                warnings.simplefilter('ignore', DeprecationWarning)
+                module = self.machinery.FrozenImporter.load_module('__hello__')
+            check = {'__name__': '__hello__',
+                    '__package__': '',
+                    '__loader__': self.machinery.FrozenImporter,
+                    }
+            for attr, value in check.items():
+                self.assertEqual(getattr(module, attr), value)
+            self.assertEqual(stdout.getvalue(), 'Hello world!\n')
+            self.assertFalse(hasattr(module, '__file__'))
+
+    def test_package(self):
+        with util.uncache('__phello__'),  captured_stdout() as stdout:
+            with warnings.catch_warnings():
+                warnings.simplefilter('ignore', DeprecationWarning)
+                module = self.machinery.FrozenImporter.load_module('__phello__')
+            check = {'__name__': '__phello__',
+                     '__package__': '__phello__',
+                     '__path__': [],
+                     '__loader__': self.machinery.FrozenImporter,
+                     }
+            for attr, value in check.items():
+                attr_value = getattr(module, attr)
+                self.assertEqual(attr_value, value,
+                                 "for __phello__.%s, %r != %r" %
+                                 (attr, attr_value, value))
+            self.assertEqual(stdout.getvalue(), 'Hello world!\n')
+            self.assertFalse(hasattr(module, '__file__'))
+
+    def test_lacking_parent(self):
+        with util.uncache('__phello__', '__phello__.spam'), \
+             captured_stdout() as stdout:
+            with warnings.catch_warnings():
+                warnings.simplefilter('ignore', DeprecationWarning)
+                module = self.machinery.FrozenImporter.load_module('__phello__.spam')
+            check = {'__name__': '__phello__.spam',
+                    '__package__': '__phello__',
+                    '__loader__': self.machinery.FrozenImporter,
+                    }
+            for attr, value in check.items():
+                attr_value = getattr(module, attr)
+                self.assertEqual(attr_value, value,
+                                 "for __phello__.spam.%s, %r != %r" %
+                                 (attr, attr_value, value))
+            self.assertEqual(stdout.getvalue(), 'Hello world!\n')
+            self.assertFalse(hasattr(module, '__file__'))
+
+    def test_module_reuse(self):
+        with util.uncache('__hello__'), captured_stdout() as stdout:
+            with warnings.catch_warnings():
+                warnings.simplefilter('ignore', DeprecationWarning)
+                module1 = self.machinery.FrozenImporter.load_module('__hello__')
+                module2 = self.machinery.FrozenImporter.load_module('__hello__')
+            self.assertIs(module1, module2)
+            self.assertEqual(stdout.getvalue(),
+                             'Hello world!\nHello world!\n')
+
+    def test_module_repr(self):
+        with util.uncache('__hello__'), captured_stdout():
+            with warnings.catch_warnings():
+                warnings.simplefilter('ignore', DeprecationWarning)
+                module = self.machinery.FrozenImporter.load_module('__hello__')
+                repr_str = self.machinery.FrozenImporter.module_repr(module)
+            self.assertEqual(repr_str,
+                             "<module '__hello__' (frozen)>")
+
+    def test_module_repr_indirect(self):
+        with util.uncache('__hello__'), captured_stdout():
+            module = self.machinery.FrozenImporter.load_module('__hello__')
+        self.assertEqual(repr(module),
+                         "<module '__hello__' (frozen)>")
+
+    # No way to trigger an error in a frozen module.
+    test_state_after_failure = None
+
+    def test_unloadable(self):
+        assert self.machinery.FrozenImporter.find_module('_not_real') is None
+        with self.assertRaises(ImportError) as cm:
+            self.machinery.FrozenImporter.load_module('_not_real')
+        self.assertEqual(cm.exception.name, '_not_real')
+
+
+(Frozen_LoaderTests,
+ Source_LoaderTests
+ ) = util.test_both(LoaderTests, machinery=machinery)
+
+
+class InspectLoaderTests:
+
+    """Tests for the InspectLoader methods for FrozenImporter."""
+
+    def test_get_code(self):
+        # Make sure that the code object is good.
+        name = '__hello__'
+        with captured_stdout() as stdout:
+            code = self.machinery.FrozenImporter.get_code(name)
+            mod = types.ModuleType(name)
+            exec(code, mod.__dict__)
+            self.assertTrue(hasattr(mod, 'initialized'))
+            self.assertEqual(stdout.getvalue(), 'Hello world!\n')
+
+    def test_get_source(self):
+        # Should always return None.
+        result = self.machinery.FrozenImporter.get_source('__hello__')
+        self.assertIsNone(result)
+
+    def test_is_package(self):
+        # Should be able to tell what is a package.
+        test_for = (('__hello__', False), ('__phello__', True),
+                    ('__phello__.spam', False))
+        for name, is_package in test_for:
+            result = self.machinery.FrozenImporter.is_package(name)
+            self.assertEqual(bool(result), is_package)
+
+    def test_failure(self):
+        # Raise ImportError for modules that are not frozen.
+        for meth_name in ('get_code', 'get_source', 'is_package'):
+            method = getattr(self.machinery.FrozenImporter, meth_name)
+            with self.assertRaises(ImportError) as cm:
+                method('importlib')
+            self.assertEqual(cm.exception.name, 'importlib')
+
+(Frozen_ILTests,
+ Source_ILTests
+ ) = util.test_both(InspectLoaderTests, machinery=machinery)
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/import_/__init__.py

@@ -0,0 +1,5 @@
+import os
+from test.support import load_package_tests
+
+def load_tests(*args):
+    return load_package_tests(os.path.dirname(__file__), *args)

third_party/python/Lib/test/test_importlib/import_/__main__.py

@@ -0,0 +1,4 @@
+from . import load_tests
+import unittest
+
+unittest.main()

third_party/python/Lib/test/test_importlib/import_/test___loader__.py

@@ -0,0 +1,75 @@
+from importlib import machinery
+import sys
+import types
+import unittest
+
+from .. import util
+
+
+class SpecLoaderMock:
+
+    def find_spec(self, fullname, path=None, target=None):
+        return machinery.ModuleSpec(fullname, self)
+
+    def create_module(self, spec):
+        return None
+
+    def exec_module(self, module):
+        pass
+
+
+class SpecLoaderAttributeTests:
+
+    def test___loader__(self):
+        loader = SpecLoaderMock()
+        with util.uncache('blah'), util.import_state(meta_path=[loader]):
+            module = self.__import__('blah')
+        self.assertEqual(loader, module.__loader__)
+
+
+(Frozen_SpecTests,
+ Source_SpecTests
+ ) = util.test_both(SpecLoaderAttributeTests, __import__=util.__import__)
+
+
+class LoaderMock:
+
+    def find_module(self, fullname, path=None):
+        return self
+
+    def load_module(self, fullname):
+        sys.modules[fullname] = self.module
+        return self.module
+
+
+class LoaderAttributeTests:
+
+    def test___loader___missing(self):
+        module = types.ModuleType('blah')
+        try:
+            del module.__loader__
+        except AttributeError:
+            pass
+        loader = LoaderMock()
+        loader.module = module
+        with util.uncache('blah'), util.import_state(meta_path=[loader]):
+            module = self.__import__('blah')
+        self.assertEqual(loader, module.__loader__)
+
+    def test___loader___is_None(self):
+        module = types.ModuleType('blah')
+        module.__loader__ = None
+        loader = LoaderMock()
+        loader.module = module
+        with util.uncache('blah'), util.import_state(meta_path=[loader]):
+            returned_module = self.__import__('blah')
+        self.assertEqual(loader, module.__loader__)
+
+
+(Frozen_Tests,
+ Source_Tests
+ ) = util.test_both(LoaderAttributeTests, __import__=util.__import__)
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/import_/test___package__.py

@@ -0,0 +1,163 @@
+"""PEP 366 ("Main module explicit relative imports") specifies the
+semantics for the __package__ attribute on modules. This attribute is
+used, when available, to detect which package a module belongs to (instead
+of using the typical __path__/__name__ test).
+
+"""
+import unittest
+import warnings
+from .. import util
+
+
+class Using__package__:
+
+    """Use of __package__ supercedes the use of __name__/__path__ to calculate
+    what package a module belongs to. The basic algorithm is [__package__]::
+
+      def resolve_name(name, package, level):
+          level -= 1
+          base = package.rsplit('.', level)[0]
+          return '{0}.{1}'.format(base, name)
+
+    But since there is no guarantee that __package__ has been set (or not been
+    set to None [None]), there has to be a way to calculate the attribute's value
+    [__name__]::
+
+      def calc_package(caller_name, has___path__):
+          if has__path__:
+              return caller_name
+          else:
+              return caller_name.rsplit('.', 1)[0]
+
+    Then the normal algorithm for relative name imports can proceed as if
+    __package__ had been set.
+
+    """
+
+    def import_module(self, globals_):
+        with self.mock_modules('pkg.__init__', 'pkg.fake') as importer:
+            with util.import_state(meta_path=[importer]):
+                self.__import__('pkg.fake')
+                module = self.__import__('',
+                                         globals=globals_,
+                                         fromlist=['attr'], level=2)
+        return module
+
+    def test_using___package__(self):
+        # [__package__]
+        module = self.import_module({'__package__': 'pkg.fake'})
+        self.assertEqual(module.__name__, 'pkg')
+
+    def test_using___name__(self):
+        # [__name__]
+        with warnings.catch_warnings():
+            warnings.simplefilter("ignore")
+            module = self.import_module({'__name__': 'pkg.fake',
+                                         '__path__': []})
+        self.assertEqual(module.__name__, 'pkg')
+
+    def test_warn_when_using___name__(self):
+        with self.assertWarns(ImportWarning):
+            self.import_module({'__name__': 'pkg.fake', '__path__': []})
+
+    def test_None_as___package__(self):
+        # [None]
+        with warnings.catch_warnings():
+            warnings.simplefilter("ignore")
+            module = self.import_module({
+                '__name__': 'pkg.fake', '__path__': [], '__package__': None })
+        self.assertEqual(module.__name__, 'pkg')
+
+    def test_spec_fallback(self):
+        # If __package__ isn't defined, fall back on __spec__.parent.
+        module = self.import_module({'__spec__': FakeSpec('pkg.fake')})
+        self.assertEqual(module.__name__, 'pkg')
+
+    def test_warn_when_package_and_spec_disagree(self):
+        # Raise an ImportWarning if __package__ != __spec__.parent.
+        with self.assertWarns(ImportWarning):
+            self.import_module({'__package__': 'pkg.fake',
+                                '__spec__': FakeSpec('pkg.fakefake')})
+
+    def test_bad__package__(self):
+        globals = {'__package__': '<not real>'}
+        with self.assertRaises(ModuleNotFoundError):
+            self.__import__('', globals, {}, ['relimport'], 1)
+
+    def test_bunk__package__(self):
+        globals = {'__package__': 42}
+        with self.assertRaises(TypeError):
+            self.__import__('', globals, {}, ['relimport'], 1)
+
+
+class FakeSpec:
+    def __init__(self, parent):
+        self.parent = parent
+
+
+class Using__package__PEP302(Using__package__):
+    mock_modules = util.mock_modules
+
+
+(Frozen_UsingPackagePEP302,
+ Source_UsingPackagePEP302
+ ) = util.test_both(Using__package__PEP302, __import__=util.__import__)
+
+
+class Using__package__PEP451(Using__package__):
+    mock_modules = util.mock_spec
+
+
+(Frozen_UsingPackagePEP451,
+ Source_UsingPackagePEP451
+ ) = util.test_both(Using__package__PEP451, __import__=util.__import__)
+
+
+class Setting__package__:
+
+    """Because __package__ is a new feature, it is not always set by a loader.
+    Import will set it as needed to help with the transition to relying on
+    __package__.
+
+    For a top-level module, __package__ is set to None [top-level]. For a
+    package __name__ is used for __package__ [package]. For submodules the
+    value is __name__.rsplit('.', 1)[0] [submodule].
+
+    """
+
+    __import__ = util.__import__['Source']
+
+    # [top-level]
+    def test_top_level(self):
+        with self.mock_modules('top_level') as mock:
+            with util.import_state(meta_path=[mock]):
+                del mock['top_level'].__package__
+                module = self.__import__('top_level')
+                self.assertEqual(module.__package__, '')
+
+    # [package]
+    def test_package(self):
+        with self.mock_modules('pkg.__init__') as mock:
+            with util.import_state(meta_path=[mock]):
+                del mock['pkg'].__package__
+                module = self.__import__('pkg')
+                self.assertEqual(module.__package__, 'pkg')
+
+    # [submodule]
+    def test_submodule(self):
+        with self.mock_modules('pkg.__init__', 'pkg.mod') as mock:
+            with util.import_state(meta_path=[mock]):
+                del mock['pkg.mod'].__package__
+                pkg = self.__import__('pkg.mod')
+                module = getattr(pkg, 'mod')
+                self.assertEqual(module.__package__, 'pkg')
+
+class Setting__package__PEP302(Setting__package__, unittest.TestCase):
+    mock_modules = util.mock_modules
+
+class Setting__package__PEP451(Setting__package__, unittest.TestCase):
+    mock_modules = util.mock_spec
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/import_/test_api.py

@@ -0,0 +1,119 @@
+from .. import util
+
+from importlib import machinery
+import sys
+import types
+import unittest
+
+PKG_NAME = 'fine'
+SUBMOD_NAME = 'fine.bogus'
+
+
+class BadSpecFinderLoader:
+    @classmethod
+    def find_spec(cls, fullname, path=None, target=None):
+        if fullname == SUBMOD_NAME:
+            spec = machinery.ModuleSpec(fullname, cls)
+            return spec
+
+    @staticmethod
+    def create_module(spec):
+        return None
+
+    @staticmethod
+    def exec_module(module):
+        if module.__name__ == SUBMOD_NAME:
+            raise ImportError('I cannot be loaded!')
+
+
+class BadLoaderFinder:
+    @classmethod
+    def find_module(cls, fullname, path):
+        if fullname == SUBMOD_NAME:
+            return cls
+
+    @classmethod
+    def load_module(cls, fullname):
+        if fullname == SUBMOD_NAME:
+            raise ImportError('I cannot be loaded!')
+
+
+class APITest:
+
+    """Test API-specific details for __import__ (e.g. raising the right
+    exception when passing in an int for the module name)."""
+
+    def test_raises_ModuleNotFoundError(self):
+        with self.assertRaises(ModuleNotFoundError):
+            util.import_importlib('some module that does not exist')
+
+    def test_name_requires_rparition(self):
+        # Raise TypeError if a non-string is passed in for the module name.
+        with self.assertRaises(TypeError):
+            self.__import__(42)
+
+    def test_negative_level(self):
+        # Raise ValueError when a negative level is specified.
+        # PEP 328 did away with sys.module None entries and the ambiguity of
+        # absolute/relative imports.
+        with self.assertRaises(ValueError):
+            self.__import__('os', globals(), level=-1)
+
+    def test_nonexistent_fromlist_entry(self):
+        # If something in fromlist doesn't exist, that's okay.
+        # issue15715
+        mod = types.ModuleType(PKG_NAME)
+        mod.__path__ = ['XXX']
+        with util.import_state(meta_path=[self.bad_finder_loader]):
+            with util.uncache(PKG_NAME):
+                sys.modules[PKG_NAME] = mod
+                self.__import__(PKG_NAME, fromlist=['not here'])
+
+    def test_fromlist_load_error_propagates(self):
+        # If something in fromlist triggers an exception not related to not
+        # existing, let that exception propagate.
+        # issue15316
+        mod = types.ModuleType(PKG_NAME)
+        mod.__path__ = ['XXX']
+        with util.import_state(meta_path=[self.bad_finder_loader]):
+            with util.uncache(PKG_NAME):
+                sys.modules[PKG_NAME] = mod
+                with self.assertRaises(ImportError):
+                    self.__import__(PKG_NAME,
+                                    fromlist=[SUBMOD_NAME.rpartition('.')[-1]])
+
+    def test_blocked_fromlist(self):
+        # If fromlist entry is None, let a ModuleNotFoundError propagate.
+        # issue31642
+        mod = types.ModuleType(PKG_NAME)
+        mod.__path__ = []
+        with util.import_state(meta_path=[self.bad_finder_loader]):
+            with util.uncache(PKG_NAME, SUBMOD_NAME):
+                sys.modules[PKG_NAME] = mod
+                sys.modules[SUBMOD_NAME] = None
+                with self.assertRaises(ModuleNotFoundError) as cm:
+                    self.__import__(PKG_NAME,
+                                    fromlist=[SUBMOD_NAME.rpartition('.')[-1]])
+                self.assertEqual(cm.exception.name, SUBMOD_NAME)
+
+
+class OldAPITests(APITest):
+    bad_finder_loader = BadLoaderFinder
+
+
+(Frozen_OldAPITests,
+ Source_OldAPITests
+ ) = util.test_both(OldAPITests, __import__=util.__import__)
+
+
+class SpecAPITests(APITest):
+    bad_finder_loader = BadSpecFinderLoader
+
+
+(Frozen_SpecAPITests,
+ Source_SpecAPITests
+ ) = util.test_both(SpecAPITests, __import__=util.__import__)
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/import_/test_caching.py

@@ -0,0 +1,93 @@
+"""Test that sys.modules is used properly by import."""
+from .. import util
+import sys
+from types import MethodType
+import unittest
+
+
+class UseCache:
+
+    """When it comes to sys.modules, import prefers it over anything else.
+
+    Once a name has been resolved, sys.modules is checked to see if it contains
+    the module desired. If so, then it is returned [use cache]. If it is not
+    found, then the proper steps are taken to perform the import, but
+    sys.modules is still used to return the imported module (e.g., not what a
+    loader returns) [from cache on return]. This also applies to imports of
+    things contained within a package and thus get assigned as an attribute
+    [from cache to attribute] or pulled in thanks to a fromlist import
+    [from cache for fromlist]. But if sys.modules contains None then
+    ImportError is raised [None in cache].
+
+    """
+
+    def test_using_cache(self):
+        # [use cache]
+        module_to_use = "some module found!"
+        with util.uncache('some_module'):
+            sys.modules['some_module'] = module_to_use
+            module = self.__import__('some_module')
+            self.assertEqual(id(module_to_use), id(module))
+
+    def test_None_in_cache(self):
+        #[None in cache]
+        name = 'using_None'
+        with util.uncache(name):
+            sys.modules[name] = None
+            with self.assertRaises(ImportError) as cm:
+                self.__import__(name)
+            self.assertEqual(cm.exception.name, name)
+
+
+(Frozen_UseCache,
+ Source_UseCache
+ ) = util.test_both(UseCache, __import__=util.__import__)
+
+
+class ImportlibUseCache(UseCache, unittest.TestCase):
+
+    # Pertinent only to PEP 302; exec_module() doesn't return a module.
+
+    __import__ = util.__import__['Source']
+
+    def create_mock(self, *names, return_=None):
+        mock = util.mock_modules(*names)
+        original_load = mock.load_module
+        def load_module(self, fullname):
+            original_load(fullname)
+            return return_
+        mock.load_module = MethodType(load_module, mock)
+        return mock
+
+    # __import__ inconsistent between loaders and built-in import when it comes
+    #   to when to use the module in sys.modules and when not to.
+    def test_using_cache_after_loader(self):
+        # [from cache on return]
+        with self.create_mock('module') as mock:
+            with util.import_state(meta_path=[mock]):
+                module = self.__import__('module')
+                self.assertEqual(id(module), id(sys.modules['module']))
+
+    # See test_using_cache_after_loader() for reasoning.
+    def test_using_cache_for_assigning_to_attribute(self):
+        # [from cache to attribute]
+        with self.create_mock('pkg.__init__', 'pkg.module') as importer:
+            with util.import_state(meta_path=[importer]):
+                module = self.__import__('pkg.module')
+                self.assertTrue(hasattr(module, 'module'))
+                self.assertEqual(id(module.module),
+                                 id(sys.modules['pkg.module']))
+
+    # See test_using_cache_after_loader() for reasoning.
+    def test_using_cache_for_fromlist(self):
+        # [from cache for fromlist]
+        with self.create_mock('pkg.__init__', 'pkg.module') as importer:
+            with util.import_state(meta_path=[importer]):
+                module = self.__import__('pkg', fromlist=['module'])
+                self.assertTrue(hasattr(module, 'module'))
+                self.assertEqual(id(module.module),
+                                 id(sys.modules['pkg.module']))
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/import_/test_fromlist.py

@@ -0,0 +1,175 @@
+"""Test that the semantics relating to the 'fromlist' argument are correct."""
+from .. import util
+import warnings
+import unittest
+
+
+class ReturnValue:
+
+    """The use of fromlist influences what import returns.
+
+    If direct ``import ...`` statement is used, the root module or package is
+    returned [import return]. But if fromlist is set, then the specified module
+    is actually returned (whether it is a relative import or not)
+    [from return].
+
+    """
+
+    def test_return_from_import(self):
+        # [import return]
+        with util.mock_spec('pkg.__init__', 'pkg.module') as importer:
+            with util.import_state(meta_path=[importer]):
+                module = self.__import__('pkg.module')
+                self.assertEqual(module.__name__, 'pkg')
+
+    def test_return_from_from_import(self):
+        # [from return]
+        with util.mock_modules('pkg.__init__', 'pkg.module')as importer:
+            with util.import_state(meta_path=[importer]):
+                module = self.__import__('pkg.module', fromlist=['attr'])
+                self.assertEqual(module.__name__, 'pkg.module')
+
+
+(Frozen_ReturnValue,
+ Source_ReturnValue
+ ) = util.test_both(ReturnValue, __import__=util.__import__)
+
+
+class HandlingFromlist:
+
+    """Using fromlist triggers different actions based on what is being asked
+    of it.
+
+    If fromlist specifies an object on a module, nothing special happens
+    [object case]. This is even true if the object does not exist [bad object].
+
+    If a package is being imported, then what is listed in fromlist may be
+    treated as a module to be imported [module]. And this extends to what is
+    contained in __all__ when '*' is imported [using *]. And '*' does not need
+    to be the only name in the fromlist [using * with others].
+
+    """
+
+    def test_object(self):
+        # [object case]
+        with util.mock_modules('module') as importer:
+            with util.import_state(meta_path=[importer]):
+                module = self.__import__('module', fromlist=['attr'])
+                self.assertEqual(module.__name__, 'module')
+
+    def test_nonexistent_object(self):
+        # [bad object]
+        with util.mock_modules('module') as importer:
+            with util.import_state(meta_path=[importer]):
+                module = self.__import__('module', fromlist=['non_existent'])
+                self.assertEqual(module.__name__, 'module')
+                self.assertFalse(hasattr(module, 'non_existent'))
+
+    def test_module_from_package(self):
+        # [module]
+        with util.mock_modules('pkg.__init__', 'pkg.module') as importer:
+            with util.import_state(meta_path=[importer]):
+                module = self.__import__('pkg', fromlist=['module'])
+                self.assertEqual(module.__name__, 'pkg')
+                self.assertTrue(hasattr(module, 'module'))
+                self.assertEqual(module.module.__name__, 'pkg.module')
+
+    def test_nonexistent_from_package(self):
+        with util.mock_modules('pkg.__init__') as importer:
+            with util.import_state(meta_path=[importer]):
+                module = self.__import__('pkg', fromlist=['non_existent'])
+                self.assertEqual(module.__name__, 'pkg')
+                self.assertFalse(hasattr(module, 'non_existent'))
+
+    def test_module_from_package_triggers_ModuleNotFoundError(self):
+        # If a submodule causes an ModuleNotFoundError because it tries
+        # to import a module which doesn't exist, that should let the
+        # ModuleNotFoundError propagate.
+        def module_code():
+            import i_do_not_exist
+        with util.mock_modules('pkg.__init__', 'pkg.mod',
+                               module_code={'pkg.mod': module_code}) as importer:
+            with util.import_state(meta_path=[importer]):
+                with self.assertRaises(ModuleNotFoundError) as exc:
+                    self.__import__('pkg', fromlist=['mod'])
+                self.assertEqual('i_do_not_exist', exc.exception.name)
+
+    def test_empty_string(self):
+        with util.mock_modules('pkg.__init__', 'pkg.mod') as importer:
+            with util.import_state(meta_path=[importer]):
+                module = self.__import__('pkg.mod', fromlist=[''])
+                self.assertEqual(module.__name__, 'pkg.mod')
+
+    def basic_star_test(self, fromlist=['*']):
+        # [using *]
+        with util.mock_modules('pkg.__init__', 'pkg.module') as mock:
+            with util.import_state(meta_path=[mock]):
+                mock['pkg'].__all__ = ['module']
+                module = self.__import__('pkg', fromlist=fromlist)
+                self.assertEqual(module.__name__, 'pkg')
+                self.assertTrue(hasattr(module, 'module'))
+                self.assertEqual(module.module.__name__, 'pkg.module')
+
+    def test_using_star(self):
+        # [using *]
+        self.basic_star_test()
+
+    def test_fromlist_as_tuple(self):
+        self.basic_star_test(('*',))
+
+    def test_star_with_others(self):
+        # [using * with others]
+        context = util.mock_modules('pkg.__init__', 'pkg.module1', 'pkg.module2')
+        with context as mock:
+            with util.import_state(meta_path=[mock]):
+                mock['pkg'].__all__ = ['module1']
+                module = self.__import__('pkg', fromlist=['module2', '*'])
+                self.assertEqual(module.__name__, 'pkg')
+                self.assertTrue(hasattr(module, 'module1'))
+                self.assertTrue(hasattr(module, 'module2'))
+                self.assertEqual(module.module1.__name__, 'pkg.module1')
+                self.assertEqual(module.module2.__name__, 'pkg.module2')
+
+    def test_nonexistent_in_all(self):
+        with util.mock_modules('pkg.__init__') as importer:
+            with util.import_state(meta_path=[importer]):
+                importer['pkg'].__all__ = ['non_existent']
+                module = self.__import__('pkg', fromlist=['*'])
+                self.assertEqual(module.__name__, 'pkg')
+                self.assertFalse(hasattr(module, 'non_existent'))
+
+    def test_star_in_all(self):
+        with util.mock_modules('pkg.__init__') as importer:
+            with util.import_state(meta_path=[importer]):
+                importer['pkg'].__all__ = ['*']
+                module = self.__import__('pkg', fromlist=['*'])
+                self.assertEqual(module.__name__, 'pkg')
+                self.assertFalse(hasattr(module, '*'))
+
+    def test_invalid_type(self):
+        with util.mock_modules('pkg.__init__') as importer:
+            with util.import_state(meta_path=[importer]), \
+                 warnings.catch_warnings():
+                warnings.simplefilter('error', BytesWarning)
+                with self.assertRaisesRegex(TypeError, r'\bfrom\b'):
+                    self.__import__('pkg', fromlist=[b'attr'])
+                with self.assertRaisesRegex(TypeError, r'\bfrom\b'):
+                    self.__import__('pkg', fromlist=iter([b'attr']))
+
+    def test_invalid_type_in_all(self):
+        with util.mock_modules('pkg.__init__') as importer:
+            with util.import_state(meta_path=[importer]), \
+                 warnings.catch_warnings():
+                warnings.simplefilter('error', BytesWarning)
+                importer['pkg'].__all__ = [b'attr']
+                with self.assertRaisesRegex(TypeError, r'\bpkg\.__all__\b'):
+                    self.__import__('pkg', fromlist=['*'])
+
+
+(Frozen_FromList,
+ Source_FromList
+ ) = util.test_both(HandlingFromlist, __import__=util.__import__)
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/import_/test_meta_path.py

@@ -0,0 +1,125 @@
+from .. import util
+import importlib._bootstrap
+import sys
+from types import MethodType
+import unittest
+import warnings
+
+
+class CallingOrder:
+
+    """Calls to the importers on sys.meta_path happen in order that they are
+    specified in the sequence, starting with the first importer
+    [first called], and then continuing on down until one is found that doesn't
+    return None [continuing]."""
+
+
+    def test_first_called(self):
+        # [first called]
+        mod = 'top_level'
+        with util.mock_spec(mod) as first, util.mock_spec(mod) as second:
+            with util.import_state(meta_path=[first, second]):
+                self.assertIs(self.__import__(mod), first.modules[mod])
+
+    def test_continuing(self):
+        # [continuing]
+        mod_name = 'for_real'
+        with util.mock_spec('nonexistent') as first, \
+             util.mock_spec(mod_name) as second:
+            first.find_spec = lambda self, fullname, path=None, parent=None: None
+            with util.import_state(meta_path=[first, second]):
+                self.assertIs(self.__import__(mod_name), second.modules[mod_name])
+
+    def test_empty(self):
+        # Raise an ImportWarning if sys.meta_path is empty.
+        module_name = 'nothing'
+        try:
+            del sys.modules[module_name]
+        except KeyError:
+            pass
+        with util.import_state(meta_path=[]):
+            with warnings.catch_warnings(record=True) as w:
+                warnings.simplefilter('always')
+                self.assertIsNone(importlib._bootstrap._find_spec('nothing',
+                                                                  None))
+                self.assertEqual(len(w), 1)
+                self.assertTrue(issubclass(w[-1].category, ImportWarning))
+
+
+(Frozen_CallingOrder,
+ Source_CallingOrder
+ ) = util.test_both(CallingOrder, __import__=util.__import__)
+
+
+class CallSignature:
+
+    """If there is no __path__ entry on the parent module, then 'path' is None
+    [no path]. Otherwise, the value for __path__ is passed in for the 'path'
+    argument [path set]."""
+
+    def log_finder(self, importer):
+        fxn = getattr(importer, self.finder_name)
+        log = []
+        def wrapper(self, *args, **kwargs):
+            log.append([args, kwargs])
+            return fxn(*args, **kwargs)
+        return log, wrapper
+
+    def test_no_path(self):
+        # [no path]
+        mod_name = 'top_level'
+        assert '.' not in mod_name
+        with self.mock_modules(mod_name) as importer:
+            log, wrapped_call = self.log_finder(importer)
+            setattr(importer, self.finder_name, MethodType(wrapped_call, importer))
+            with util.import_state(meta_path=[importer]):
+                self.__import__(mod_name)
+                assert len(log) == 1
+                args = log[0][0]
+                # Assuming all arguments are positional.
+                self.assertEqual(args[0], mod_name)
+                self.assertIsNone(args[1])
+
+    def test_with_path(self):
+        # [path set]
+        pkg_name = 'pkg'
+        mod_name = pkg_name + '.module'
+        path = [42]
+        assert '.' in mod_name
+        with self.mock_modules(pkg_name+'.__init__', mod_name) as importer:
+            importer.modules[pkg_name].__path__ = path
+            log, wrapped_call = self.log_finder(importer)
+            setattr(importer, self.finder_name, MethodType(wrapped_call, importer))
+            with util.import_state(meta_path=[importer]):
+                self.__import__(mod_name)
+                assert len(log) == 2
+                args = log[1][0]
+                kwargs = log[1][1]
+                # Assuming all arguments are positional.
+                self.assertFalse(kwargs)
+                self.assertEqual(args[0], mod_name)
+                self.assertIs(args[1], path)
+
+
+class CallSignaturePEP302(CallSignature):
+    mock_modules = util.mock_modules
+    finder_name = 'find_module'
+
+
+(Frozen_CallSignaturePEP302,
+ Source_CallSignaturePEP302
+ ) = util.test_both(CallSignaturePEP302, __import__=util.__import__)
+
+
+class CallSignaturePEP451(CallSignature):
+    mock_modules = util.mock_spec
+    finder_name = 'find_spec'
+
+
+(Frozen_CallSignaturePEP451,
+ Source_CallSignaturePEP451
+ ) = util.test_both(CallSignaturePEP451, __import__=util.__import__)
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/import_/test_packages.py

@@ -0,0 +1,110 @@
+from .. import util
+import sys
+import unittest
+from test import support
+
+
+class ParentModuleTests:
+
+    """Importing a submodule should import the parent modules."""
+
+    def test_import_parent(self):
+        with util.mock_spec('pkg.__init__', 'pkg.module') as mock:
+            with util.import_state(meta_path=[mock]):
+                module = self.__import__('pkg.module')
+                self.assertIn('pkg', sys.modules)
+
+    def test_bad_parent(self):
+        with util.mock_spec('pkg.module') as mock:
+            with util.import_state(meta_path=[mock]):
+                with self.assertRaises(ImportError) as cm:
+                    self.__import__('pkg.module')
+                self.assertEqual(cm.exception.name, 'pkg')
+
+    def test_raising_parent_after_importing_child(self):
+        def __init__():
+            import pkg.module
+            1/0
+        mock = util.mock_spec('pkg.__init__', 'pkg.module',
+                                 module_code={'pkg': __init__})
+        with mock:
+            with util.import_state(meta_path=[mock]):
+                with self.assertRaises(ZeroDivisionError):
+                    self.__import__('pkg')
+                self.assertNotIn('pkg', sys.modules)
+                self.assertIn('pkg.module', sys.modules)
+                with self.assertRaises(ZeroDivisionError):
+                    self.__import__('pkg.module')
+                self.assertNotIn('pkg', sys.modules)
+                self.assertIn('pkg.module', sys.modules)
+
+    def test_raising_parent_after_relative_importing_child(self):
+        def __init__():
+            from . import module
+            1/0
+        mock = util.mock_spec('pkg.__init__', 'pkg.module',
+                                 module_code={'pkg': __init__})
+        with mock:
+            with util.import_state(meta_path=[mock]):
+                with self.assertRaises((ZeroDivisionError, ImportError)):
+                    # This raises ImportError on the "from . import module"
+                    # line, not sure why.
+                    self.__import__('pkg')
+                self.assertNotIn('pkg', sys.modules)
+                with self.assertRaises((ZeroDivisionError, ImportError)):
+                    self.__import__('pkg.module')
+                self.assertNotIn('pkg', sys.modules)
+                # XXX False
+                #self.assertIn('pkg.module', sys.modules)
+
+    def test_raising_parent_after_double_relative_importing_child(self):
+        def __init__():
+            from ..subpkg import module
+            1/0
+        mock = util.mock_spec('pkg.__init__', 'pkg.subpkg.__init__',
+                                 'pkg.subpkg.module',
+                                 module_code={'pkg.subpkg': __init__})
+        with mock:
+            with util.import_state(meta_path=[mock]):
+                with self.assertRaises((ZeroDivisionError, ImportError)):
+                    # This raises ImportError on the "from ..subpkg import module"
+                    # line, not sure why.
+                    self.__import__('pkg.subpkg')
+                self.assertNotIn('pkg.subpkg', sys.modules)
+                with self.assertRaises((ZeroDivisionError, ImportError)):
+                    self.__import__('pkg.subpkg.module')
+                self.assertNotIn('pkg.subpkg', sys.modules)
+                # XXX False
+                #self.assertIn('pkg.subpkg.module', sys.modules)
+
+    def test_module_not_package(self):
+        # Try to import a submodule from a non-package should raise ImportError.
+        assert not hasattr(sys, '__path__')
+        with self.assertRaises(ImportError) as cm:
+            self.__import__('sys.no_submodules_here')
+        self.assertEqual(cm.exception.name, 'sys.no_submodules_here')
+
+    def test_module_not_package_but_side_effects(self):
+        # If a module injects something into sys.modules as a side-effect, then
+        # pick up on that fact.
+        name = 'mod'
+        subname = name + '.b'
+        def module_injection():
+            sys.modules[subname] = 'total bunk'
+        mock_spec = util.mock_spec('mod',
+                                         module_code={'mod': module_injection})
+        with mock_spec as mock:
+            with util.import_state(meta_path=[mock]):
+                try:
+                    submodule = self.__import__(subname)
+                finally:
+                    support.unload(subname)
+
+
+(Frozen_ParentTests,
+ Source_ParentTests
+ ) = util.test_both(ParentModuleTests, __import__=util.__import__)
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/import_/test_path.py

@@ -0,0 +1,257 @@
+from .. import util
+
+importlib = util.import_importlib('importlib')
+machinery = util.import_importlib('importlib.machinery')
+
+import os
+import sys
+import tempfile
+from types import ModuleType
+import unittest
+import warnings
+import zipimport
+
+
+class FinderTests:
+
+    """Tests for PathFinder."""
+
+    find = None
+    check_found = None
+
+    def test_failure(self):
+        # Test None returned upon not finding a suitable loader.
+        module = '<test module>'
+        with util.import_state():
+            self.assertIsNone(self.find(module))
+
+    def test_sys_path(self):
+        # Test that sys.path is used when 'path' is None.
+        # Implicitly tests that sys.path_importer_cache is used.
+        module = '<test module>'
+        path = '<test path>'
+        importer = util.mock_spec(module)
+        with util.import_state(path_importer_cache={path: importer},
+                               path=[path]):
+            found = self.find(module)
+            self.check_found(found, importer)
+
+    def test_path(self):
+        # Test that 'path' is used when set.
+        # Implicitly tests that sys.path_importer_cache is used.
+        module = '<test module>'
+        path = '<test path>'
+        importer = util.mock_spec(module)
+        with util.import_state(path_importer_cache={path: importer}):
+            found = self.find(module, [path])
+            self.check_found(found, importer)
+
+    def test_empty_list(self):
+        # An empty list should not count as asking for sys.path.
+        module = 'module'
+        path = '<test path>'
+        importer = util.mock_spec(module)
+        with util.import_state(path_importer_cache={path: importer},
+                               path=[path]):
+            self.assertIsNone(self.find('module', []))
+
+    def test_path_hooks(self):
+        # Test that sys.path_hooks is used.
+        # Test that sys.path_importer_cache is set.
+        module = '<test module>'
+        path = '<test path>'
+        importer = util.mock_spec(module)
+        hook = util.mock_path_hook(path, importer=importer)
+        with util.import_state(path_hooks=[hook]):
+            found = self.find(module, [path])
+            self.check_found(found, importer)
+            self.assertIn(path, sys.path_importer_cache)
+            self.assertIs(sys.path_importer_cache[path], importer)
+
+    def test_empty_path_hooks(self):
+        # Test that if sys.path_hooks is empty a warning is raised,
+        # sys.path_importer_cache gets None set, and PathFinder returns None.
+        path_entry = 'bogus_path'
+        with util.import_state(path_importer_cache={}, path_hooks=[],
+                               path=[path_entry]):
+            with warnings.catch_warnings(record=True) as w:
+                warnings.simplefilter('always')
+                self.assertIsNone(self.find('os'))
+                self.assertIsNone(sys.path_importer_cache[path_entry])
+                self.assertEqual(len(w), 1)
+                self.assertTrue(issubclass(w[-1].category, ImportWarning))
+
+    def test_path_importer_cache_empty_string(self):
+        # The empty string should create a finder using the cwd.
+        path = ''
+        module = '<test module>'
+        importer = util.mock_spec(module)
+        hook = util.mock_path_hook(os.getcwd(), importer=importer)
+        with util.import_state(path=[path], path_hooks=[hook]):
+            found = self.find(module)
+            self.check_found(found, importer)
+            self.assertIn(os.getcwd(), sys.path_importer_cache)
+
+    def test_None_on_sys_path(self):
+        # Putting None in sys.path[0] caused an import regression from Python
+        # 3.2: http://bugs.python.org/issue16514
+        new_path = sys.path[:]
+        new_path.insert(0, None)
+        new_path_importer_cache = sys.path_importer_cache.copy()
+        new_path_importer_cache.pop(None, None)
+        new_path_hooks = [zipimport.zipimporter,
+                          self.machinery.FileFinder.path_hook(
+                              *self.importlib._bootstrap_external._get_supported_file_loaders())]
+        missing = object()
+        email = sys.modules.pop('email', missing)
+        try:
+            with util.import_state(meta_path=sys.meta_path[:],
+                                   path=new_path,
+                                   path_importer_cache=new_path_importer_cache,
+                                   path_hooks=new_path_hooks):
+                module = self.importlib.import_module('email')
+                self.assertIsInstance(module, ModuleType)
+        finally:
+            if email is not missing:
+                sys.modules['email'] = email
+
+    def test_finder_with_find_module(self):
+        class TestFinder:
+            def find_module(self, fullname):
+                return self.to_return
+        failing_finder = TestFinder()
+        failing_finder.to_return = None
+        path = 'testing path'
+        with util.import_state(path_importer_cache={path: failing_finder}):
+            self.assertIsNone(
+                    self.machinery.PathFinder.find_spec('whatever', [path]))
+        success_finder = TestFinder()
+        success_finder.to_return = __loader__
+        with util.import_state(path_importer_cache={path: success_finder}):
+            spec = self.machinery.PathFinder.find_spec('whatever', [path])
+        self.assertEqual(spec.loader, __loader__)
+
+    def test_finder_with_find_loader(self):
+        class TestFinder:
+            loader = None
+            portions = []
+            def find_loader(self, fullname):
+                return self.loader, self.portions
+        path = 'testing path'
+        with util.import_state(path_importer_cache={path: TestFinder()}):
+            self.assertIsNone(
+                    self.machinery.PathFinder.find_spec('whatever', [path]))
+        success_finder = TestFinder()
+        success_finder.loader = __loader__
+        with util.import_state(path_importer_cache={path: success_finder}):
+            spec = self.machinery.PathFinder.find_spec('whatever', [path])
+        self.assertEqual(spec.loader, __loader__)
+
+    def test_finder_with_find_spec(self):
+        class TestFinder:
+            spec = None
+            def find_spec(self, fullname, target=None):
+                return self.spec
+        path = 'testing path'
+        with util.import_state(path_importer_cache={path: TestFinder()}):
+            self.assertIsNone(
+                    self.machinery.PathFinder.find_spec('whatever', [path]))
+        success_finder = TestFinder()
+        success_finder.spec = self.machinery.ModuleSpec('whatever', __loader__)
+        with util.import_state(path_importer_cache={path: success_finder}):
+            got = self.machinery.PathFinder.find_spec('whatever', [path])
+        self.assertEqual(got, success_finder.spec)
+
+    def test_deleted_cwd(self):
+        # Issue #22834
+        old_dir = os.getcwd()
+        self.addCleanup(os.chdir, old_dir)
+        new_dir = tempfile.mkdtemp()
+        try:
+            os.chdir(new_dir)
+            try:
+                os.rmdir(new_dir)
+            except OSError:
+                # EINVAL on Solaris, EBUSY on AIX, ENOTEMPTY on Windows
+                self.skipTest("platform does not allow "
+                              "the deletion of the cwd")
+        except:
+            os.chdir(old_dir)
+            os.rmdir(new_dir)
+            raise
+
+        with util.import_state(path=['']):
+            # Do not want FileNotFoundError raised.
+            self.assertIsNone(self.machinery.PathFinder.find_spec('whatever'))
+
+
+class FindModuleTests(FinderTests):
+    def find(self, *args, **kwargs):
+        return self.machinery.PathFinder.find_module(*args, **kwargs)
+    def check_found(self, found, importer):
+        self.assertIs(found, importer)
+
+
+(Frozen_FindModuleTests,
+ Source_FindModuleTests
+) = util.test_both(FindModuleTests, importlib=importlib, machinery=machinery)
+
+
+class FindSpecTests(FinderTests):
+    def find(self, *args, **kwargs):
+        return self.machinery.PathFinder.find_spec(*args, **kwargs)
+    def check_found(self, found, importer):
+        self.assertIs(found.loader, importer)
+
+
+(Frozen_FindSpecTests,
+ Source_FindSpecTests
+ ) = util.test_both(FindSpecTests, importlib=importlib, machinery=machinery)
+
+
+class PathEntryFinderTests:
+
+    def test_finder_with_failing_find_spec(self):
+        # PathEntryFinder with find_module() defined should work.
+        # Issue #20763.
+        class Finder:
+            path_location = 'test_finder_with_find_module'
+            def __init__(self, path):
+                if path != self.path_location:
+                    raise ImportError
+
+            @staticmethod
+            def find_module(fullname):
+                return None
+
+
+        with util.import_state(path=[Finder.path_location]+sys.path[:],
+                               path_hooks=[Finder]):
+            self.machinery.PathFinder.find_spec('importlib')
+
+    def test_finder_with_failing_find_module(self):
+        # PathEntryFinder with find_module() defined should work.
+        # Issue #20763.
+        class Finder:
+            path_location = 'test_finder_with_find_module'
+            def __init__(self, path):
+                if path != self.path_location:
+                    raise ImportError
+
+            @staticmethod
+            def find_module(fullname):
+                return None
+
+
+        with util.import_state(path=[Finder.path_location]+sys.path[:],
+                               path_hooks=[Finder]):
+            self.machinery.PathFinder.find_module('importlib')
+
+
+(Frozen_PEFTests,
+ Source_PEFTests
+ ) = util.test_both(PathEntryFinderTests, machinery=machinery)
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/import_/test_relative_imports.py

@@ -0,0 +1,232 @@
+"""Test relative imports (PEP 328)."""
+from .. import util
+import unittest
+import warnings
+
+
+class RelativeImports:
+
+    """PEP 328 introduced relative imports. This allows for imports to occur
+    from within a package without having to specify the actual package name.
+
+    A simple example is to import another module within the same package
+    [module from module]::
+
+      # From pkg.mod1 with pkg.mod2 being a module.
+      from . import mod2
+
+    This also works for getting an attribute from a module that is specified
+    in a relative fashion [attr from module]::
+
+      # From pkg.mod1.
+      from .mod2 import attr
+
+    But this is in no way restricted to working between modules; it works
+    from [package to module],::
+
+      # From pkg, importing pkg.module which is a module.
+      from . import module
+
+    [module to package],::
+
+      # Pull attr from pkg, called from pkg.module which is a module.
+      from . import attr
+
+    and [package to package]::
+
+      # From pkg.subpkg1 (both pkg.subpkg[1,2] are packages).
+      from .. import subpkg2
+
+    The number of dots used is in no way restricted [deep import]::
+
+      # Import pkg.attr from pkg.pkg1.pkg2.pkg3.pkg4.pkg5.
+      from ...... import attr
+
+    To prevent someone from accessing code that is outside of a package, one
+    cannot reach the location containing the root package itself::
+
+      # From pkg.__init__ [too high from package]
+      from .. import top_level
+
+      # From pkg.module [too high from module]
+      from .. import top_level
+
+     Relative imports are the only type of import that allow for an empty
+     module name for an import [empty name].
+
+    """
+
+    def relative_import_test(self, create, globals_, callback):
+        """Abstract out boilerplace for setting up for an import test."""
+        uncache_names = []
+        for name in create:
+            if not name.endswith('.__init__'):
+                uncache_names.append(name)
+            else:
+                uncache_names.append(name[:-len('.__init__')])
+        with util.mock_spec(*create) as importer:
+            with util.import_state(meta_path=[importer]):
+                with warnings.catch_warnings():
+                    warnings.simplefilter("ignore")
+                    for global_ in globals_:
+                        with util.uncache(*uncache_names):
+                            callback(global_)
+
+
+    def test_module_from_module(self):
+        # [module from module]
+        create = 'pkg.__init__', 'pkg.mod2'
+        globals_ = {'__package__': 'pkg'}, {'__name__': 'pkg.mod1'}
+        def callback(global_):
+            self.__import__('pkg')  # For __import__().
+            module = self.__import__('', global_, fromlist=['mod2'], level=1)
+            self.assertEqual(module.__name__, 'pkg')
+            self.assertTrue(hasattr(module, 'mod2'))
+            self.assertEqual(module.mod2.attr, 'pkg.mod2')
+        self.relative_import_test(create, globals_, callback)
+
+    def test_attr_from_module(self):
+        # [attr from module]
+        create = 'pkg.__init__', 'pkg.mod2'
+        globals_ = {'__package__': 'pkg'}, {'__name__': 'pkg.mod1'}
+        def callback(global_):
+            self.__import__('pkg')  # For __import__().
+            module = self.__import__('mod2', global_, fromlist=['attr'],
+                                            level=1)
+            self.assertEqual(module.__name__, 'pkg.mod2')
+            self.assertEqual(module.attr, 'pkg.mod2')
+        self.relative_import_test(create, globals_, callback)
+
+    def test_package_to_module(self):
+        # [package to module]
+        create = 'pkg.__init__', 'pkg.module'
+        globals_ = ({'__package__': 'pkg'},
+                    {'__name__': 'pkg', '__path__': ['blah']})
+        def callback(global_):
+            self.__import__('pkg')  # For __import__().
+            module = self.__import__('', global_, fromlist=['module'],
+                             level=1)
+            self.assertEqual(module.__name__, 'pkg')
+            self.assertTrue(hasattr(module, 'module'))
+            self.assertEqual(module.module.attr, 'pkg.module')
+        self.relative_import_test(create, globals_, callback)
+
+    def test_module_to_package(self):
+        # [module to package]
+        create = 'pkg.__init__', 'pkg.module'
+        globals_ = {'__package__': 'pkg'}, {'__name__': 'pkg.module'}
+        def callback(global_):
+            self.__import__('pkg')  # For __import__().
+            module = self.__import__('', global_, fromlist=['attr'], level=1)
+            self.assertEqual(module.__name__, 'pkg')
+        self.relative_import_test(create, globals_, callback)
+
+    def test_package_to_package(self):
+        # [package to package]
+        create = ('pkg.__init__', 'pkg.subpkg1.__init__',
+                    'pkg.subpkg2.__init__')
+        globals_ =  ({'__package__': 'pkg.subpkg1'},
+                     {'__name__': 'pkg.subpkg1', '__path__': ['blah']})
+        def callback(global_):
+            module = self.__import__('', global_, fromlist=['subpkg2'],
+                                            level=2)
+            self.assertEqual(module.__name__, 'pkg')
+            self.assertTrue(hasattr(module, 'subpkg2'))
+            self.assertEqual(module.subpkg2.attr, 'pkg.subpkg2.__init__')
+
+    def test_deep_import(self):
+        # [deep import]
+        create = ['pkg.__init__']
+        for count in range(1,6):
+            create.append('{0}.pkg{1}.__init__'.format(
+                            create[-1][:-len('.__init__')], count))
+        globals_ = ({'__package__': 'pkg.pkg1.pkg2.pkg3.pkg4.pkg5'},
+                    {'__name__': 'pkg.pkg1.pkg2.pkg3.pkg4.pkg5',
+                        '__path__': ['blah']})
+        def callback(global_):
+            self.__import__(globals_[0]['__package__'])
+            module = self.__import__('', global_, fromlist=['attr'], level=6)
+            self.assertEqual(module.__name__, 'pkg')
+        self.relative_import_test(create, globals_, callback)
+
+    def test_too_high_from_package(self):
+        # [too high from package]
+        create = ['top_level', 'pkg.__init__']
+        globals_ = ({'__package__': 'pkg'},
+                    {'__name__': 'pkg', '__path__': ['blah']})
+        def callback(global_):
+            self.__import__('pkg')
+            with self.assertRaises(ValueError):
+                self.__import__('', global_, fromlist=['top_level'],
+                                    level=2)
+        self.relative_import_test(create, globals_, callback)
+
+    def test_too_high_from_module(self):
+        # [too high from module]
+        create = ['top_level', 'pkg.__init__', 'pkg.module']
+        globals_ = {'__package__': 'pkg'}, {'__name__': 'pkg.module'}
+        def callback(global_):
+            self.__import__('pkg')
+            with self.assertRaises(ValueError):
+                self.__import__('', global_, fromlist=['top_level'],
+                                    level=2)
+        self.relative_import_test(create, globals_, callback)
+
+    def test_empty_name_w_level_0(self):
+        # [empty name]
+        with self.assertRaises(ValueError):
+            self.__import__('')
+
+    def test_import_from_different_package(self):
+        # Test importing from a different package than the caller.
+        # in pkg.subpkg1.mod
+        # from ..subpkg2 import mod
+        create = ['__runpy_pkg__.__init__',
+                    '__runpy_pkg__.__runpy_pkg__.__init__',
+                    '__runpy_pkg__.uncle.__init__',
+                    '__runpy_pkg__.uncle.cousin.__init__',
+                    '__runpy_pkg__.uncle.cousin.nephew']
+        globals_ = {'__package__': '__runpy_pkg__.__runpy_pkg__'}
+        def callback(global_):
+            self.__import__('__runpy_pkg__.__runpy_pkg__')
+            module = self.__import__('uncle.cousin', globals_, {},
+                                    fromlist=['nephew'],
+                                level=2)
+            self.assertEqual(module.__name__, '__runpy_pkg__.uncle.cousin')
+        self.relative_import_test(create, globals_, callback)
+
+    def test_import_relative_import_no_fromlist(self):
+        # Import a relative module w/ no fromlist.
+        create = ['crash.__init__', 'crash.mod']
+        globals_ = [{'__package__': 'crash', '__name__': 'crash'}]
+        def callback(global_):
+            self.__import__('crash')
+            mod = self.__import__('mod', global_, {}, [], 1)
+            self.assertEqual(mod.__name__, 'crash.mod')
+        self.relative_import_test(create, globals_, callback)
+
+    def test_relative_import_no_globals(self):
+        # No globals for a relative import is an error.
+        with warnings.catch_warnings():
+            warnings.simplefilter("ignore")
+            with self.assertRaises(KeyError):
+                self.__import__('sys', level=1)
+
+    def test_relative_import_no_package(self):
+        with self.assertRaises(ImportError):
+            self.__import__('a', {'__package__': '', '__spec__': None},
+                            level=1)
+
+    def test_relative_import_no_package_exists_absolute(self):
+        with self.assertRaises(ImportError):
+            self.__import__('sys', {'__package__': '', '__spec__': None},
+                            level=1)
+
+
+(Frozen_RelativeImports,
+ Source_RelativeImports
+ ) = util.test_both(RelativeImports, __import__=util.__import__)
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/namespace_pkgs/both_portions/foo/one.py

@@ -0,0 +1 @@
+attr = 'both_portions foo one'

third_party/python/Lib/test/test_importlib/namespace_pkgs/both_portions/foo/two.py

@@ -0,0 +1 @@
+attr = 'both_portions foo two'

third_party/python/Lib/test/test_importlib/namespace_pkgs/module_and_namespace_package/a_test.py

@@ -0,0 +1 @@
+attr = 'in module'

third_party/python/Lib/test/test_importlib/namespace_pkgs/not_a_namespace_pkg/foo/one.py

@@ -0,0 +1 @@
+attr = 'portion1 foo one'

third_party/python/Lib/test/test_importlib/namespace_pkgs/portion1/foo/one.py

@@ -0,0 +1 @@
+attr = 'portion1 foo one'

third_party/python/Lib/test/test_importlib/namespace_pkgs/portion2/foo/two.py

@@ -0,0 +1 @@
+attr = 'portion2 foo two'

third_party/python/Lib/test/test_importlib/namespace_pkgs/project1/parent/child/one.py

@@ -0,0 +1 @@
+attr = 'parent child one'

third_party/python/Lib/test/test_importlib/namespace_pkgs/project2/parent/child/two.py

@@ -0,0 +1 @@
+attr = 'parent child two'

third_party/python/Lib/test/test_importlib/namespace_pkgs/project3/parent/child/three.py

@@ -0,0 +1 @@
+attr = 'parent child three'

third_party/python/Lib/test/test_importlib/source/__init__.py

@@ -0,0 +1,5 @@
+import os
+from test.support import load_package_tests
+
+def load_tests(*args):
+    return load_package_tests(os.path.dirname(__file__), *args)

third_party/python/Lib/test/test_importlib/source/__main__.py

@@ -0,0 +1,4 @@
+from . import load_tests
+import unittest
+
+unittest.main()

third_party/python/Lib/test/test_importlib/source/test_case_sensitivity.py

@@ -0,0 +1,85 @@
+"""Test case-sensitivity (PEP 235)."""
+from .. import util
+
+importlib = util.import_importlib('importlib')
+machinery = util.import_importlib('importlib.machinery')
+
+import os
+from test import support as test_support
+import unittest
+
+
+@util.case_insensitive_tests
+class CaseSensitivityTest(util.CASEOKTestBase):
+
+    """PEP 235 dictates that on case-preserving, case-insensitive file systems
+    that imports are case-sensitive unless the PYTHONCASEOK environment
+    variable is set."""
+
+    name = 'MoDuLe'
+    assert name != name.lower()
+
+    def finder(self, path):
+        return self.machinery.FileFinder(path,
+                                      (self.machinery.SourceFileLoader,
+                                            self.machinery.SOURCE_SUFFIXES),
+                                        (self.machinery.SourcelessFileLoader,
+                                            self.machinery.BYTECODE_SUFFIXES))
+
+    def sensitivity_test(self):
+        """Look for a module with matching and non-matching sensitivity."""
+        sensitive_pkg = 'sensitive.{0}'.format(self.name)
+        insensitive_pkg = 'insensitive.{0}'.format(self.name.lower())
+        context = util.create_modules(insensitive_pkg, sensitive_pkg)
+        with context as mapping:
+            sensitive_path = os.path.join(mapping['.root'], 'sensitive')
+            insensitive_path = os.path.join(mapping['.root'], 'insensitive')
+            sensitive_finder = self.finder(sensitive_path)
+            insensitive_finder = self.finder(insensitive_path)
+            return self.find(sensitive_finder), self.find(insensitive_finder)
+
+    def test_sensitive(self):
+        with test_support.EnvironmentVarGuard() as env:
+            env.unset('PYTHONCASEOK')
+            self.caseok_env_changed(should_exist=False)
+            sensitive, insensitive = self.sensitivity_test()
+            self.assertIsNotNone(sensitive)
+            self.assertIn(self.name, sensitive.get_filename(self.name))
+            self.assertIsNone(insensitive)
+
+    def test_insensitive(self):
+        with test_support.EnvironmentVarGuard() as env:
+            env.set('PYTHONCASEOK', '1')
+            self.caseok_env_changed(should_exist=True)
+            sensitive, insensitive = self.sensitivity_test()
+            self.assertIsNotNone(sensitive)
+            self.assertIn(self.name, sensitive.get_filename(self.name))
+            self.assertIsNotNone(insensitive)
+            self.assertIn(self.name, insensitive.get_filename(self.name))
+
+
+class CaseSensitivityTestPEP302(CaseSensitivityTest):
+    def find(self, finder):
+        return finder.find_module(self.name)
+
+
+(Frozen_CaseSensitivityTestPEP302,
+ Source_CaseSensitivityTestPEP302
+ ) = util.test_both(CaseSensitivityTestPEP302, importlib=importlib,
+                    machinery=machinery)
+
+
+class CaseSensitivityTestPEP451(CaseSensitivityTest):
+    def find(self, finder):
+        found = finder.find_spec(self.name)
+        return found.loader if found is not None else found
+
+
+(Frozen_CaseSensitivityTestPEP451,
+ Source_CaseSensitivityTestPEP451
+ ) = util.test_both(CaseSensitivityTestPEP451, importlib=importlib,
+                    machinery=machinery)
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/source/test_file_loader.py

@@ -0,0 +1,602 @@
+from .. import abc
+from .. import util
+
+importlib = util.import_importlib('importlib')
+importlib_abc = util.import_importlib('importlib.abc')
+machinery = util.import_importlib('importlib.machinery')
+importlib_util = util.import_importlib('importlib.util')
+
+import errno
+import marshal
+import os
+import py_compile
+import shutil
+import stat
+import sys
+import types
+import unittest
+import warnings
+
+from test.support import make_legacy_pyc, unload
+
+
+class SimpleTest(abc.LoaderTests):
+
+    """Should have no issue importing a source module [basic]. And if there is
+    a syntax error, it should raise a SyntaxError [syntax error].
+
+    """
+
+    def setUp(self):
+        self.name = 'spam'
+        self.filepath = os.path.join('ham', self.name + '.py')
+        self.loader = self.machinery.SourceFileLoader(self.name, self.filepath)
+
+    def test_load_module_API(self):
+        class Tester(self.abc.FileLoader):
+            def get_source(self, _): return 'attr = 42'
+            def is_package(self, _): return False
+
+        loader = Tester('blah', 'blah.py')
+        self.addCleanup(unload, 'blah')
+        with warnings.catch_warnings():
+            warnings.simplefilter('ignore', DeprecationWarning)
+            module = loader.load_module()  # Should not raise an exception.
+
+    def test_get_filename_API(self):
+        # If fullname is not set then assume self.path is desired.
+        class Tester(self.abc.FileLoader):
+            def get_code(self, _): pass
+            def get_source(self, _): pass
+            def is_package(self, _): pass
+            def module_repr(self, _): pass
+
+        path = 'some_path'
+        name = 'some_name'
+        loader = Tester(name, path)
+        self.assertEqual(path, loader.get_filename(name))
+        self.assertEqual(path, loader.get_filename())
+        self.assertEqual(path, loader.get_filename(None))
+        with self.assertRaises(ImportError):
+            loader.get_filename(name + 'XXX')
+
+    def test_equality(self):
+        other = self.machinery.SourceFileLoader(self.name, self.filepath)
+        self.assertEqual(self.loader, other)
+
+    def test_inequality(self):
+        other = self.machinery.SourceFileLoader('_' + self.name, self.filepath)
+        self.assertNotEqual(self.loader, other)
+
+    # [basic]
+    def test_module(self):
+        with util.create_modules('_temp') as mapping:
+            loader = self.machinery.SourceFileLoader('_temp', mapping['_temp'])
+            with warnings.catch_warnings():
+                warnings.simplefilter('ignore', DeprecationWarning)
+                module = loader.load_module('_temp')
+            self.assertIn('_temp', sys.modules)
+            check = {'__name__': '_temp', '__file__': mapping['_temp'],
+                     '__package__': ''}
+            for attr, value in check.items():
+                self.assertEqual(getattr(module, attr), value)
+
+    def test_package(self):
+        with util.create_modules('_pkg.__init__') as mapping:
+            loader = self.machinery.SourceFileLoader('_pkg',
+                                                 mapping['_pkg.__init__'])
+            with warnings.catch_warnings():
+                warnings.simplefilter('ignore', DeprecationWarning)
+                module = loader.load_module('_pkg')
+            self.assertIn('_pkg', sys.modules)
+            check = {'__name__': '_pkg', '__file__': mapping['_pkg.__init__'],
+                     '__path__': [os.path.dirname(mapping['_pkg.__init__'])],
+                     '__package__': '_pkg'}
+            for attr, value in check.items():
+                self.assertEqual(getattr(module, attr), value)
+
+
+    def test_lacking_parent(self):
+        with util.create_modules('_pkg.__init__', '_pkg.mod')as mapping:
+            loader = self.machinery.SourceFileLoader('_pkg.mod',
+                                                    mapping['_pkg.mod'])
+            with warnings.catch_warnings():
+                warnings.simplefilter('ignore', DeprecationWarning)
+                module = loader.load_module('_pkg.mod')
+            self.assertIn('_pkg.mod', sys.modules)
+            check = {'__name__': '_pkg.mod', '__file__': mapping['_pkg.mod'],
+                     '__package__': '_pkg'}
+            for attr, value in check.items():
+                self.assertEqual(getattr(module, attr), value)
+
+    def fake_mtime(self, fxn):
+        """Fake mtime to always be higher than expected."""
+        return lambda name: fxn(name) + 1
+
+    def test_module_reuse(self):
+        with util.create_modules('_temp') as mapping:
+            loader = self.machinery.SourceFileLoader('_temp', mapping['_temp'])
+            with warnings.catch_warnings():
+                warnings.simplefilter('ignore', DeprecationWarning)
+                module = loader.load_module('_temp')
+            module_id = id(module)
+            module_dict_id = id(module.__dict__)
+            with open(mapping['_temp'], 'w') as file:
+                file.write("testing_var = 42\n")
+            with warnings.catch_warnings():
+                warnings.simplefilter('ignore', DeprecationWarning)
+                module = loader.load_module('_temp')
+            self.assertIn('testing_var', module.__dict__,
+                         "'testing_var' not in "
+                            "{0}".format(list(module.__dict__.keys())))
+            self.assertEqual(module, sys.modules['_temp'])
+            self.assertEqual(id(module), module_id)
+            self.assertEqual(id(module.__dict__), module_dict_id)
+
+    def test_state_after_failure(self):
+        # A failed reload should leave the original module intact.
+        attributes = ('__file__', '__path__', '__package__')
+        value = '<test>'
+        name = '_temp'
+        with util.create_modules(name) as mapping:
+            orig_module = types.ModuleType(name)
+            for attr in attributes:
+                setattr(orig_module, attr, value)
+            with open(mapping[name], 'w') as file:
+                file.write('+++ bad syntax +++')
+            loader = self.machinery.SourceFileLoader('_temp', mapping['_temp'])
+            with self.assertRaises(SyntaxError):
+                loader.exec_module(orig_module)
+            for attr in attributes:
+                self.assertEqual(getattr(orig_module, attr), value)
+            with self.assertRaises(SyntaxError):
+                with warnings.catch_warnings():
+                    warnings.simplefilter('ignore', DeprecationWarning)
+                    loader.load_module(name)
+            for attr in attributes:
+                self.assertEqual(getattr(orig_module, attr), value)
+
+    # [syntax error]
+    def test_bad_syntax(self):
+        with util.create_modules('_temp') as mapping:
+            with open(mapping['_temp'], 'w') as file:
+                file.write('=')
+            loader = self.machinery.SourceFileLoader('_temp', mapping['_temp'])
+            with self.assertRaises(SyntaxError):
+                with warnings.catch_warnings():
+                    warnings.simplefilter('ignore', DeprecationWarning)
+                    loader.load_module('_temp')
+            self.assertNotIn('_temp', sys.modules)
+
+    def test_file_from_empty_string_dir(self):
+        # Loading a module found from an empty string entry on sys.path should
+        # not only work, but keep all attributes relative.
+        file_path = '_temp.py'
+        with open(file_path, 'w') as file:
+            file.write("# test file for importlib")
+        try:
+            with util.uncache('_temp'):
+                loader = self.machinery.SourceFileLoader('_temp', file_path)
+                with warnings.catch_warnings():
+                    warnings.simplefilter('ignore', DeprecationWarning)
+                    mod = loader.load_module('_temp')
+                self.assertEqual(file_path, mod.__file__)
+                self.assertEqual(self.util.cache_from_source(file_path),
+                                 mod.__cached__)
+        finally:
+            os.unlink(file_path)
+            pycache = os.path.dirname(self.util.cache_from_source(file_path))
+            if os.path.exists(pycache):
+                shutil.rmtree(pycache)
+
+    @util.writes_bytecode_files
+    def test_timestamp_overflow(self):
+        # When a modification timestamp is larger than 2**32, it should be
+        # truncated rather than raise an OverflowError.
+        with util.create_modules('_temp') as mapping:
+            source = mapping['_temp']
+            compiled = self.util.cache_from_source(source)
+            with open(source, 'w') as f:
+                f.write("x = 5")
+            try:
+                os.utime(source, (2 ** 33 - 5, 2 ** 33 - 5))
+            except OverflowError:
+                self.skipTest("cannot set modification time to large integer")
+            except OSError as e:
+                if e.errno != getattr(errno, 'EOVERFLOW', None):
+                    raise
+                self.skipTest("cannot set modification time to large integer ({})".format(e))
+            loader = self.machinery.SourceFileLoader('_temp', mapping['_temp'])
+            # PEP 451
+            module = types.ModuleType('_temp')
+            module.__spec__ = self.util.spec_from_loader('_temp', loader)
+            loader.exec_module(module)
+            self.assertEqual(module.x, 5)
+            self.assertTrue(os.path.exists(compiled))
+            os.unlink(compiled)
+            # PEP 302
+            with warnings.catch_warnings():
+                warnings.simplefilter('ignore', DeprecationWarning)
+                mod = loader.load_module('_temp')
+            # Sanity checks.
+            self.assertEqual(mod.__cached__, compiled)
+            self.assertEqual(mod.x, 5)
+            # The pyc file was created.
+            self.assertTrue(os.path.exists(compiled))
+
+    def test_unloadable(self):
+        loader = self.machinery.SourceFileLoader('good name', {})
+        module = types.ModuleType('bad name')
+        module.__spec__ = self.machinery.ModuleSpec('bad name', loader)
+        with self.assertRaises(ImportError):
+            loader.exec_module(module)
+        with self.assertRaises(ImportError):
+            with warnings.catch_warnings():
+                warnings.simplefilter('ignore', DeprecationWarning)
+                loader.load_module('bad name')
+
+
+(Frozen_SimpleTest,
+ Source_SimpleTest
+ ) = util.test_both(SimpleTest, importlib=importlib, machinery=machinery,
+                    abc=importlib_abc, util=importlib_util)
+
+
+class BadBytecodeTest:
+
+    def import_(self, file, module_name):
+        raise NotImplementedError
+
+    def manipulate_bytecode(self, name, mapping, manipulator, *,
+                            del_source=False):
+        """Manipulate the bytecode of a module by passing it into a callable
+        that returns what to use as the new bytecode."""
+        try:
+            del sys.modules['_temp']
+        except KeyError:
+            pass
+        py_compile.compile(mapping[name])
+        if not del_source:
+            bytecode_path = self.util.cache_from_source(mapping[name])
+        else:
+            os.unlink(mapping[name])
+            bytecode_path = make_legacy_pyc(mapping[name])
+        if manipulator:
+            with open(bytecode_path, 'rb') as file:
+                bc = file.read()
+                new_bc = manipulator(bc)
+            with open(bytecode_path, 'wb') as file:
+                if new_bc is not None:
+                    file.write(new_bc)
+        return bytecode_path
+
+    def _test_empty_file(self, test, *, del_source=False):
+        with util.create_modules('_temp') as mapping:
+            bc_path = self.manipulate_bytecode('_temp', mapping,
+                                                lambda bc: b'',
+                                                del_source=del_source)
+            test('_temp', mapping, bc_path)
+
+    @util.writes_bytecode_files
+    def _test_partial_magic(self, test, *, del_source=False):
+        # When their are less than 4 bytes to a .pyc, regenerate it if
+        # possible, else raise ImportError.
+        with util.create_modules('_temp') as mapping:
+            bc_path = self.manipulate_bytecode('_temp', mapping,
+                                                lambda bc: bc[:3],
+                                                del_source=del_source)
+            test('_temp', mapping, bc_path)
+
+    def _test_magic_only(self, test, *, del_source=False):
+        with util.create_modules('_temp') as mapping:
+            bc_path = self.manipulate_bytecode('_temp', mapping,
+                                                lambda bc: bc[:4],
+                                                del_source=del_source)
+            test('_temp', mapping, bc_path)
+
+    def _test_partial_timestamp(self, test, *, del_source=False):
+        with util.create_modules('_temp') as mapping:
+            bc_path = self.manipulate_bytecode('_temp', mapping,
+                                                lambda bc: bc[:7],
+                                                del_source=del_source)
+            test('_temp', mapping, bc_path)
+
+    def _test_partial_size(self, test, *, del_source=False):
+        with util.create_modules('_temp') as mapping:
+            bc_path = self.manipulate_bytecode('_temp', mapping,
+                                                lambda bc: bc[:11],
+                                                del_source=del_source)
+            test('_temp', mapping, bc_path)
+
+    def _test_no_marshal(self, *, del_source=False):
+        with util.create_modules('_temp') as mapping:
+            bc_path = self.manipulate_bytecode('_temp', mapping,
+                                                lambda bc: bc[:12],
+                                                del_source=del_source)
+            file_path = mapping['_temp'] if not del_source else bc_path
+            with self.assertRaises(EOFError):
+                self.import_(file_path, '_temp')
+
+    def _test_non_code_marshal(self, *, del_source=False):
+        with util.create_modules('_temp') as mapping:
+            bytecode_path = self.manipulate_bytecode('_temp', mapping,
+                                    lambda bc: bc[:12] + marshal.dumps(b'abcd'),
+                                    del_source=del_source)
+            file_path = mapping['_temp'] if not del_source else bytecode_path
+            with self.assertRaises(ImportError) as cm:
+                self.import_(file_path, '_temp')
+            self.assertEqual(cm.exception.name, '_temp')
+            self.assertEqual(cm.exception.path, bytecode_path)
+
+    def _test_bad_marshal(self, *, del_source=False):
+        with util.create_modules('_temp') as mapping:
+            bytecode_path = self.manipulate_bytecode('_temp', mapping,
+                                                lambda bc: bc[:12] + b'<test>',
+                                                del_source=del_source)
+            file_path = mapping['_temp'] if not del_source else bytecode_path
+            with self.assertRaises(EOFError):
+                self.import_(file_path, '_temp')
+
+    def _test_bad_magic(self, test, *, del_source=False):
+        with util.create_modules('_temp') as mapping:
+            bc_path = self.manipulate_bytecode('_temp', mapping,
+                                    lambda bc: b'\x00\x00\x00\x00' + bc[4:])
+            test('_temp', mapping, bc_path)
+
+
+class BadBytecodeTestPEP451(BadBytecodeTest):
+
+    def import_(self, file, module_name):
+        loader = self.loader(module_name, file)
+        module = types.ModuleType(module_name)
+        module.__spec__ = self.util.spec_from_loader(module_name, loader)
+        loader.exec_module(module)
+
+
+class BadBytecodeTestPEP302(BadBytecodeTest):
+
+    def import_(self, file, module_name):
+        loader = self.loader(module_name, file)
+        with warnings.catch_warnings():
+            warnings.simplefilter('ignore', DeprecationWarning)
+            module = loader.load_module(module_name)
+        self.assertIn(module_name, sys.modules)
+
+
+class SourceLoaderBadBytecodeTest:
+
+    @classmethod
+    def setUpClass(cls):
+        cls.loader = cls.machinery.SourceFileLoader
+
+    @util.writes_bytecode_files
+    def test_empty_file(self):
+        # When a .pyc is empty, regenerate it if possible, else raise
+        # ImportError.
+        def test(name, mapping, bytecode_path):
+            self.import_(mapping[name], name)
+            with open(bytecode_path, 'rb') as file:
+                self.assertGreater(len(file.read()), 12)
+
+        self._test_empty_file(test)
+
+    def test_partial_magic(self):
+        def test(name, mapping, bytecode_path):
+            self.import_(mapping[name], name)
+            with open(bytecode_path, 'rb') as file:
+                self.assertGreater(len(file.read()), 12)
+
+        self._test_partial_magic(test)
+
+    @util.writes_bytecode_files
+    def test_magic_only(self):
+        # When there is only the magic number, regenerate the .pyc if possible,
+        # else raise EOFError.
+        def test(name, mapping, bytecode_path):
+            self.import_(mapping[name], name)
+            with open(bytecode_path, 'rb') as file:
+                self.assertGreater(len(file.read()), 12)
+
+        self._test_magic_only(test)
+
+    @util.writes_bytecode_files
+    def test_bad_magic(self):
+        # When the magic number is different, the bytecode should be
+        # regenerated.
+        def test(name, mapping, bytecode_path):
+            self.import_(mapping[name], name)
+            with open(bytecode_path, 'rb') as bytecode_file:
+                self.assertEqual(bytecode_file.read(4),
+                                 self.util.MAGIC_NUMBER)
+
+        self._test_bad_magic(test)
+
+    @util.writes_bytecode_files
+    def test_partial_timestamp(self):
+        # When the timestamp is partial, regenerate the .pyc, else
+        # raise EOFError.
+        def test(name, mapping, bc_path):
+            self.import_(mapping[name], name)
+            with open(bc_path, 'rb') as file:
+                self.assertGreater(len(file.read()), 12)
+
+        self._test_partial_timestamp(test)
+
+    @util.writes_bytecode_files
+    def test_partial_size(self):
+        # When the size is partial, regenerate the .pyc, else
+        # raise EOFError.
+        def test(name, mapping, bc_path):
+            self.import_(mapping[name], name)
+            with open(bc_path, 'rb') as file:
+                self.assertGreater(len(file.read()), 12)
+
+        self._test_partial_size(test)
+
+    @util.writes_bytecode_files
+    def test_no_marshal(self):
+        # When there is only the magic number and timestamp, raise EOFError.
+        self._test_no_marshal()
+
+    @util.writes_bytecode_files
+    def test_non_code_marshal(self):
+        self._test_non_code_marshal()
+        # XXX ImportError when sourceless
+
+    # [bad marshal]
+    @util.writes_bytecode_files
+    def test_bad_marshal(self):
+        # Bad marshal data should raise a ValueError.
+        self._test_bad_marshal()
+
+    # [bad timestamp]
+    @util.writes_bytecode_files
+    def test_old_timestamp(self):
+        # When the timestamp is older than the source, bytecode should be
+        # regenerated.
+        zeros = b'\x00\x00\x00\x00'
+        with util.create_modules('_temp') as mapping:
+            py_compile.compile(mapping['_temp'])
+            bytecode_path = self.util.cache_from_source(mapping['_temp'])
+            with open(bytecode_path, 'r+b') as bytecode_file:
+                bytecode_file.seek(4)
+                bytecode_file.write(zeros)
+            self.import_(mapping['_temp'], '_temp')
+            source_mtime = os.path.getmtime(mapping['_temp'])
+            source_timestamp = self.importlib._w_long(source_mtime)
+            with open(bytecode_path, 'rb') as bytecode_file:
+                bytecode_file.seek(4)
+                self.assertEqual(bytecode_file.read(4), source_timestamp)
+
+    # [bytecode read-only]
+    @util.writes_bytecode_files
+    def test_read_only_bytecode(self):
+        # When bytecode is read-only but should be rewritten, fail silently.
+        with util.create_modules('_temp') as mapping:
+            # Create bytecode that will need to be re-created.
+            py_compile.compile(mapping['_temp'])
+            bytecode_path = self.util.cache_from_source(mapping['_temp'])
+            with open(bytecode_path, 'r+b') as bytecode_file:
+                bytecode_file.seek(0)
+                bytecode_file.write(b'\x00\x00\x00\x00')
+            # Make the bytecode read-only.
+            os.chmod(bytecode_path,
+                        stat.S_IRUSR | stat.S_IRGRP | stat.S_IROTH)
+            try:
+                # Should not raise OSError!
+                self.import_(mapping['_temp'], '_temp')
+            finally:
+                # Make writable for eventual clean-up.
+                os.chmod(bytecode_path, stat.S_IWUSR)
+
+
+class SourceLoaderBadBytecodeTestPEP451(
+        SourceLoaderBadBytecodeTest, BadBytecodeTestPEP451):
+    pass
+
+
+(Frozen_SourceBadBytecodePEP451,
+ Source_SourceBadBytecodePEP451
+ ) = util.test_both(SourceLoaderBadBytecodeTestPEP451, importlib=importlib,
+                    machinery=machinery, abc=importlib_abc,
+                    util=importlib_util)
+
+
+class SourceLoaderBadBytecodeTestPEP302(
+        SourceLoaderBadBytecodeTest, BadBytecodeTestPEP302):
+    pass
+
+
+(Frozen_SourceBadBytecodePEP302,
+ Source_SourceBadBytecodePEP302
+ ) = util.test_both(SourceLoaderBadBytecodeTestPEP302, importlib=importlib,
+                    machinery=machinery, abc=importlib_abc,
+                    util=importlib_util)
+
+
+class SourcelessLoaderBadBytecodeTest:
+
+    @classmethod
+    def setUpClass(cls):
+        cls.loader = cls.machinery.SourcelessFileLoader
+
+    def test_empty_file(self):
+        def test(name, mapping, bytecode_path):
+            with self.assertRaises(ImportError) as cm:
+                self.import_(bytecode_path, name)
+            self.assertEqual(cm.exception.name, name)
+            self.assertEqual(cm.exception.path, bytecode_path)
+
+        self._test_empty_file(test, del_source=True)
+
+    def test_partial_magic(self):
+        def test(name, mapping, bytecode_path):
+            with self.assertRaises(ImportError) as cm:
+                self.import_(bytecode_path, name)
+            self.assertEqual(cm.exception.name, name)
+            self.assertEqual(cm.exception.path, bytecode_path)
+        self._test_partial_magic(test, del_source=True)
+
+    def test_magic_only(self):
+        def test(name, mapping, bytecode_path):
+            with self.assertRaises(EOFError):
+                self.import_(bytecode_path, name)
+
+        self._test_magic_only(test, del_source=True)
+
+    def test_bad_magic(self):
+        def test(name, mapping, bytecode_path):
+            with self.assertRaises(ImportError) as cm:
+                self.import_(bytecode_path, name)
+            self.assertEqual(cm.exception.name, name)
+            self.assertEqual(cm.exception.path, bytecode_path)
+
+        self._test_bad_magic(test, del_source=True)
+
+    def test_partial_timestamp(self):
+        def test(name, mapping, bytecode_path):
+            with self.assertRaises(EOFError):
+                self.import_(bytecode_path, name)
+
+        self._test_partial_timestamp(test, del_source=True)
+
+    def test_partial_size(self):
+        def test(name, mapping, bytecode_path):
+            with self.assertRaises(EOFError):
+                self.import_(bytecode_path, name)
+
+        self._test_partial_size(test, del_source=True)
+
+    def test_no_marshal(self):
+        self._test_no_marshal(del_source=True)
+
+    def test_non_code_marshal(self):
+        self._test_non_code_marshal(del_source=True)
+
+
+class SourcelessLoaderBadBytecodeTestPEP451(SourcelessLoaderBadBytecodeTest,
+        BadBytecodeTestPEP451):
+    pass
+
+
+(Frozen_SourcelessBadBytecodePEP451,
+ Source_SourcelessBadBytecodePEP451
+ ) = util.test_both(SourcelessLoaderBadBytecodeTestPEP451, importlib=importlib,
+                    machinery=machinery, abc=importlib_abc,
+                    util=importlib_util)
+
+
+class SourcelessLoaderBadBytecodeTestPEP302(SourcelessLoaderBadBytecodeTest,
+        BadBytecodeTestPEP302):
+    pass
+
+
+(Frozen_SourcelessBadBytecodePEP302,
+ Source_SourcelessBadBytecodePEP302
+ ) = util.test_both(SourcelessLoaderBadBytecodeTestPEP302, importlib=importlib,
+                    machinery=machinery, abc=importlib_abc,
+                    util=importlib_util)
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/source/test_finder.py

@@ -0,0 +1,236 @@
+from .. import abc
+from .. import util
+
+machinery = util.import_importlib('importlib.machinery')
+
+import errno
+import os
+import py_compile
+import stat
+import sys
+import tempfile
+from test.support import make_legacy_pyc
+import unittest
+import warnings
+
+
+class FinderTests(abc.FinderTests):
+
+    """For a top-level module, it should just be found directly in the
+    directory being searched. This is true for a directory with source
+    [top-level source], bytecode [top-level bc], or both [top-level both].
+    There is also the possibility that it is a package [top-level package], in
+    which case there will be a directory with the module name and an
+    __init__.py file. If there is a directory without an __init__.py an
+    ImportWarning is returned [empty dir].
+
+    For sub-modules and sub-packages, the same happens as above but only use
+    the tail end of the name [sub module] [sub package] [sub empty].
+
+    When there is a conflict between a package and module having the same name
+    in the same directory, the package wins out [package over module]. This is
+    so that imports of modules within the package can occur rather than trigger
+    an import error.
+
+    When there is a package and module with the same name, always pick the
+    package over the module [package over module]. This is so that imports from
+    the package have the possibility of succeeding.
+
+    """
+
+    def get_finder(self, root):
+        loader_details = [(self.machinery.SourceFileLoader,
+                            self.machinery.SOURCE_SUFFIXES),
+                          (self.machinery.SourcelessFileLoader,
+                            self.machinery.BYTECODE_SUFFIXES)]
+        return self.machinery.FileFinder(root, *loader_details)
+
+    def import_(self, root, module):
+        finder = self.get_finder(root)
+        return self._find(finder, module, loader_only=True)
+
+    def run_test(self, test, create=None, *, compile_=None, unlink=None):
+        """Test the finding of 'test' with the creation of modules listed in
+        'create'.
+
+        Any names listed in 'compile_' are byte-compiled. Modules
+        listed in 'unlink' have their source files deleted.
+
+        """
+        if create is None:
+            create = {test}
+        with util.create_modules(*create) as mapping:
+            if compile_:
+                for name in compile_:
+                    py_compile.compile(mapping[name])
+            if unlink:
+                for name in unlink:
+                    os.unlink(mapping[name])
+                    try:
+                        make_legacy_pyc(mapping[name])
+                    except OSError as error:
+                        # Some tests do not set compile_=True so the source
+                        # module will not get compiled and there will be no
+                        # PEP 3147 pyc file to rename.
+                        if error.errno != errno.ENOENT:
+                            raise
+            loader = self.import_(mapping['.root'], test)
+            self.assertTrue(hasattr(loader, 'load_module'))
+            return loader
+
+    def test_module(self):
+        # [top-level source]
+        self.run_test('top_level')
+        # [top-level bc]
+        self.run_test('top_level', compile_={'top_level'},
+                      unlink={'top_level'})
+        # [top-level both]
+        self.run_test('top_level', compile_={'top_level'})
+
+    # [top-level package]
+    def test_package(self):
+        # Source.
+        self.run_test('pkg', {'pkg.__init__'})
+        # Bytecode.
+        self.run_test('pkg', {'pkg.__init__'}, compile_={'pkg.__init__'},
+                unlink={'pkg.__init__'})
+        # Both.
+        self.run_test('pkg', {'pkg.__init__'}, compile_={'pkg.__init__'})
+
+    # [sub module]
+    def test_module_in_package(self):
+        with util.create_modules('pkg.__init__', 'pkg.sub') as mapping:
+            pkg_dir = os.path.dirname(mapping['pkg.__init__'])
+            loader = self.import_(pkg_dir, 'pkg.sub')
+            self.assertTrue(hasattr(loader, 'load_module'))
+
+    # [sub package]
+    def test_package_in_package(self):
+        context = util.create_modules('pkg.__init__', 'pkg.sub.__init__')
+        with context as mapping:
+            pkg_dir = os.path.dirname(mapping['pkg.__init__'])
+            loader = self.import_(pkg_dir, 'pkg.sub')
+            self.assertTrue(hasattr(loader, 'load_module'))
+
+    # [package over modules]
+    def test_package_over_module(self):
+        name = '_temp'
+        loader = self.run_test(name, {'{0}.__init__'.format(name), name})
+        self.assertIn('__init__', loader.get_filename(name))
+
+    def test_failure(self):
+        with util.create_modules('blah') as mapping:
+            nothing = self.import_(mapping['.root'], 'sdfsadsadf')
+            self.assertIsNone(nothing)
+
+    def test_empty_string_for_dir(self):
+        # The empty string from sys.path means to search in the cwd.
+        finder = self.machinery.FileFinder('', (self.machinery.SourceFileLoader,
+            self.machinery.SOURCE_SUFFIXES))
+        with open('mod.py', 'w') as file:
+            file.write("# test file for importlib")
+        try:
+            loader = self._find(finder, 'mod', loader_only=True)
+            self.assertTrue(hasattr(loader, 'load_module'))
+        finally:
+            os.unlink('mod.py')
+
+    def test_invalidate_caches(self):
+        # invalidate_caches() should reset the mtime.
+        finder = self.machinery.FileFinder('', (self.machinery.SourceFileLoader,
+            self.machinery.SOURCE_SUFFIXES))
+        finder._path_mtime = 42
+        finder.invalidate_caches()
+        self.assertEqual(finder._path_mtime, -1)
+
+    # Regression test for http://bugs.python.org/issue14846
+    def test_dir_removal_handling(self):
+        mod = 'mod'
+        with util.create_modules(mod) as mapping:
+            finder = self.get_finder(mapping['.root'])
+            found = self._find(finder, 'mod', loader_only=True)
+            self.assertIsNotNone(found)
+        found = self._find(finder, 'mod', loader_only=True)
+        self.assertIsNone(found)
+
+    @unittest.skipUnless(sys.platform != 'win32',
+            'os.chmod() does not support the needed arguments under Windows')
+    def test_no_read_directory(self):
+        # Issue #16730
+        tempdir = tempfile.TemporaryDirectory()
+        original_mode = os.stat(tempdir.name).st_mode
+        def cleanup(tempdir):
+            """Cleanup function for the temporary directory.
+
+            Since we muck with the permissions, we want to set them back to
+            their original values to make sure the directory can be properly
+            cleaned up.
+
+            """
+            os.chmod(tempdir.name, original_mode)
+            # If this is not explicitly called then the __del__ method is used,
+            # but since already mucking around might as well explicitly clean
+            # up.
+            tempdir.__exit__(None, None, None)
+        self.addCleanup(cleanup, tempdir)
+        os.chmod(tempdir.name, stat.S_IWUSR | stat.S_IXUSR)
+        finder = self.get_finder(tempdir.name)
+        found = self._find(finder, 'doesnotexist')
+        self.assertEqual(found, self.NOT_FOUND)
+
+    def test_ignore_file(self):
+        # If a directory got changed to a file from underneath us, then don't
+        # worry about looking for submodules.
+        with tempfile.NamedTemporaryFile() as file_obj:
+            finder = self.get_finder(file_obj.name)
+            found = self._find(finder, 'doesnotexist')
+            self.assertEqual(found, self.NOT_FOUND)
+
+
+class FinderTestsPEP451(FinderTests):
+
+    NOT_FOUND = None
+
+    def _find(self, finder, name, loader_only=False):
+        spec = finder.find_spec(name)
+        return spec.loader if spec is not None else spec
+
+
+(Frozen_FinderTestsPEP451,
+ Source_FinderTestsPEP451
+ ) = util.test_both(FinderTestsPEP451, machinery=machinery)
+
+
+class FinderTestsPEP420(FinderTests):
+
+    NOT_FOUND = (None, [])
+
+    def _find(self, finder, name, loader_only=False):
+        with warnings.catch_warnings():
+            warnings.simplefilter("ignore", DeprecationWarning)
+            loader_portions = finder.find_loader(name)
+            return loader_portions[0] if loader_only else loader_portions
+
+
+(Frozen_FinderTestsPEP420,
+ Source_FinderTestsPEP420
+ ) = util.test_both(FinderTestsPEP420, machinery=machinery)
+
+
+class FinderTestsPEP302(FinderTests):
+
+    NOT_FOUND = None
+
+    def _find(self, finder, name, loader_only=False):
+        with warnings.catch_warnings():
+            warnings.simplefilter("ignore", DeprecationWarning)
+            return finder.find_module(name)
+
+
+(Frozen_FinderTestsPEP302,
+ Source_FinderTestsPEP302
+ ) = util.test_both(FinderTestsPEP302, machinery=machinery)
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/source/test_path_hook.py

@@ -0,0 +1,41 @@
+from .. import util
+
+machinery = util.import_importlib('importlib.machinery')
+
+import unittest
+
+
+class PathHookTest:
+
+    """Test the path hook for source."""
+
+    def path_hook(self):
+        return self.machinery.FileFinder.path_hook((self.machinery.SourceFileLoader,
+            self.machinery.SOURCE_SUFFIXES))
+
+    def test_success(self):
+        with util.create_modules('dummy') as mapping:
+            self.assertTrue(hasattr(self.path_hook()(mapping['.root']),
+                                    'find_spec'))
+
+    def test_success_legacy(self):
+        with util.create_modules('dummy') as mapping:
+            self.assertTrue(hasattr(self.path_hook()(mapping['.root']),
+                                    'find_module'))
+
+    def test_empty_string(self):
+        # The empty string represents the cwd.
+        self.assertTrue(hasattr(self.path_hook()(''), 'find_spec'))
+
+    def test_empty_string_legacy(self):
+        # The empty string represents the cwd.
+        self.assertTrue(hasattr(self.path_hook()(''), 'find_module'))
+
+
+(Frozen_PathHookTest,
+ Source_PathHooktest
+ ) = util.test_both(PathHookTest, machinery=machinery)
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/source/test_source_encoding.py

@@ -0,0 +1,175 @@
+from .. import util
+
+machinery = util.import_importlib('importlib.machinery')
+
+import codecs
+import importlib.util
+import re
+import types
+# Because sys.path gets essentially blanked, need to have unicodedata already
+# imported for the parser to use.
+import unicodedata
+import unittest
+import warnings
+
+
+CODING_RE = re.compile(r'^[ \t\f]*#.*?coding[:=][ \t]*([-\w.]+)', re.ASCII)
+
+
+class EncodingTest:
+
+    """PEP 3120 makes UTF-8 the default encoding for source code
+    [default encoding].
+
+    PEP 263 specifies how that can change on a per-file basis. Either the first
+    or second line can contain the encoding line [encoding first line]
+    encoding second line]. If the file has the BOM marker it is considered UTF-8
+    implicitly [BOM]. If any encoding is specified it must be UTF-8, else it is
+    an error [BOM and utf-8][BOM conflict].
+
+    """
+
+    variable = '\u00fc'
+    character = '\u00c9'
+    source_line = "{0} = '{1}'\n".format(variable, character)
+    module_name = '_temp'
+
+    def run_test(self, source):
+        with util.create_modules(self.module_name) as mapping:
+            with open(mapping[self.module_name], 'wb') as file:
+                file.write(source)
+            loader = self.machinery.SourceFileLoader(self.module_name,
+                                                  mapping[self.module_name])
+            return self.load(loader)
+
+    def create_source(self, encoding):
+        encoding_line = "# coding={0}".format(encoding)
+        assert CODING_RE.match(encoding_line)
+        source_lines = [encoding_line.encode('utf-8')]
+        source_lines.append(self.source_line.encode(encoding))
+        return b'\n'.join(source_lines)
+
+    def test_non_obvious_encoding(self):
+        # Make sure that an encoding that has never been a standard one for
+        # Python works.
+        encoding_line = "# coding=koi8-r"
+        assert CODING_RE.match(encoding_line)
+        source = "{0}\na=42\n".format(encoding_line).encode("koi8-r")
+        self.run_test(source)
+
+    # [default encoding]
+    def test_default_encoding(self):
+        self.run_test(self.source_line.encode('utf-8'))
+
+    # [encoding first line]
+    def test_encoding_on_first_line(self):
+        encoding = 'Latin-1'
+        source = self.create_source(encoding)
+        self.run_test(source)
+
+    # [encoding second line]
+    def test_encoding_on_second_line(self):
+        source = b"#/usr/bin/python\n" + self.create_source('Latin-1')
+        self.run_test(source)
+
+    # [BOM]
+    def test_bom(self):
+        self.run_test(codecs.BOM_UTF8 + self.source_line.encode('utf-8'))
+
+    # [BOM and utf-8]
+    def test_bom_and_utf_8(self):
+        source = codecs.BOM_UTF8 + self.create_source('utf-8')
+        self.run_test(source)
+
+    # [BOM conflict]
+    def test_bom_conflict(self):
+        source = codecs.BOM_UTF8 + self.create_source('latin-1')
+        with self.assertRaises(SyntaxError):
+            self.run_test(source)
+
+
+class EncodingTestPEP451(EncodingTest):
+
+    def load(self, loader):
+        module = types.ModuleType(self.module_name)
+        module.__spec__ = importlib.util.spec_from_loader(self.module_name, loader)
+        loader.exec_module(module)
+        return module
+
+
+(Frozen_EncodingTestPEP451,
+ Source_EncodingTestPEP451
+ ) = util.test_both(EncodingTestPEP451, machinery=machinery)
+
+
+class EncodingTestPEP302(EncodingTest):
+
+    def load(self, loader):
+        with warnings.catch_warnings():
+            warnings.simplefilter('ignore', DeprecationWarning)
+            return loader.load_module(self.module_name)
+
+
+(Frozen_EncodingTestPEP302,
+ Source_EncodingTestPEP302
+ ) = util.test_both(EncodingTestPEP302, machinery=machinery)
+
+
+class LineEndingTest:
+
+    r"""Source written with the three types of line endings (\n, \r\n, \r)
+    need to be readable [cr][crlf][lf]."""
+
+    def run_test(self, line_ending):
+        module_name = '_temp'
+        source_lines = [b"a = 42", b"b = -13", b'']
+        source = line_ending.join(source_lines)
+        with util.create_modules(module_name) as mapping:
+            with open(mapping[module_name], 'wb') as file:
+                file.write(source)
+            loader = self.machinery.SourceFileLoader(module_name,
+                                                     mapping[module_name])
+            return self.load(loader, module_name)
+
+    # [cr]
+    def test_cr(self):
+        self.run_test(b'\r')
+
+    # [crlf]
+    def test_crlf(self):
+        self.run_test(b'\r\n')
+
+    # [lf]
+    def test_lf(self):
+        self.run_test(b'\n')
+
+
+class LineEndingTestPEP451(LineEndingTest):
+
+    def load(self, loader, module_name):
+        module = types.ModuleType(module_name)
+        module.__spec__ = importlib.util.spec_from_loader(module_name, loader)
+        loader.exec_module(module)
+        return module
+
+
+(Frozen_LineEndingTestPEP451,
+ Source_LineEndingTestPEP451
+ ) = util.test_both(LineEndingTestPEP451, machinery=machinery)
+
+
+class LineEndingTestPEP302(LineEndingTest):
+
+    def load(self, loader, module_name):
+        with warnings.catch_warnings():
+            warnings.simplefilter('ignore', DeprecationWarning)
+            return loader.load_module(module_name)
+
+
+(Frozen_LineEndingTestPEP302,
+ Source_LineEndingTestPEP302
+ ) = util.test_both(LineEndingTestPEP302, machinery=machinery)
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/test_abc.py

@@ -0,0 +1,953 @@
+import contextlib
+import inspect
+import io
+import marshal
+import os
+import sys
+from test import support
+import types
+import unittest
+from unittest import mock
+import warnings
+
+from . import util as test_util
+
+init = test_util.import_importlib('importlib')
+abc = test_util.import_importlib('importlib.abc')
+machinery = test_util.import_importlib('importlib.machinery')
+util = test_util.import_importlib('importlib.util')
+
+
+##### Inheritance ##############################################################
+class InheritanceTests:
+
+    """Test that the specified class is a subclass/superclass of the expected
+    classes."""
+
+    subclasses = []
+    superclasses = []
+
+    def setUp(self):
+        self.superclasses = [getattr(self.abc, class_name)
+                             for class_name in self.superclass_names]
+        if hasattr(self, 'subclass_names'):
+            # Because test.support.import_fresh_module() creates a new
+            # importlib._bootstrap per module, inheritance checks fail when
+            # checking across module boundaries (i.e. the _bootstrap in abc is
+            # not the same as the one in machinery). That means stealing one of
+            # the modules from the other to make sure the same instance is used.
+            machinery = self.abc.machinery
+            self.subclasses = [getattr(machinery, class_name)
+                               for class_name in self.subclass_names]
+        assert self.subclasses or self.superclasses, self.__class__
+        self.__test = getattr(self.abc, self._NAME)
+
+    def test_subclasses(self):
+        # Test that the expected subclasses inherit.
+        for subclass in self.subclasses:
+            self.assertTrue(issubclass(subclass, self.__test),
+                "{0} is not a subclass of {1}".format(subclass, self.__test))
+
+    def test_superclasses(self):
+        # Test that the class inherits from the expected superclasses.
+        for superclass in self.superclasses:
+            self.assertTrue(issubclass(self.__test, superclass),
+               "{0} is not a superclass of {1}".format(superclass, self.__test))
+
+
+class MetaPathFinder(InheritanceTests):
+    superclass_names = ['Finder']
+    subclass_names = ['BuiltinImporter', 'FrozenImporter', 'PathFinder',
+                      'WindowsRegistryFinder']
+
+
+(Frozen_MetaPathFinderInheritanceTests,
+ Source_MetaPathFinderInheritanceTests
+ ) = test_util.test_both(MetaPathFinder, abc=abc)
+
+
+class PathEntryFinder(InheritanceTests):
+    superclass_names = ['Finder']
+    subclass_names = ['FileFinder']
+
+
+(Frozen_PathEntryFinderInheritanceTests,
+ Source_PathEntryFinderInheritanceTests
+ ) = test_util.test_both(PathEntryFinder, abc=abc)
+
+
+class ResourceLoader(InheritanceTests):
+    superclass_names = ['Loader']
+
+
+(Frozen_ResourceLoaderInheritanceTests,
+ Source_ResourceLoaderInheritanceTests
+ ) = test_util.test_both(ResourceLoader, abc=abc)
+
+
+class InspectLoader(InheritanceTests):
+    superclass_names = ['Loader']
+    subclass_names = ['BuiltinImporter', 'FrozenImporter', 'ExtensionFileLoader']
+
+
+(Frozen_InspectLoaderInheritanceTests,
+ Source_InspectLoaderInheritanceTests
+ ) = test_util.test_both(InspectLoader, abc=abc)
+
+
+class ExecutionLoader(InheritanceTests):
+    superclass_names = ['InspectLoader']
+    subclass_names = ['ExtensionFileLoader']
+
+
+(Frozen_ExecutionLoaderInheritanceTests,
+ Source_ExecutionLoaderInheritanceTests
+ ) = test_util.test_both(ExecutionLoader, abc=abc)
+
+
+class FileLoader(InheritanceTests):
+    superclass_names = ['ResourceLoader', 'ExecutionLoader']
+    subclass_names = ['SourceFileLoader', 'SourcelessFileLoader']
+
+
+(Frozen_FileLoaderInheritanceTests,
+ Source_FileLoaderInheritanceTests
+ ) = test_util.test_both(FileLoader, abc=abc)
+
+
+class SourceLoader(InheritanceTests):
+    superclass_names = ['ResourceLoader', 'ExecutionLoader']
+    subclass_names = ['SourceFileLoader']
+
+
+(Frozen_SourceLoaderInheritanceTests,
+ Source_SourceLoaderInheritanceTests
+ ) = test_util.test_both(SourceLoader, abc=abc)
+
+
+##### Default return values ####################################################
+
+def make_abc_subclasses(base_class, name=None, inst=False, **kwargs):
+    if name is None:
+        name = base_class.__name__
+    base = {kind: getattr(splitabc, name)
+            for kind, splitabc in abc.items()}
+    return {cls._KIND: cls() if inst else cls
+            for cls in test_util.split_frozen(base_class, base, **kwargs)}
+
+
+class ABCTestHarness:
+
+    @property
+    def ins(self):
+        # Lazily set ins on the class.
+        cls = self.SPLIT[self._KIND]
+        ins = cls()
+        self.__class__.ins = ins
+        return ins
+
+
+class MetaPathFinder:
+
+    def find_module(self, fullname, path):
+        return super().find_module(fullname, path)
+
+
+class MetaPathFinderDefaultsTests(ABCTestHarness):
+
+    SPLIT = make_abc_subclasses(MetaPathFinder)
+
+    def test_find_module(self):
+        # Default should return None.
+        self.assertIsNone(self.ins.find_module('something', None))
+
+    def test_invalidate_caches(self):
+        # Calling the method is a no-op.
+        self.ins.invalidate_caches()
+
+
+(Frozen_MPFDefaultTests,
+ Source_MPFDefaultTests
+ ) = test_util.test_both(MetaPathFinderDefaultsTests)
+
+
+class PathEntryFinder:
+
+    def find_loader(self, fullname):
+        return super().find_loader(fullname)
+
+
+class PathEntryFinderDefaultsTests(ABCTestHarness):
+
+    SPLIT = make_abc_subclasses(PathEntryFinder)
+
+    def test_find_loader(self):
+        self.assertEqual((None, []), self.ins.find_loader('something'))
+
+    def find_module(self):
+        self.assertEqual(None, self.ins.find_module('something'))
+
+    def test_invalidate_caches(self):
+        # Should be a no-op.
+        self.ins.invalidate_caches()
+
+
+(Frozen_PEFDefaultTests,
+ Source_PEFDefaultTests
+ ) = test_util.test_both(PathEntryFinderDefaultsTests)
+
+
+class Loader:
+
+    def load_module(self, fullname):
+        return super().load_module(fullname)
+
+
+class LoaderDefaultsTests(ABCTestHarness):
+
+    SPLIT = make_abc_subclasses(Loader)
+
+    def test_create_module(self):
+        spec = 'a spec'
+        self.assertIsNone(self.ins.create_module(spec))
+
+    def test_load_module(self):
+        with self.assertRaises(ImportError):
+            self.ins.load_module('something')
+
+    def test_module_repr(self):
+        mod = types.ModuleType('blah')
+        with self.assertRaises(NotImplementedError):
+            self.ins.module_repr(mod)
+        original_repr = repr(mod)
+        mod.__loader__ = self.ins
+        # Should still return a proper repr.
+        self.assertTrue(repr(mod))
+
+
+(Frozen_LDefaultTests,
+ SourceLDefaultTests
+ ) = test_util.test_both(LoaderDefaultsTests)
+
+
+class ResourceLoader(Loader):
+
+    def get_data(self, path):
+        return super().get_data(path)
+
+
+class ResourceLoaderDefaultsTests(ABCTestHarness):
+
+    SPLIT = make_abc_subclasses(ResourceLoader)
+
+    def test_get_data(self):
+        with self.assertRaises(IOError):
+            self.ins.get_data('/some/path')
+
+
+(Frozen_RLDefaultTests,
+ Source_RLDefaultTests
+ ) = test_util.test_both(ResourceLoaderDefaultsTests)
+
+
+class InspectLoader(Loader):
+
+    def is_package(self, fullname):
+        return super().is_package(fullname)
+
+    def get_source(self, fullname):
+        return super().get_source(fullname)
+
+
+SPLIT_IL = make_abc_subclasses(InspectLoader)
+
+
+class InspectLoaderDefaultsTests(ABCTestHarness):
+
+    SPLIT = SPLIT_IL
+
+    def test_is_package(self):
+        with self.assertRaises(ImportError):
+            self.ins.is_package('blah')
+
+    def test_get_source(self):
+        with self.assertRaises(ImportError):
+            self.ins.get_source('blah')
+
+
+(Frozen_ILDefaultTests,
+ Source_ILDefaultTests
+ ) = test_util.test_both(InspectLoaderDefaultsTests)
+
+
+class ExecutionLoader(InspectLoader):
+
+    def get_filename(self, fullname):
+        return super().get_filename(fullname)
+
+
+SPLIT_EL = make_abc_subclasses(ExecutionLoader)
+
+
+class ExecutionLoaderDefaultsTests(ABCTestHarness):
+
+    SPLIT = SPLIT_EL
+
+    def test_get_filename(self):
+        with self.assertRaises(ImportError):
+            self.ins.get_filename('blah')
+
+
+(Frozen_ELDefaultTests,
+ Source_ELDefaultsTests
+ ) = test_util.test_both(InspectLoaderDefaultsTests)
+
+
+##### MetaPathFinder concrete methods ##########################################
+class MetaPathFinderFindModuleTests:
+
+    @classmethod
+    def finder(cls, spec):
+        class MetaPathSpecFinder(cls.abc.MetaPathFinder):
+
+            def find_spec(self, fullname, path, target=None):
+                self.called_for = fullname, path
+                return spec
+
+        return MetaPathSpecFinder()
+
+    def test_no_spec(self):
+        finder = self.finder(None)
+        path = ['a', 'b', 'c']
+        name = 'blah'
+        found = finder.find_module(name, path)
+        self.assertIsNone(found)
+        self.assertEqual(name, finder.called_for[0])
+        self.assertEqual(path, finder.called_for[1])
+
+    def test_spec(self):
+        loader = object()
+        spec = self.util.spec_from_loader('blah', loader)
+        finder = self.finder(spec)
+        found = finder.find_module('blah', None)
+        self.assertIs(found, spec.loader)
+
+
+(Frozen_MPFFindModuleTests,
+ Source_MPFFindModuleTests
+ ) = test_util.test_both(MetaPathFinderFindModuleTests, abc=abc, util=util)
+
+
+##### PathEntryFinder concrete methods #########################################
+class PathEntryFinderFindLoaderTests:
+
+    @classmethod
+    def finder(cls, spec):
+        class PathEntrySpecFinder(cls.abc.PathEntryFinder):
+
+            def find_spec(self, fullname, target=None):
+                self.called_for = fullname
+                return spec
+
+        return PathEntrySpecFinder()
+
+    def test_no_spec(self):
+        finder = self.finder(None)
+        name = 'blah'
+        found = finder.find_loader(name)
+        self.assertIsNone(found[0])
+        self.assertEqual([], found[1])
+        self.assertEqual(name, finder.called_for)
+
+    def test_spec_with_loader(self):
+        loader = object()
+        spec = self.util.spec_from_loader('blah', loader)
+        finder = self.finder(spec)
+        found = finder.find_loader('blah')
+        self.assertIs(found[0], spec.loader)
+
+    def test_spec_with_portions(self):
+        spec = self.machinery.ModuleSpec('blah', None)
+        paths = ['a', 'b', 'c']
+        spec.submodule_search_locations = paths
+        finder = self.finder(spec)
+        found = finder.find_loader('blah')
+        self.assertIsNone(found[0])
+        self.assertEqual(paths, found[1])
+
+
+(Frozen_PEFFindLoaderTests,
+ Source_PEFFindLoaderTests
+ ) = test_util.test_both(PathEntryFinderFindLoaderTests, abc=abc, util=util,
+                         machinery=machinery)
+
+
+##### Loader concrete methods ##################################################
+class LoaderLoadModuleTests:
+
+    def loader(self):
+        class SpecLoader(self.abc.Loader):
+            found = None
+            def exec_module(self, module):
+                self.found = module
+
+            def is_package(self, fullname):
+                """Force some non-default module state to be set."""
+                return True
+
+        return SpecLoader()
+
+    def test_fresh(self):
+        loader = self.loader()
+        name = 'blah'
+        with test_util.uncache(name):
+            loader.load_module(name)
+            module = loader.found
+            self.assertIs(sys.modules[name], module)
+        self.assertEqual(loader, module.__loader__)
+        self.assertEqual(loader, module.__spec__.loader)
+        self.assertEqual(name, module.__name__)
+        self.assertEqual(name, module.__spec__.name)
+        self.assertIsNotNone(module.__path__)
+        self.assertIsNotNone(module.__path__,
+                             module.__spec__.submodule_search_locations)
+
+    def test_reload(self):
+        name = 'blah'
+        loader = self.loader()
+        module = types.ModuleType(name)
+        module.__spec__ = self.util.spec_from_loader(name, loader)
+        module.__loader__ = loader
+        with test_util.uncache(name):
+            sys.modules[name] = module
+            loader.load_module(name)
+            found = loader.found
+            self.assertIs(found, sys.modules[name])
+            self.assertIs(module, sys.modules[name])
+
+
+(Frozen_LoaderLoadModuleTests,
+ Source_LoaderLoadModuleTests
+ ) = test_util.test_both(LoaderLoadModuleTests, abc=abc, util=util)
+
+
+##### InspectLoader concrete methods ###########################################
+class InspectLoaderSourceToCodeTests:
+
+    def source_to_module(self, data, path=None):
+        """Help with source_to_code() tests."""
+        module = types.ModuleType('blah')
+        loader = self.InspectLoaderSubclass()
+        if path is None:
+            code = loader.source_to_code(data)
+        else:
+            code = loader.source_to_code(data, path)
+        exec(code, module.__dict__)
+        return module
+
+    def test_source_to_code_source(self):
+        # Since compile() can handle strings, so should source_to_code().
+        source = 'attr = 42'
+        module = self.source_to_module(source)
+        self.assertTrue(hasattr(module, 'attr'))
+        self.assertEqual(module.attr, 42)
+
+    def test_source_to_code_bytes(self):
+        # Since compile() can handle bytes, so should source_to_code().
+        source = b'attr = 42'
+        module = self.source_to_module(source)
+        self.assertTrue(hasattr(module, 'attr'))
+        self.assertEqual(module.attr, 42)
+
+    def test_source_to_code_path(self):
+        # Specifying a path should set it for the code object.
+        path = 'path/to/somewhere'
+        loader = self.InspectLoaderSubclass()
+        code = loader.source_to_code('', path)
+        self.assertEqual(code.co_filename, path)
+
+    def test_source_to_code_no_path(self):
+        # Not setting a path should still work and be set to <string> since that
+        # is a pre-existing practice as a default to compile().
+        loader = self.InspectLoaderSubclass()
+        code = loader.source_to_code('')
+        self.assertEqual(code.co_filename, '<string>')
+
+
+(Frozen_ILSourceToCodeTests,
+ Source_ILSourceToCodeTests
+ ) = test_util.test_both(InspectLoaderSourceToCodeTests,
+                         InspectLoaderSubclass=SPLIT_IL)
+
+
+class InspectLoaderGetCodeTests:
+
+    def test_get_code(self):
+        # Test success.
+        module = types.ModuleType('blah')
+        with mock.patch.object(self.InspectLoaderSubclass, 'get_source') as mocked:
+            mocked.return_value = 'attr = 42'
+            loader = self.InspectLoaderSubclass()
+            code = loader.get_code('blah')
+        exec(code, module.__dict__)
+        self.assertEqual(module.attr, 42)
+
+    def test_get_code_source_is_None(self):
+        # If get_source() is None then this should be None.
+        with mock.patch.object(self.InspectLoaderSubclass, 'get_source') as mocked:
+            mocked.return_value = None
+            loader = self.InspectLoaderSubclass()
+            code = loader.get_code('blah')
+        self.assertIsNone(code)
+
+    def test_get_code_source_not_found(self):
+        # If there is no source then there is no code object.
+        loader = self.InspectLoaderSubclass()
+        with self.assertRaises(ImportError):
+            loader.get_code('blah')
+
+
+(Frozen_ILGetCodeTests,
+ Source_ILGetCodeTests
+ ) = test_util.test_both(InspectLoaderGetCodeTests,
+                         InspectLoaderSubclass=SPLIT_IL)
+
+
+class InspectLoaderLoadModuleTests:
+
+    """Test InspectLoader.load_module()."""
+
+    module_name = 'blah'
+
+    def setUp(self):
+        support.unload(self.module_name)
+        self.addCleanup(support.unload, self.module_name)
+
+    def load(self, loader):
+        spec = self.util.spec_from_loader(self.module_name, loader)
+        with warnings.catch_warnings():
+            warnings.simplefilter('ignore', DeprecationWarning)
+            return self.init._bootstrap._load_unlocked(spec)
+
+    def mock_get_code(self):
+        return mock.patch.object(self.InspectLoaderSubclass, 'get_code')
+
+    def test_get_code_ImportError(self):
+        # If get_code() raises ImportError, it should propagate.
+        with self.mock_get_code() as mocked_get_code:
+            mocked_get_code.side_effect = ImportError
+            with self.assertRaises(ImportError):
+                loader = self.InspectLoaderSubclass()
+                self.load(loader)
+
+    def test_get_code_None(self):
+        # If get_code() returns None, raise ImportError.
+        with self.mock_get_code() as mocked_get_code:
+            mocked_get_code.return_value = None
+            with self.assertRaises(ImportError):
+                loader = self.InspectLoaderSubclass()
+                self.load(loader)
+
+    def test_module_returned(self):
+        # The loaded module should be returned.
+        code = compile('attr = 42', '<string>', 'exec')
+        with self.mock_get_code() as mocked_get_code:
+            mocked_get_code.return_value = code
+            loader = self.InspectLoaderSubclass()
+            module = self.load(loader)
+            self.assertEqual(module, sys.modules[self.module_name])
+
+
+(Frozen_ILLoadModuleTests,
+ Source_ILLoadModuleTests
+ ) = test_util.test_both(InspectLoaderLoadModuleTests,
+                         InspectLoaderSubclass=SPLIT_IL,
+                         init=init,
+                         util=util)
+
+
+##### ExecutionLoader concrete methods #########################################
+class ExecutionLoaderGetCodeTests:
+
+    def mock_methods(self, *, get_source=False, get_filename=False):
+        source_mock_context, filename_mock_context = None, None
+        if get_source:
+            source_mock_context = mock.patch.object(self.ExecutionLoaderSubclass,
+                                                    'get_source')
+        if get_filename:
+            filename_mock_context = mock.patch.object(self.ExecutionLoaderSubclass,
+                                                      'get_filename')
+        return source_mock_context, filename_mock_context
+
+    def test_get_code(self):
+        path = 'blah.py'
+        source_mock_context, filename_mock_context = self.mock_methods(
+                get_source=True, get_filename=True)
+        with source_mock_context as source_mock, filename_mock_context as name_mock:
+            source_mock.return_value = 'attr = 42'
+            name_mock.return_value = path
+            loader = self.ExecutionLoaderSubclass()
+            code = loader.get_code('blah')
+        self.assertEqual(code.co_filename, path)
+        module = types.ModuleType('blah')
+        exec(code, module.__dict__)
+        self.assertEqual(module.attr, 42)
+
+    def test_get_code_source_is_None(self):
+        # If get_source() is None then this should be None.
+        source_mock_context, _ = self.mock_methods(get_source=True)
+        with source_mock_context as mocked:
+            mocked.return_value = None
+            loader = self.ExecutionLoaderSubclass()
+            code = loader.get_code('blah')
+        self.assertIsNone(code)
+
+    def test_get_code_source_not_found(self):
+        # If there is no source then there is no code object.
+        loader = self.ExecutionLoaderSubclass()
+        with self.assertRaises(ImportError):
+            loader.get_code('blah')
+
+    def test_get_code_no_path(self):
+        # If get_filename() raises ImportError then simply skip setting the path
+        # on the code object.
+        source_mock_context, filename_mock_context = self.mock_methods(
+                get_source=True, get_filename=True)
+        with source_mock_context as source_mock, filename_mock_context as name_mock:
+            source_mock.return_value = 'attr = 42'
+            name_mock.side_effect = ImportError
+            loader = self.ExecutionLoaderSubclass()
+            code = loader.get_code('blah')
+        self.assertEqual(code.co_filename, '<string>')
+        module = types.ModuleType('blah')
+        exec(code, module.__dict__)
+        self.assertEqual(module.attr, 42)
+
+
+(Frozen_ELGetCodeTests,
+ Source_ELGetCodeTests
+ ) = test_util.test_both(ExecutionLoaderGetCodeTests,
+                         ExecutionLoaderSubclass=SPLIT_EL)
+
+
+##### SourceLoader concrete methods ############################################
+class SourceOnlyLoader:
+
+    # Globals that should be defined for all modules.
+    source = (b"_ = '::'.join([__name__, __file__, __cached__, __package__, "
+              b"repr(__loader__)])")
+
+    def __init__(self, path):
+        self.path = path
+
+    def get_data(self, path):
+        if path != self.path:
+            raise IOError
+        return self.source
+
+    def get_filename(self, fullname):
+        return self.path
+
+    def module_repr(self, module):
+        return '<module>'
+
+
+SPLIT_SOL = make_abc_subclasses(SourceOnlyLoader, 'SourceLoader')
+
+
+class SourceLoader(SourceOnlyLoader):
+
+    source_mtime = 1
+
+    def __init__(self, path, magic=None):
+        super().__init__(path)
+        self.bytecode_path = self.util.cache_from_source(self.path)
+        self.source_size = len(self.source)
+        if magic is None:
+            magic = self.util.MAGIC_NUMBER
+        data = bytearray(magic)
+        data.extend(self.init._w_long(self.source_mtime))
+        data.extend(self.init._w_long(self.source_size))
+        code_object = compile(self.source, self.path, 'exec',
+                                dont_inherit=True)
+        data.extend(marshal.dumps(code_object))
+        self.bytecode = bytes(data)
+        self.written = {}
+
+    def get_data(self, path):
+        if path == self.path:
+            return super().get_data(path)
+        elif path == self.bytecode_path:
+            return self.bytecode
+        else:
+            raise OSError
+
+    def path_stats(self, path):
+        if path != self.path:
+            raise IOError
+        return {'mtime': self.source_mtime, 'size': self.source_size}
+
+    def set_data(self, path, data):
+        self.written[path] = bytes(data)
+        return path == self.bytecode_path
+
+
+SPLIT_SL = make_abc_subclasses(SourceLoader, util=util, init=init)
+
+
+class SourceLoaderTestHarness:
+
+    def setUp(self, *, is_package=True, **kwargs):
+        self.package = 'pkg'
+        if is_package:
+            self.path = os.path.join(self.package, '__init__.py')
+            self.name = self.package
+        else:
+            module_name = 'mod'
+            self.path = os.path.join(self.package, '.'.join(['mod', 'py']))
+            self.name = '.'.join([self.package, module_name])
+        self.cached = self.util.cache_from_source(self.path)
+        self.loader = self.loader_mock(self.path, **kwargs)
+
+    def verify_module(self, module):
+        self.assertEqual(module.__name__, self.name)
+        self.assertEqual(module.__file__, self.path)
+        self.assertEqual(module.__cached__, self.cached)
+        self.assertEqual(module.__package__, self.package)
+        self.assertEqual(module.__loader__, self.loader)
+        values = module._.split('::')
+        self.assertEqual(values[0], self.name)
+        self.assertEqual(values[1], self.path)
+        self.assertEqual(values[2], self.cached)
+        self.assertEqual(values[3], self.package)
+        self.assertEqual(values[4], repr(self.loader))
+
+    def verify_code(self, code_object):
+        module = types.ModuleType(self.name)
+        module.__file__ = self.path
+        module.__cached__ = self.cached
+        module.__package__ = self.package
+        module.__loader__ = self.loader
+        module.__path__ = []
+        exec(code_object, module.__dict__)
+        self.verify_module(module)
+
+
+class SourceOnlyLoaderTests(SourceLoaderTestHarness):
+
+    """Test importlib.abc.SourceLoader for source-only loading.
+
+    Reload testing is subsumed by the tests for
+    importlib.util.module_for_loader.
+
+    """
+
+    def test_get_source(self):
+        # Verify the source code is returned as a string.
+        # If an OSError is raised by get_data then raise ImportError.
+        expected_source = self.loader.source.decode('utf-8')
+        self.assertEqual(self.loader.get_source(self.name), expected_source)
+        def raise_OSError(path):
+            raise OSError
+        self.loader.get_data = raise_OSError
+        with self.assertRaises(ImportError) as cm:
+            self.loader.get_source(self.name)
+        self.assertEqual(cm.exception.name, self.name)
+
+    def test_is_package(self):
+        # Properly detect when loading a package.
+        self.setUp(is_package=False)
+        self.assertFalse(self.loader.is_package(self.name))
+        self.setUp(is_package=True)
+        self.assertTrue(self.loader.is_package(self.name))
+        self.assertFalse(self.loader.is_package(self.name + '.__init__'))
+
+    def test_get_code(self):
+        # Verify the code object is created.
+        code_object = self.loader.get_code(self.name)
+        self.verify_code(code_object)
+
+    def test_source_to_code(self):
+        # Verify the compiled code object.
+        code = self.loader.source_to_code(self.loader.source, self.path)
+        self.verify_code(code)
+
+    def test_load_module(self):
+        # Loading a module should set __name__, __loader__, __package__,
+        # __path__ (for packages), __file__, and __cached__.
+        # The module should also be put into sys.modules.
+        with test_util.uncache(self.name):
+            with warnings.catch_warnings():
+                warnings.simplefilter('ignore', DeprecationWarning)
+                module = self.loader.load_module(self.name)
+            self.verify_module(module)
+            self.assertEqual(module.__path__, [os.path.dirname(self.path)])
+            self.assertIn(self.name, sys.modules)
+
+    def test_package_settings(self):
+        # __package__ needs to be set, while __path__ is set on if the module
+        # is a package.
+        # Testing the values for a package are covered by test_load_module.
+        self.setUp(is_package=False)
+        with test_util.uncache(self.name):
+            with warnings.catch_warnings():
+                warnings.simplefilter('ignore', DeprecationWarning)
+                module = self.loader.load_module(self.name)
+            self.verify_module(module)
+            self.assertFalse(hasattr(module, '__path__'))
+
+    def test_get_source_encoding(self):
+        # Source is considered encoded in UTF-8 by default unless otherwise
+        # specified by an encoding line.
+        source = "_ = 'ü'"
+        self.loader.source = source.encode('utf-8')
+        returned_source = self.loader.get_source(self.name)
+        self.assertEqual(returned_source, source)
+        source = "# coding: latin-1\n_ = ü"
+        self.loader.source = source.encode('latin-1')
+        returned_source = self.loader.get_source(self.name)
+        self.assertEqual(returned_source, source)
+
+
+(Frozen_SourceOnlyLoaderTests,
+ Source_SourceOnlyLoaderTests
+ ) = test_util.test_both(SourceOnlyLoaderTests, util=util,
+                         loader_mock=SPLIT_SOL)
+
+
+@unittest.skipIf(sys.dont_write_bytecode, "sys.dont_write_bytecode is true")
+class SourceLoaderBytecodeTests(SourceLoaderTestHarness):
+
+    """Test importlib.abc.SourceLoader's use of bytecode.
+
+    Source-only testing handled by SourceOnlyLoaderTests.
+
+    """
+
+    def verify_code(self, code_object, *, bytecode_written=False):
+        super().verify_code(code_object)
+        if bytecode_written:
+            self.assertIn(self.cached, self.loader.written)
+            data = bytearray(self.util.MAGIC_NUMBER)
+            data.extend(self.init._w_long(self.loader.source_mtime))
+            data.extend(self.init._w_long(self.loader.source_size))
+            data.extend(marshal.dumps(code_object))
+            self.assertEqual(self.loader.written[self.cached], bytes(data))
+
+    def test_code_with_everything(self):
+        # When everything should work.
+        code_object = self.loader.get_code(self.name)
+        self.verify_code(code_object)
+
+    def test_no_bytecode(self):
+        # If no bytecode exists then move on to the source.
+        self.loader.bytecode_path = "<does not exist>"
+        # Sanity check
+        with self.assertRaises(OSError):
+            bytecode_path = self.util.cache_from_source(self.path)
+            self.loader.get_data(bytecode_path)
+        code_object = self.loader.get_code(self.name)
+        self.verify_code(code_object, bytecode_written=True)
+
+    def test_code_bad_timestamp(self):
+        # Bytecode is only used when the timestamp matches the source EXACTLY.
+        for source_mtime in (0, 2):
+            assert source_mtime != self.loader.source_mtime
+            original = self.loader.source_mtime
+            self.loader.source_mtime = source_mtime
+            # If bytecode is used then EOFError would be raised by marshal.
+            self.loader.bytecode = self.loader.bytecode[8:]
+            code_object = self.loader.get_code(self.name)
+            self.verify_code(code_object, bytecode_written=True)
+            self.loader.source_mtime = original
+
+    def test_code_bad_magic(self):
+        # Skip over bytecode with a bad magic number.
+        self.setUp(magic=b'0000')
+        # If bytecode is used then EOFError would be raised by marshal.
+        self.loader.bytecode = self.loader.bytecode[8:]
+        code_object = self.loader.get_code(self.name)
+        self.verify_code(code_object, bytecode_written=True)
+
+    def test_dont_write_bytecode(self):
+        # Bytecode is not written if sys.dont_write_bytecode is true.
+        # Can assume it is false already thanks to the skipIf class decorator.
+        try:
+            sys.dont_write_bytecode = True
+            self.loader.bytecode_path = "<does not exist>"
+            code_object = self.loader.get_code(self.name)
+            self.assertNotIn(self.cached, self.loader.written)
+        finally:
+            sys.dont_write_bytecode = False
+
+    def test_no_set_data(self):
+        # If set_data is not defined, one can still read bytecode.
+        self.setUp(magic=b'0000')
+        original_set_data = self.loader.__class__.mro()[1].set_data
+        try:
+            del self.loader.__class__.mro()[1].set_data
+            code_object = self.loader.get_code(self.name)
+            self.verify_code(code_object)
+        finally:
+            self.loader.__class__.mro()[1].set_data = original_set_data
+
+    def test_set_data_raises_exceptions(self):
+        # Raising NotImplementedError or OSError is okay for set_data.
+        def raise_exception(exc):
+            def closure(*args, **kwargs):
+                raise exc
+            return closure
+
+        self.setUp(magic=b'0000')
+        self.loader.set_data = raise_exception(NotImplementedError)
+        code_object = self.loader.get_code(self.name)
+        self.verify_code(code_object)
+
+
+(Frozen_SLBytecodeTests,
+ SourceSLBytecodeTests
+ ) = test_util.test_both(SourceLoaderBytecodeTests, init=init, util=util,
+                         loader_mock=SPLIT_SL)
+
+
+class SourceLoaderGetSourceTests:
+
+    """Tests for importlib.abc.SourceLoader.get_source()."""
+
+    def test_default_encoding(self):
+        # Should have no problems with UTF-8 text.
+        name = 'mod'
+        mock = self.SourceOnlyLoaderMock('mod.file')
+        source = 'x = "ü"'
+        mock.source = source.encode('utf-8')
+        returned_source = mock.get_source(name)
+        self.assertEqual(returned_source, source)
+
+    def test_decoded_source(self):
+        # Decoding should work.
+        name = 'mod'
+        mock = self.SourceOnlyLoaderMock("mod.file")
+        source = "# coding: Latin-1\nx='ü'"
+        assert source.encode('latin-1') != source.encode('utf-8')
+        mock.source = source.encode('latin-1')
+        returned_source = mock.get_source(name)
+        self.assertEqual(returned_source, source)
+
+    def test_universal_newlines(self):
+        # PEP 302 says universal newlines should be used.
+        name = 'mod'
+        mock = self.SourceOnlyLoaderMock('mod.file')
+        source = "x = 42\r\ny = -13\r\n"
+        mock.source = source.encode('utf-8')
+        expect = io.IncrementalNewlineDecoder(None, True).decode(source)
+        self.assertEqual(mock.get_source(name), expect)
+
+
+(Frozen_SourceOnlyLoaderGetSourceTests,
+ Source_SourceOnlyLoaderGetSourceTests
+ ) = test_util.test_both(SourceLoaderGetSourceTests,
+                         SourceOnlyLoaderMock=SPLIT_SOL)
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/test_api.py

@@ -0,0 +1,449 @@
+from . import util as test_util
+
+init = test_util.import_importlib('importlib')
+util = test_util.import_importlib('importlib.util')
+machinery = test_util.import_importlib('importlib.machinery')
+
+import os.path
+import sys
+from test import support
+import types
+import unittest
+import warnings
+
+
+class ImportModuleTests:
+
+    """Test importlib.import_module."""
+
+    def test_module_import(self):
+        # Test importing a top-level module.
+        with test_util.mock_modules('top_level') as mock:
+            with test_util.import_state(meta_path=[mock]):
+                module = self.init.import_module('top_level')
+                self.assertEqual(module.__name__, 'top_level')
+
+    def test_absolute_package_import(self):
+        # Test importing a module from a package with an absolute name.
+        pkg_name = 'pkg'
+        pkg_long_name = '{0}.__init__'.format(pkg_name)
+        name = '{0}.mod'.format(pkg_name)
+        with test_util.mock_modules(pkg_long_name, name) as mock:
+            with test_util.import_state(meta_path=[mock]):
+                module = self.init.import_module(name)
+                self.assertEqual(module.__name__, name)
+
+    def test_shallow_relative_package_import(self):
+        # Test importing a module from a package through a relative import.
+        pkg_name = 'pkg'
+        pkg_long_name = '{0}.__init__'.format(pkg_name)
+        module_name = 'mod'
+        absolute_name = '{0}.{1}'.format(pkg_name, module_name)
+        relative_name = '.{0}'.format(module_name)
+        with test_util.mock_modules(pkg_long_name, absolute_name) as mock:
+            with test_util.import_state(meta_path=[mock]):
+                self.init.import_module(pkg_name)
+                module = self.init.import_module(relative_name, pkg_name)
+                self.assertEqual(module.__name__, absolute_name)
+
+    def test_deep_relative_package_import(self):
+        modules = ['a.__init__', 'a.b.__init__', 'a.c']
+        with test_util.mock_modules(*modules) as mock:
+            with test_util.import_state(meta_path=[mock]):
+                self.init.import_module('a')
+                self.init.import_module('a.b')
+                module = self.init.import_module('..c', 'a.b')
+                self.assertEqual(module.__name__, 'a.c')
+
+    def test_absolute_import_with_package(self):
+        # Test importing a module from a package with an absolute name with
+        # the 'package' argument given.
+        pkg_name = 'pkg'
+        pkg_long_name = '{0}.__init__'.format(pkg_name)
+        name = '{0}.mod'.format(pkg_name)
+        with test_util.mock_modules(pkg_long_name, name) as mock:
+            with test_util.import_state(meta_path=[mock]):
+                self.init.import_module(pkg_name)
+                module = self.init.import_module(name, pkg_name)
+                self.assertEqual(module.__name__, name)
+
+    def test_relative_import_wo_package(self):
+        # Relative imports cannot happen without the 'package' argument being
+        # set.
+        with self.assertRaises(TypeError):
+            self.init.import_module('.support')
+
+
+    def test_loaded_once(self):
+        # Issue #13591: Modules should only be loaded once when
+        # initializing the parent package attempts to import the
+        # module currently being imported.
+        b_load_count = 0
+        def load_a():
+            self.init.import_module('a.b')
+        def load_b():
+            nonlocal b_load_count
+            b_load_count += 1
+        code = {'a': load_a, 'a.b': load_b}
+        modules = ['a.__init__', 'a.b']
+        with test_util.mock_modules(*modules, module_code=code) as mock:
+            with test_util.import_state(meta_path=[mock]):
+                self.init.import_module('a.b')
+        self.assertEqual(b_load_count, 1)
+
+
+(Frozen_ImportModuleTests,
+ Source_ImportModuleTests
+ ) = test_util.test_both(ImportModuleTests, init=init)
+
+
+class FindLoaderTests:
+
+    FakeMetaFinder = None
+
+    def test_sys_modules(self):
+        # If a module with __loader__ is in sys.modules, then return it.
+        name = 'some_mod'
+        with test_util.uncache(name):
+            module = types.ModuleType(name)
+            loader = 'a loader!'
+            module.__loader__ = loader
+            sys.modules[name] = module
+            with warnings.catch_warnings():
+                warnings.simplefilter('ignore', DeprecationWarning)
+                found = self.init.find_loader(name)
+            self.assertEqual(loader, found)
+
+    def test_sys_modules_loader_is_None(self):
+        # If sys.modules[name].__loader__ is None, raise ValueError.
+        name = 'some_mod'
+        with test_util.uncache(name):
+            module = types.ModuleType(name)
+            module.__loader__ = None
+            sys.modules[name] = module
+            with self.assertRaises(ValueError):
+                with warnings.catch_warnings():
+                    warnings.simplefilter('ignore', DeprecationWarning)
+                    self.init.find_loader(name)
+
+    def test_sys_modules_loader_is_not_set(self):
+        # Should raise ValueError
+        # Issue #17099
+        name = 'some_mod'
+        with test_util.uncache(name):
+            module = types.ModuleType(name)
+            try:
+                del module.__loader__
+            except AttributeError:
+                pass
+            sys.modules[name] = module
+            with self.assertRaises(ValueError):
+                with warnings.catch_warnings():
+                    warnings.simplefilter('ignore', DeprecationWarning)
+                    self.init.find_loader(name)
+
+    def test_success(self):
+        # Return the loader found on sys.meta_path.
+        name = 'some_mod'
+        with test_util.uncache(name):
+            with test_util.import_state(meta_path=[self.FakeMetaFinder]):
+                with warnings.catch_warnings():
+                    warnings.simplefilter('ignore', DeprecationWarning)
+                    self.assertEqual((name, None), self.init.find_loader(name))
+
+    def test_success_path(self):
+        # Searching on a path should work.
+        name = 'some_mod'
+        path = 'path to some place'
+        with test_util.uncache(name):
+            with test_util.import_state(meta_path=[self.FakeMetaFinder]):
+                with warnings.catch_warnings():
+                    warnings.simplefilter('ignore', DeprecationWarning)
+                    self.assertEqual((name, path),
+                                     self.init.find_loader(name, path))
+
+    def test_nothing(self):
+        # None is returned upon failure to find a loader.
+        with warnings.catch_warnings():
+            warnings.simplefilter('ignore', DeprecationWarning)
+            self.assertIsNone(self.init.find_loader('nevergoingtofindthismodule'))
+
+
+class FindLoaderPEP451Tests(FindLoaderTests):
+
+    class FakeMetaFinder:
+        @staticmethod
+        def find_spec(name, path=None, target=None):
+            return machinery['Source'].ModuleSpec(name, (name, path))
+
+
+(Frozen_FindLoaderPEP451Tests,
+ Source_FindLoaderPEP451Tests
+ ) = test_util.test_both(FindLoaderPEP451Tests, init=init)
+
+
+class FindLoaderPEP302Tests(FindLoaderTests):
+
+    class FakeMetaFinder:
+        @staticmethod
+        def find_module(name, path=None):
+            return name, path
+
+
+(Frozen_FindLoaderPEP302Tests,
+ Source_FindLoaderPEP302Tests
+ ) = test_util.test_both(FindLoaderPEP302Tests, init=init)
+
+
+class ReloadTests:
+
+    """Test module reloading for builtin and extension modules."""
+
+    def test_reload_modules(self):
+        for mod in ('tokenize', 'time', 'marshal'):
+            with self.subTest(module=mod):
+                with support.CleanImport(mod):
+                    module = self.init.import_module(mod)
+                    self.init.reload(module)
+
+    def test_module_replaced(self):
+        def code():
+            import sys
+            module = type(sys)('top_level')
+            module.spam = 3
+            sys.modules['top_level'] = module
+        mock = test_util.mock_modules('top_level',
+                                      module_code={'top_level': code})
+        with mock:
+            with test_util.import_state(meta_path=[mock]):
+                module = self.init.import_module('top_level')
+                reloaded = self.init.reload(module)
+                actual = sys.modules['top_level']
+                self.assertEqual(actual.spam, 3)
+                self.assertEqual(reloaded.spam, 3)
+
+    def test_reload_missing_loader(self):
+        with support.CleanImport('types'):
+            import types
+            loader = types.__loader__
+            del types.__loader__
+            reloaded = self.init.reload(types)
+
+            self.assertIs(reloaded, types)
+            self.assertIs(sys.modules['types'], types)
+            self.assertEqual(reloaded.__loader__.path, loader.path)
+
+    def test_reload_loader_replaced(self):
+        with support.CleanImport('types'):
+            import types
+            types.__loader__ = None
+            self.init.invalidate_caches()
+            reloaded = self.init.reload(types)
+
+            self.assertIsNot(reloaded.__loader__, None)
+            self.assertIs(reloaded, types)
+            self.assertIs(sys.modules['types'], types)
+
+    def test_reload_location_changed(self):
+        name = 'spam'
+        with support.temp_cwd(None) as cwd:
+            with test_util.uncache('spam'):
+                with support.DirsOnSysPath(cwd):
+                    # Start as a plain module.
+                    self.init.invalidate_caches()
+                    path = os.path.join(cwd, name + '.py')
+                    cached = self.util.cache_from_source(path)
+                    expected = {'__name__': name,
+                                '__package__': '',
+                                '__file__': path,
+                                '__cached__': cached,
+                                '__doc__': None,
+                                }
+                    support.create_empty_file(path)
+                    module = self.init.import_module(name)
+                    ns = vars(module).copy()
+                    loader = ns.pop('__loader__')
+                    spec = ns.pop('__spec__')
+                    ns.pop('__builtins__', None)  # An implementation detail.
+                    self.assertEqual(spec.name, name)
+                    self.assertEqual(spec.loader, loader)
+                    self.assertEqual(loader.path, path)
+                    self.assertEqual(ns, expected)
+
+                    # Change to a package.
+                    self.init.invalidate_caches()
+                    init_path = os.path.join(cwd, name, '__init__.py')
+                    cached = self.util.cache_from_source(init_path)
+                    expected = {'__name__': name,
+                                '__package__': name,
+                                '__file__': init_path,
+                                '__cached__': cached,
+                                '__path__': [os.path.dirname(init_path)],
+                                '__doc__': None,
+                                }
+                    os.mkdir(name)
+                    os.rename(path, init_path)
+                    reloaded = self.init.reload(module)
+                    ns = vars(reloaded).copy()
+                    loader = ns.pop('__loader__')
+                    spec = ns.pop('__spec__')
+                    ns.pop('__builtins__', None)  # An implementation detail.
+                    self.assertEqual(spec.name, name)
+                    self.assertEqual(spec.loader, loader)
+                    self.assertIs(reloaded, module)
+                    self.assertEqual(loader.path, init_path)
+                    self.maxDiff = None
+                    self.assertEqual(ns, expected)
+
+    def test_reload_namespace_changed(self):
+        name = 'spam'
+        with support.temp_cwd(None) as cwd:
+            with test_util.uncache('spam'):
+                with support.DirsOnSysPath(cwd):
+                    # Start as a namespace package.
+                    self.init.invalidate_caches()
+                    bad_path = os.path.join(cwd, name, '__init.py')
+                    cached = self.util.cache_from_source(bad_path)
+                    expected = {'__name__': name,
+                                '__package__': name,
+                                '__doc__': None,
+                                }
+                    os.mkdir(name)
+                    with open(bad_path, 'w') as init_file:
+                        init_file.write('eggs = None')
+                    module = self.init.import_module(name)
+                    ns = vars(module).copy()
+                    loader = ns.pop('__loader__')
+                    path = ns.pop('__path__')
+                    spec = ns.pop('__spec__')
+                    ns.pop('__builtins__', None)  # An implementation detail.
+                    self.assertEqual(spec.name, name)
+                    self.assertIs(spec.loader, None)
+                    self.assertIsNot(loader, None)
+                    self.assertEqual(set(path),
+                                     set([os.path.dirname(bad_path)]))
+                    with self.assertRaises(AttributeError):
+                        # a NamespaceLoader
+                        loader.path
+                    self.assertEqual(ns, expected)
+
+                    # Change to a regular package.
+                    self.init.invalidate_caches()
+                    init_path = os.path.join(cwd, name, '__init__.py')
+                    cached = self.util.cache_from_source(init_path)
+                    expected = {'__name__': name,
+                                '__package__': name,
+                                '__file__': init_path,
+                                '__cached__': cached,
+                                '__path__': [os.path.dirname(init_path)],
+                                '__doc__': None,
+                                'eggs': None,
+                                }
+                    os.rename(bad_path, init_path)
+                    reloaded = self.init.reload(module)
+                    ns = vars(reloaded).copy()
+                    loader = ns.pop('__loader__')
+                    spec = ns.pop('__spec__')
+                    ns.pop('__builtins__', None)  # An implementation detail.
+                    self.assertEqual(spec.name, name)
+                    self.assertEqual(spec.loader, loader)
+                    self.assertIs(reloaded, module)
+                    self.assertEqual(loader.path, init_path)
+                    self.assertEqual(ns, expected)
+
+    def test_reload_submodule(self):
+        # See #19851.
+        name = 'spam'
+        subname = 'ham'
+        with test_util.temp_module(name, pkg=True) as pkg_dir:
+            fullname, _ = test_util.submodule(name, subname, pkg_dir)
+            ham = self.init.import_module(fullname)
+            reloaded = self.init.reload(ham)
+            self.assertIs(reloaded, ham)
+
+
+(Frozen_ReloadTests,
+ Source_ReloadTests
+ ) = test_util.test_both(ReloadTests, init=init, util=util)
+
+
+class InvalidateCacheTests:
+
+    def test_method_called(self):
+        # If defined the method should be called.
+        class InvalidatingNullFinder:
+            def __init__(self, *ignored):
+                self.called = False
+            def find_module(self, *args):
+                return None
+            def invalidate_caches(self):
+                self.called = True
+
+        key = 'gobledeegook'
+        meta_ins = InvalidatingNullFinder()
+        path_ins = InvalidatingNullFinder()
+        sys.meta_path.insert(0, meta_ins)
+        self.addCleanup(lambda: sys.path_importer_cache.__delitem__(key))
+        sys.path_importer_cache[key] = path_ins
+        self.addCleanup(lambda: sys.meta_path.remove(meta_ins))
+        self.init.invalidate_caches()
+        self.assertTrue(meta_ins.called)
+        self.assertTrue(path_ins.called)
+
+    def test_method_lacking(self):
+        # There should be no issues if the method is not defined.
+        key = 'gobbledeegook'
+        sys.path_importer_cache[key] = None
+        self.addCleanup(lambda: sys.path_importer_cache.__delitem__(key))
+        self.init.invalidate_caches()  # Shouldn't trigger an exception.
+
+
+(Frozen_InvalidateCacheTests,
+ Source_InvalidateCacheTests
+ ) = test_util.test_both(InvalidateCacheTests, init=init)
+
+
+class FrozenImportlibTests(unittest.TestCase):
+
+    def test_no_frozen_importlib(self):
+        # Should be able to import w/o _frozen_importlib being defined.
+        # Can't do an isinstance() check since separate copies of importlib
+        # may have been used for import, so just check the name is not for the
+        # frozen loader.
+        source_init = init['Source']
+        self.assertNotEqual(source_init.__loader__.__class__.__name__,
+                            'FrozenImporter')
+
+
+class StartupTests:
+
+    def test_everyone_has___loader__(self):
+        # Issue #17098: all modules should have __loader__ defined.
+        for name, module in sys.modules.items():
+            if isinstance(module, types.ModuleType):
+                with self.subTest(name=name):
+                    self.assertTrue(hasattr(module, '__loader__'),
+                                    '{!r} lacks a __loader__ attribute'.format(name))
+                    if self.machinery.BuiltinImporter.find_module(name):
+                        self.assertIsNot(module.__loader__, None)
+                    elif self.machinery.FrozenImporter.find_module(name):
+                        self.assertIsNot(module.__loader__, None)
+
+    def test_everyone_has___spec__(self):
+        for name, module in sys.modules.items():
+            if isinstance(module, types.ModuleType):
+                with self.subTest(name=name):
+                    self.assertTrue(hasattr(module, '__spec__'))
+                    if self.machinery.BuiltinImporter.find_module(name):
+                        self.assertIsNot(module.__spec__, None)
+                    elif self.machinery.FrozenImporter.find_module(name):
+                        self.assertIsNot(module.__spec__, None)
+
+
+(Frozen_StartupTests,
+ Source_StartupTests
+ ) = test_util.test_both(StartupTests, machinery=machinery)
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/test_lazy.py

@@ -0,0 +1,145 @@
+import importlib
+from importlib import abc
+from importlib import util
+import sys
+import types
+import unittest
+
+from . import util as test_util
+
+
+class CollectInit:
+
+    def __init__(self, *args, **kwargs):
+        self.args = args
+        self.kwargs = kwargs
+
+    def exec_module(self, module):
+        return self
+
+
+class LazyLoaderFactoryTests(unittest.TestCase):
+
+    def test_init(self):
+        factory = util.LazyLoader.factory(CollectInit)
+        # E.g. what importlib.machinery.FileFinder instantiates loaders with
+        # plus keyword arguments.
+        lazy_loader = factory('module name', 'module path', kw='kw')
+        loader = lazy_loader.loader
+        self.assertEqual(('module name', 'module path'), loader.args)
+        self.assertEqual({'kw': 'kw'}, loader.kwargs)
+
+    def test_validation(self):
+        # No exec_module(), no lazy loading.
+        with self.assertRaises(TypeError):
+            util.LazyLoader.factory(object)
+
+
+class TestingImporter(abc.MetaPathFinder, abc.Loader):
+
+    module_name = 'lazy_loader_test'
+    mutated_name = 'changed'
+    loaded = None
+    source_code = 'attr = 42; __name__ = {!r}'.format(mutated_name)
+
+    def find_spec(self, name, path, target=None):
+        if name != self.module_name:
+            return None
+        return util.spec_from_loader(name, util.LazyLoader(self))
+
+    def exec_module(self, module):
+        exec(self.source_code, module.__dict__)
+        self.loaded = module
+
+
+class LazyLoaderTests(unittest.TestCase):
+
+    def test_init(self):
+        with self.assertRaises(TypeError):
+            # Classes that dono't define exec_module() trigger TypeError.
+            util.LazyLoader(object)
+
+    def new_module(self, source_code=None):
+        loader = TestingImporter()
+        if source_code is not None:
+            loader.source_code = source_code
+        spec = util.spec_from_loader(TestingImporter.module_name,
+                                     util.LazyLoader(loader))
+        module = spec.loader.create_module(spec)
+        if module is None:
+            module = types.ModuleType(TestingImporter.module_name)
+        module.__spec__ = spec
+        module.__loader__ = spec.loader
+        spec.loader.exec_module(module)
+        # Module is now lazy.
+        self.assertIsNone(loader.loaded)
+        return module
+
+    def test_e2e(self):
+        # End-to-end test to verify the load is in fact lazy.
+        importer = TestingImporter()
+        assert importer.loaded is None
+        with test_util.uncache(importer.module_name):
+            with test_util.import_state(meta_path=[importer]):
+                module = importlib.import_module(importer.module_name)
+        self.assertIsNone(importer.loaded)
+        # Trigger load.
+        self.assertEqual(module.__loader__, importer)
+        self.assertIsNotNone(importer.loaded)
+        self.assertEqual(module, importer.loaded)
+
+    def test_attr_unchanged(self):
+        # An attribute only mutated as a side-effect of import should not be
+        # changed needlessly.
+        module = self.new_module()
+        self.assertEqual(TestingImporter.mutated_name, module.__name__)
+
+    def test_new_attr(self):
+        # A new attribute should persist.
+        module = self.new_module()
+        module.new_attr = 42
+        self.assertEqual(42, module.new_attr)
+
+    def test_mutated_preexisting_attr(self):
+        # Changing an attribute that already existed on the module --
+        # e.g. __name__ -- should persist.
+        module = self.new_module()
+        module.__name__ = 'bogus'
+        self.assertEqual('bogus', module.__name__)
+
+    def test_mutated_attr(self):
+        # Changing an attribute that comes into existence after an import
+        # should persist.
+        module = self.new_module()
+        module.attr = 6
+        self.assertEqual(6, module.attr)
+
+    def test_delete_eventual_attr(self):
+        # Deleting an attribute should stay deleted.
+        module = self.new_module()
+        del module.attr
+        self.assertFalse(hasattr(module, 'attr'))
+
+    def test_delete_preexisting_attr(self):
+        module = self.new_module()
+        del module.__name__
+        self.assertFalse(hasattr(module, '__name__'))
+
+    def test_module_substitution_error(self):
+        with test_util.uncache(TestingImporter.module_name):
+            fresh_module = types.ModuleType(TestingImporter.module_name)
+            sys.modules[TestingImporter.module_name] = fresh_module
+            module = self.new_module()
+            with self.assertRaisesRegex(ValueError, "substituted"):
+                module.__name__
+
+    def test_module_already_in_sys(self):
+        with test_util.uncache(TestingImporter.module_name):
+            module = self.new_module()
+            sys.modules[TestingImporter.module_name] = module
+            # Force the load; just care that no exception is raised.
+            module.__name__
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/test_locks.py

@@ -0,0 +1,175 @@
+from . import util as test_util
+
+init = test_util.import_importlib('importlib')
+
+import sys
+import unittest
+import weakref
+
+from test import support
+
+try:
+    import threading
+except ImportError:
+    threading = None
+else:
+    from test import lock_tests
+
+if threading is not None:
+    class ModuleLockAsRLockTests:
+        locktype = classmethod(lambda cls: cls.LockType("some_lock"))
+
+        # _is_owned() unsupported
+        test__is_owned = None
+        # acquire(blocking=False) unsupported
+        test_try_acquire = None
+        test_try_acquire_contended = None
+        # `with` unsupported
+        test_with = None
+        # acquire(timeout=...) unsupported
+        test_timeout = None
+        # _release_save() unsupported
+        test_release_save_unacquired = None
+        # lock status in repr unsupported
+        test_repr = None
+        test_locked_repr = None
+
+    LOCK_TYPES = {kind: splitinit._bootstrap._ModuleLock
+                  for kind, splitinit in init.items()}
+
+    (Frozen_ModuleLockAsRLockTests,
+     Source_ModuleLockAsRLockTests
+     ) = test_util.test_both(ModuleLockAsRLockTests, lock_tests.RLockTests,
+                             LockType=LOCK_TYPES)
+else:
+    LOCK_TYPES = {}
+
+    class Frozen_ModuleLockAsRLockTests(unittest.TestCase):
+        pass
+
+    class Source_ModuleLockAsRLockTests(unittest.TestCase):
+        pass
+
+
+if threading is not None:
+    class DeadlockAvoidanceTests:
+
+        def setUp(self):
+            try:
+                self.old_switchinterval = sys.getswitchinterval()
+                support.setswitchinterval(0.000001)
+            except AttributeError:
+                self.old_switchinterval = None
+
+        def tearDown(self):
+            if self.old_switchinterval is not None:
+                sys.setswitchinterval(self.old_switchinterval)
+
+        def run_deadlock_avoidance_test(self, create_deadlock):
+            NLOCKS = 10
+            locks = [self.LockType(str(i)) for i in range(NLOCKS)]
+            pairs = [(locks[i], locks[(i+1)%NLOCKS]) for i in range(NLOCKS)]
+            if create_deadlock:
+                NTHREADS = NLOCKS
+            else:
+                NTHREADS = NLOCKS - 1
+            barrier = threading.Barrier(NTHREADS)
+            results = []
+
+            def _acquire(lock):
+                """Try to acquire the lock. Return True on success,
+                False on deadlock."""
+                try:
+                    lock.acquire()
+                except self.DeadlockError:
+                    return False
+                else:
+                    return True
+
+            def f():
+                a, b = pairs.pop()
+                ra = _acquire(a)
+                barrier.wait()
+                rb = _acquire(b)
+                results.append((ra, rb))
+                if rb:
+                    b.release()
+                if ra:
+                    a.release()
+            lock_tests.Bunch(f, NTHREADS).wait_for_finished()
+            self.assertEqual(len(results), NTHREADS)
+            return results
+
+        def test_deadlock(self):
+            results = self.run_deadlock_avoidance_test(True)
+            # At least one of the threads detected a potential deadlock on its
+            # second acquire() call.  It may be several of them, because the
+            # deadlock avoidance mechanism is conservative.
+            nb_deadlocks = results.count((True, False))
+            self.assertGreaterEqual(nb_deadlocks, 1)
+            self.assertEqual(results.count((True, True)), len(results) - nb_deadlocks)
+
+        def test_no_deadlock(self):
+            results = self.run_deadlock_avoidance_test(False)
+            self.assertEqual(results.count((True, False)), 0)
+            self.assertEqual(results.count((True, True)), len(results))
+
+
+    DEADLOCK_ERRORS = {kind: splitinit._bootstrap._DeadlockError
+                       for kind, splitinit in init.items()}
+
+    (Frozen_DeadlockAvoidanceTests,
+     Source_DeadlockAvoidanceTests
+     ) = test_util.test_both(DeadlockAvoidanceTests,
+                             LockType=LOCK_TYPES,
+                             DeadlockError=DEADLOCK_ERRORS)
+else:
+    DEADLOCK_ERRORS = {}
+
+    class Frozen_DeadlockAvoidanceTests(unittest.TestCase):
+        pass
+
+    class Source_DeadlockAvoidanceTests(unittest.TestCase):
+        pass
+
+
+class LifetimeTests:
+
+    @property
+    def bootstrap(self):
+        return self.init._bootstrap
+
+    def test_lock_lifetime(self):
+        name = "xyzzy"
+        self.assertNotIn(name, self.bootstrap._module_locks)
+        lock = self.bootstrap._get_module_lock(name)
+        self.assertIn(name, self.bootstrap._module_locks)
+        wr = weakref.ref(lock)
+        del lock
+        support.gc_collect()
+        self.assertNotIn(name, self.bootstrap._module_locks)
+        self.assertIsNone(wr())
+
+    def test_all_locks(self):
+        support.gc_collect()
+        self.assertEqual(0, len(self.bootstrap._module_locks),
+                         self.bootstrap._module_locks)
+
+
+(Frozen_LifetimeTests,
+ Source_LifetimeTests
+ ) = test_util.test_both(LifetimeTests, init=init)
+
+
+@support.reap_threads
+def test_main():
+    support.run_unittest(Frozen_ModuleLockAsRLockTests,
+                         Source_ModuleLockAsRLockTests,
+                         Frozen_DeadlockAvoidanceTests,
+                         Source_DeadlockAvoidanceTests,
+                         Frozen_LifetimeTests,
+                         Source_LifetimeTests)
+
+
+if __name__ == '__main__':
+    test_main()

third_party/python/Lib/test/test_importlib/test_namespace_pkgs.py

@@ -0,0 +1,321 @@
+import contextlib
+import importlib
+import os
+import sys
+import unittest
+
+from test.test_importlib import util
+
+# needed tests:
+#
+# need to test when nested, so that the top-level path isn't sys.path
+# need to test dynamic path detection, both at top-level and nested
+# with dynamic path, check when a loader is returned on path reload (that is,
+#  trying to switch from a namespace package to a regular package)
+
+
+@contextlib.contextmanager
+def sys_modules_context():
+    """
+    Make sure sys.modules is the same object and has the same content
+    when exiting the context as when entering.
+
+    Similar to importlib.test.util.uncache, but doesn't require explicit
+    names.
+    """
+    sys_modules_saved = sys.modules
+    sys_modules_copy = sys.modules.copy()
+    try:
+        yield
+    finally:
+        sys.modules = sys_modules_saved
+        sys.modules.clear()
+        sys.modules.update(sys_modules_copy)
+
+
+@contextlib.contextmanager
+def namespace_tree_context(**kwargs):
+    """
+    Save import state and sys.modules cache and restore it on exit.
+    Typical usage:
+
+    >>> with namespace_tree_context(path=['/tmp/xxyy/portion1',
+    ...         '/tmp/xxyy/portion2']):
+    ...     pass
+    """
+    # use default meta_path and path_hooks unless specified otherwise
+    kwargs.setdefault('meta_path', sys.meta_path)
+    kwargs.setdefault('path_hooks', sys.path_hooks)
+    import_context = util.import_state(**kwargs)
+    with import_context, sys_modules_context():
+        yield
+
+class NamespacePackageTest(unittest.TestCase):
+    """
+    Subclasses should define self.root and self.paths (under that root)
+    to be added to sys.path.
+    """
+    root = os.path.join(os.path.dirname(__file__), 'namespace_pkgs')
+
+    def setUp(self):
+        self.resolved_paths = [
+            os.path.join(self.root, path) for path in self.paths
+        ]
+        self.ctx = namespace_tree_context(path=self.resolved_paths)
+        self.ctx.__enter__()
+
+    def tearDown(self):
+        # TODO: will we ever want to pass exc_info to __exit__?
+        self.ctx.__exit__(None, None, None)
+
+
+class SingleNamespacePackage(NamespacePackageTest):
+    paths = ['portion1']
+
+    def test_simple_package(self):
+        import foo.one
+        self.assertEqual(foo.one.attr, 'portion1 foo one')
+
+    def test_cant_import_other(self):
+        with self.assertRaises(ImportError):
+            import foo.two
+
+    def test_module_repr(self):
+        import foo.one
+        self.assertEqual(repr(foo), "<module 'foo' (namespace)>")
+
+
+class DynamicPathNamespacePackage(NamespacePackageTest):
+    paths = ['portion1']
+
+    def test_dynamic_path(self):
+        # Make sure only 'foo.one' can be imported
+        import foo.one
+        self.assertEqual(foo.one.attr, 'portion1 foo one')
+
+        with self.assertRaises(ImportError):
+            import foo.two
+
+        # Now modify sys.path
+        sys.path.append(os.path.join(self.root, 'portion2'))
+
+        # And make sure foo.two is now importable
+        import foo.two
+        self.assertEqual(foo.two.attr, 'portion2 foo two')
+
+
+class CombinedNamespacePackages(NamespacePackageTest):
+    paths = ['both_portions']
+
+    def test_imports(self):
+        import foo.one
+        import foo.two
+        self.assertEqual(foo.one.attr, 'both_portions foo one')
+        self.assertEqual(foo.two.attr, 'both_portions foo two')
+
+
+class SeparatedNamespacePackages(NamespacePackageTest):
+    paths = ['portion1', 'portion2']
+
+    def test_imports(self):
+        import foo.one
+        import foo.two
+        self.assertEqual(foo.one.attr, 'portion1 foo one')
+        self.assertEqual(foo.two.attr, 'portion2 foo two')
+
+
+class SeparatedOverlappingNamespacePackages(NamespacePackageTest):
+    paths = ['portion1', 'both_portions']
+
+    def test_first_path_wins(self):
+        import foo.one
+        import foo.two
+        self.assertEqual(foo.one.attr, 'portion1 foo one')
+        self.assertEqual(foo.two.attr, 'both_portions foo two')
+
+    def test_first_path_wins_again(self):
+        sys.path.reverse()
+        import foo.one
+        import foo.two
+        self.assertEqual(foo.one.attr, 'both_portions foo one')
+        self.assertEqual(foo.two.attr, 'both_portions foo two')
+
+    def test_first_path_wins_importing_second_first(self):
+        import foo.two
+        import foo.one
+        self.assertEqual(foo.one.attr, 'portion1 foo one')
+        self.assertEqual(foo.two.attr, 'both_portions foo two')
+
+
+class SingleZipNamespacePackage(NamespacePackageTest):
+    paths = ['top_level_portion1.zip']
+
+    def test_simple_package(self):
+        import foo.one
+        self.assertEqual(foo.one.attr, 'portion1 foo one')
+
+    def test_cant_import_other(self):
+        with self.assertRaises(ImportError):
+            import foo.two
+
+
+class SeparatedZipNamespacePackages(NamespacePackageTest):
+    paths = ['top_level_portion1.zip', 'portion2']
+
+    def test_imports(self):
+        import foo.one
+        import foo.two
+        self.assertEqual(foo.one.attr, 'portion1 foo one')
+        self.assertEqual(foo.two.attr, 'portion2 foo two')
+        self.assertIn('top_level_portion1.zip', foo.one.__file__)
+        self.assertNotIn('.zip', foo.two.__file__)
+
+
+class SingleNestedZipNamespacePackage(NamespacePackageTest):
+    paths = ['nested_portion1.zip/nested_portion1']
+
+    def test_simple_package(self):
+        import foo.one
+        self.assertEqual(foo.one.attr, 'portion1 foo one')
+
+    def test_cant_import_other(self):
+        with self.assertRaises(ImportError):
+            import foo.two
+
+
+class SeparatedNestedZipNamespacePackages(NamespacePackageTest):
+    paths = ['nested_portion1.zip/nested_portion1', 'portion2']
+
+    def test_imports(self):
+        import foo.one
+        import foo.two
+        self.assertEqual(foo.one.attr, 'portion1 foo one')
+        self.assertEqual(foo.two.attr, 'portion2 foo two')
+        fn = os.path.join('nested_portion1.zip', 'nested_portion1')
+        self.assertIn(fn, foo.one.__file__)
+        self.assertNotIn('.zip', foo.two.__file__)
+
+
+class LegacySupport(NamespacePackageTest):
+    paths = ['not_a_namespace_pkg', 'portion1', 'portion2', 'both_portions']
+
+    def test_non_namespace_package_takes_precedence(self):
+        import foo.one
+        with self.assertRaises(ImportError):
+            import foo.two
+        self.assertIn('__init__', foo.__file__)
+        self.assertNotIn('namespace', str(foo.__loader__).lower())
+
+
+class DynamicPathCalculation(NamespacePackageTest):
+    paths = ['project1', 'project2']
+
+    def test_project3_fails(self):
+        import parent.child.one
+        self.assertEqual(len(parent.__path__), 2)
+        self.assertEqual(len(parent.child.__path__), 2)
+        import parent.child.two
+        self.assertEqual(len(parent.__path__), 2)
+        self.assertEqual(len(parent.child.__path__), 2)
+
+        self.assertEqual(parent.child.one.attr, 'parent child one')
+        self.assertEqual(parent.child.two.attr, 'parent child two')
+
+        with self.assertRaises(ImportError):
+            import parent.child.three
+
+        self.assertEqual(len(parent.__path__), 2)
+        self.assertEqual(len(parent.child.__path__), 2)
+
+    def test_project3_succeeds(self):
+        import parent.child.one
+        self.assertEqual(len(parent.__path__), 2)
+        self.assertEqual(len(parent.child.__path__), 2)
+        import parent.child.two
+        self.assertEqual(len(parent.__path__), 2)
+        self.assertEqual(len(parent.child.__path__), 2)
+
+        self.assertEqual(parent.child.one.attr, 'parent child one')
+        self.assertEqual(parent.child.two.attr, 'parent child two')
+
+        with self.assertRaises(ImportError):
+            import parent.child.three
+
+        # now add project3
+        sys.path.append(os.path.join(self.root, 'project3'))
+        import parent.child.three
+
+        # the paths dynamically get longer, to include the new directories
+        self.assertEqual(len(parent.__path__), 3)
+        self.assertEqual(len(parent.child.__path__), 3)
+
+        self.assertEqual(parent.child.three.attr, 'parent child three')
+
+
+class ZipWithMissingDirectory(NamespacePackageTest):
+    paths = ['missing_directory.zip']
+
+    @unittest.expectedFailure
+    def test_missing_directory(self):
+        # This will fail because missing_directory.zip contains:
+        #   Length      Date    Time    Name
+        # ---------  ---------- -----   ----
+        #        29  2012-05-03 18:13   foo/one.py
+        #         0  2012-05-03 20:57   bar/
+        #        38  2012-05-03 20:57   bar/two.py
+        # ---------                     -------
+        #        67                     3 files
+
+        # Because there is no 'foo/', the zipimporter currently doesn't
+        #  know that foo is a namespace package
+
+        import foo.one
+
+    def test_present_directory(self):
+        # This succeeds because there is a "bar/" in the zip file
+        import bar.two
+        self.assertEqual(bar.two.attr, 'missing_directory foo two')
+
+
+class ModuleAndNamespacePackageInSameDir(NamespacePackageTest):
+    paths = ['module_and_namespace_package']
+
+    def test_module_before_namespace_package(self):
+        # Make sure we find the module in preference to the
+        #  namespace package.
+        import a_test
+        self.assertEqual(a_test.attr, 'in module')
+
+
+class ReloadTests(NamespacePackageTest):
+    paths = ['portion1']
+
+    def test_simple_package(self):
+        import foo.one
+        foo = importlib.reload(foo)
+        self.assertEqual(foo.one.attr, 'portion1 foo one')
+
+    def test_cant_import_other(self):
+        import foo
+        with self.assertRaises(ImportError):
+            import foo.two
+        foo = importlib.reload(foo)
+        with self.assertRaises(ImportError):
+            import foo.two
+
+    def test_dynamic_path(self):
+        import foo.one
+        with self.assertRaises(ImportError):
+            import foo.two
+
+        # Now modify sys.path and reload.
+        sys.path.append(os.path.join(self.root, 'portion2'))
+        foo = importlib.reload(foo)
+
+        # And make sure foo.two is now importable
+        import foo.two
+        self.assertEqual(foo.two.attr, 'portion2 foo two')
+
+
+if __name__ == "__main__":
+    unittest.main()

third_party/python/Lib/test/test_importlib/test_spec.py

@@ -0,0 +1,819 @@
+from . import util as test_util
+
+init = test_util.import_importlib('importlib')
+machinery = test_util.import_importlib('importlib.machinery')
+util = test_util.import_importlib('importlib.util')
+
+import os.path
+import pathlib
+from test.support import CleanImport
+import unittest
+import sys
+import warnings
+
+
+
+class TestLoader:
+
+    def __init__(self, path=None, is_package=None):
+        self.path = path
+        self.package = is_package
+
+    def __repr__(self):
+        return '<TestLoader object>'
+
+    def __getattr__(self, name):
+        if name == 'get_filename' and self.path is not None:
+            return self._get_filename
+        if name == 'is_package':
+            return self._is_package
+        raise AttributeError(name)
+
+    def _get_filename(self, name):
+        return self.path
+
+    def _is_package(self, name):
+        return self.package
+
+    def create_module(self, spec):
+        return None
+
+
+class NewLoader(TestLoader):
+
+    EGGS = 1
+
+    def exec_module(self, module):
+        module.eggs = self.EGGS
+
+
+class LegacyLoader(TestLoader):
+
+    HAM = -1
+
+    with warnings.catch_warnings():
+        warnings.simplefilter("ignore", DeprecationWarning)
+
+        frozen_util = util['Frozen']
+
+        @frozen_util.module_for_loader
+        def load_module(self, module):
+            module.ham = self.HAM
+            return module
+
+
+class ModuleSpecTests:
+
+    def setUp(self):
+        self.name = 'spam'
+        self.path = 'spam.py'
+        self.cached = self.util.cache_from_source(self.path)
+        self.loader = TestLoader()
+        self.spec = self.machinery.ModuleSpec(self.name, self.loader)
+        self.loc_spec = self.machinery.ModuleSpec(self.name, self.loader,
+                                                  origin=self.path)
+        self.loc_spec._set_fileattr = True
+
+    def test_default(self):
+        spec = self.machinery.ModuleSpec(self.name, self.loader)
+
+        self.assertEqual(spec.name, self.name)
+        self.assertEqual(spec.loader, self.loader)
+        self.assertIs(spec.origin, None)
+        self.assertIs(spec.loader_state, None)
+        self.assertIs(spec.submodule_search_locations, None)
+        self.assertIs(spec.cached, None)
+        self.assertFalse(spec.has_location)
+
+    def test_default_no_loader(self):
+        spec = self.machinery.ModuleSpec(self.name, None)
+
+        self.assertEqual(spec.name, self.name)
+        self.assertIs(spec.loader, None)
+        self.assertIs(spec.origin, None)
+        self.assertIs(spec.loader_state, None)
+        self.assertIs(spec.submodule_search_locations, None)
+        self.assertIs(spec.cached, None)
+        self.assertFalse(spec.has_location)
+
+    def test_default_is_package_false(self):
+        spec = self.machinery.ModuleSpec(self.name, self.loader,
+                                         is_package=False)
+
+        self.assertEqual(spec.name, self.name)
+        self.assertEqual(spec.loader, self.loader)
+        self.assertIs(spec.origin, None)
+        self.assertIs(spec.loader_state, None)
+        self.assertIs(spec.submodule_search_locations, None)
+        self.assertIs(spec.cached, None)
+        self.assertFalse(spec.has_location)
+
+    def test_default_is_package_true(self):
+        spec = self.machinery.ModuleSpec(self.name, self.loader,
+                                         is_package=True)
+
+        self.assertEqual(spec.name, self.name)
+        self.assertEqual(spec.loader, self.loader)
+        self.assertIs(spec.origin, None)
+        self.assertIs(spec.loader_state, None)
+        self.assertEqual(spec.submodule_search_locations, [])
+        self.assertIs(spec.cached, None)
+        self.assertFalse(spec.has_location)
+
+    def test_has_location_setter(self):
+        spec = self.machinery.ModuleSpec(self.name, self.loader,
+                                         origin='somewhere')
+        self.assertFalse(spec.has_location)
+        spec.has_location = True
+        self.assertTrue(spec.has_location)
+
+    def test_equality(self):
+        other = type(sys.implementation)(name=self.name,
+                                         loader=self.loader,
+                                         origin=None,
+                                         submodule_search_locations=None,
+                                         has_location=False,
+                                         cached=None,
+                                         )
+
+        self.assertTrue(self.spec == other)
+
+    def test_equality_location(self):
+        other = type(sys.implementation)(name=self.name,
+                                         loader=self.loader,
+                                         origin=self.path,
+                                         submodule_search_locations=None,
+                                         has_location=True,
+                                         cached=self.cached,
+                                         )
+
+        self.assertEqual(self.loc_spec, other)
+
+    def test_inequality(self):
+        other = type(sys.implementation)(name='ham',
+                                         loader=self.loader,
+                                         origin=None,
+                                         submodule_search_locations=None,
+                                         has_location=False,
+                                         cached=None,
+                                         )
+
+        self.assertNotEqual(self.spec, other)
+
+    def test_inequality_incomplete(self):
+        other = type(sys.implementation)(name=self.name,
+                                         loader=self.loader,
+                                         )
+
+        self.assertNotEqual(self.spec, other)
+
+    def test_package(self):
+        spec = self.machinery.ModuleSpec('spam.eggs', self.loader)
+
+        self.assertEqual(spec.parent, 'spam')
+
+    def test_package_is_package(self):
+        spec = self.machinery.ModuleSpec('spam.eggs', self.loader,
+                                         is_package=True)
+
+        self.assertEqual(spec.parent, 'spam.eggs')
+
+    # cached
+
+    def test_cached_set(self):
+        before = self.spec.cached
+        self.spec.cached = 'there'
+        after = self.spec.cached
+
+        self.assertIs(before, None)
+        self.assertEqual(after, 'there')
+
+    def test_cached_no_origin(self):
+        spec = self.machinery.ModuleSpec(self.name, self.loader)
+
+        self.assertIs(spec.cached, None)
+
+    def test_cached_with_origin_not_location(self):
+        spec = self.machinery.ModuleSpec(self.name, self.loader,
+                                         origin=self.path)
+
+        self.assertIs(spec.cached, None)
+
+    def test_cached_source(self):
+        expected = self.util.cache_from_source(self.path)
+
+        self.assertEqual(self.loc_spec.cached, expected)
+
+    def test_cached_source_unknown_suffix(self):
+        self.loc_spec.origin = 'spam.spamspamspam'
+
+        self.assertIs(self.loc_spec.cached, None)
+
+    def test_cached_source_missing_cache_tag(self):
+        original = sys.implementation.cache_tag
+        sys.implementation.cache_tag = None
+        try:
+            cached = self.loc_spec.cached
+        finally:
+            sys.implementation.cache_tag = original
+
+        self.assertIs(cached, None)
+
+    def test_cached_sourceless(self):
+        self.loc_spec.origin = 'spam.pyc'
+
+        self.assertEqual(self.loc_spec.cached, 'spam.pyc')
+
+
+(Frozen_ModuleSpecTests,
+ Source_ModuleSpecTests
+ ) = test_util.test_both(ModuleSpecTests, util=util, machinery=machinery)
+
+
+class ModuleSpecMethodsTests:
+
+    @property
+    def bootstrap(self):
+        return self.init._bootstrap
+
+    def setUp(self):
+        self.name = 'spam'
+        self.path = 'spam.py'
+        self.cached = self.util.cache_from_source(self.path)
+        self.loader = TestLoader()
+        self.spec = self.machinery.ModuleSpec(self.name, self.loader)
+        self.loc_spec = self.machinery.ModuleSpec(self.name, self.loader,
+                                                  origin=self.path)
+        self.loc_spec._set_fileattr = True
+
+    # exec()
+
+    def test_exec(self):
+        self.spec.loader = NewLoader()
+        module = self.util.module_from_spec(self.spec)
+        sys.modules[self.name] = module
+        self.assertFalse(hasattr(module, 'eggs'))
+        self.bootstrap._exec(self.spec, module)
+
+        self.assertEqual(module.eggs, 1)
+
+    # load()
+
+    def test_load(self):
+        self.spec.loader = NewLoader()
+        with CleanImport(self.spec.name):
+            loaded = self.bootstrap._load(self.spec)
+            installed = sys.modules[self.spec.name]
+
+        self.assertEqual(loaded.eggs, 1)
+        self.assertIs(loaded, installed)
+
+    def test_load_replaced(self):
+        replacement = object()
+        class ReplacingLoader(TestLoader):
+            def exec_module(self, module):
+                sys.modules[module.__name__] = replacement
+        self.spec.loader = ReplacingLoader()
+        with CleanImport(self.spec.name):
+            loaded = self.bootstrap._load(self.spec)
+            installed = sys.modules[self.spec.name]
+
+        self.assertIs(loaded, replacement)
+        self.assertIs(installed, replacement)
+
+    def test_load_failed(self):
+        class FailedLoader(TestLoader):
+            def exec_module(self, module):
+                raise RuntimeError
+        self.spec.loader = FailedLoader()
+        with CleanImport(self.spec.name):
+            with self.assertRaises(RuntimeError):
+                loaded = self.bootstrap._load(self.spec)
+            self.assertNotIn(self.spec.name, sys.modules)
+
+    def test_load_failed_removed(self):
+        class FailedLoader(TestLoader):
+            def exec_module(self, module):
+                del sys.modules[module.__name__]
+                raise RuntimeError
+        self.spec.loader = FailedLoader()
+        with CleanImport(self.spec.name):
+            with self.assertRaises(RuntimeError):
+                loaded = self.bootstrap._load(self.spec)
+            self.assertNotIn(self.spec.name, sys.modules)
+
+    def test_load_legacy(self):
+        self.spec.loader = LegacyLoader()
+        with CleanImport(self.spec.name):
+            loaded = self.bootstrap._load(self.spec)
+
+        self.assertEqual(loaded.ham, -1)
+
+    def test_load_legacy_attributes(self):
+        self.spec.loader = LegacyLoader()
+        with CleanImport(self.spec.name):
+            loaded = self.bootstrap._load(self.spec)
+
+        self.assertIs(loaded.__loader__, self.spec.loader)
+        self.assertEqual(loaded.__package__, self.spec.parent)
+        self.assertIs(loaded.__spec__, self.spec)
+
+    def test_load_legacy_attributes_immutable(self):
+        module = object()
+        class ImmutableLoader(TestLoader):
+            def load_module(self, name):
+                sys.modules[name] = module
+                return module
+        self.spec.loader = ImmutableLoader()
+        with CleanImport(self.spec.name):
+            loaded = self.bootstrap._load(self.spec)
+
+            self.assertIs(sys.modules[self.spec.name], module)
+
+    # reload()
+
+    def test_reload(self):
+        self.spec.loader = NewLoader()
+        with CleanImport(self.spec.name):
+            loaded = self.bootstrap._load(self.spec)
+            reloaded = self.bootstrap._exec(self.spec, loaded)
+            installed = sys.modules[self.spec.name]
+
+        self.assertEqual(loaded.eggs, 1)
+        self.assertIs(reloaded, loaded)
+        self.assertIs(installed, loaded)
+
+    def test_reload_modified(self):
+        self.spec.loader = NewLoader()
+        with CleanImport(self.spec.name):
+            loaded = self.bootstrap._load(self.spec)
+            loaded.eggs = 2
+            reloaded = self.bootstrap._exec(self.spec, loaded)
+
+        self.assertEqual(loaded.eggs, 1)
+        self.assertIs(reloaded, loaded)
+
+    def test_reload_extra_attributes(self):
+        self.spec.loader = NewLoader()
+        with CleanImport(self.spec.name):
+            loaded = self.bootstrap._load(self.spec)
+            loaded.available = False
+            reloaded = self.bootstrap._exec(self.spec, loaded)
+
+        self.assertFalse(loaded.available)
+        self.assertIs(reloaded, loaded)
+
+    def test_reload_init_module_attrs(self):
+        self.spec.loader = NewLoader()
+        with CleanImport(self.spec.name):
+            loaded = self.bootstrap._load(self.spec)
+            loaded.__name__ = 'ham'
+            del loaded.__loader__
+            del loaded.__package__
+            del loaded.__spec__
+            self.bootstrap._exec(self.spec, loaded)
+
+        self.assertEqual(loaded.__name__, self.spec.name)
+        self.assertIs(loaded.__loader__, self.spec.loader)
+        self.assertEqual(loaded.__package__, self.spec.parent)
+        self.assertIs(loaded.__spec__, self.spec)
+        self.assertFalse(hasattr(loaded, '__path__'))
+        self.assertFalse(hasattr(loaded, '__file__'))
+        self.assertFalse(hasattr(loaded, '__cached__'))
+
+    def test_reload_legacy(self):
+        self.spec.loader = LegacyLoader()
+        with CleanImport(self.spec.name):
+            loaded = self.bootstrap._load(self.spec)
+            reloaded = self.bootstrap._exec(self.spec, loaded)
+            installed = sys.modules[self.spec.name]
+
+        self.assertEqual(loaded.ham, -1)
+        self.assertIs(reloaded, loaded)
+        self.assertIs(installed, loaded)
+
+
+(Frozen_ModuleSpecMethodsTests,
+ Source_ModuleSpecMethodsTests
+ ) = test_util.test_both(ModuleSpecMethodsTests, init=init, util=util,
+                         machinery=machinery)
+
+
+class ModuleReprTests:
+
+    @property
+    def bootstrap(self):
+        return self.init._bootstrap
+
+    def setUp(self):
+        self.module = type(os)('spam')
+        self.spec = self.machinery.ModuleSpec('spam', TestLoader())
+
+    def test_module___loader___module_repr(self):
+        class Loader:
+            def module_repr(self, module):
+                return '<delicious {}>'.format(module.__name__)
+        self.module.__loader__ = Loader()
+        modrepr = self.bootstrap._module_repr(self.module)
+
+        self.assertEqual(modrepr, '<delicious spam>')
+
+    def test_module___loader___module_repr_bad(self):
+        class Loader(TestLoader):
+            def module_repr(self, module):
+                raise Exception
+        self.module.__loader__ = Loader()
+        modrepr = self.bootstrap._module_repr(self.module)
+
+        self.assertEqual(modrepr,
+                         '<module {!r} (<TestLoader object>)>'.format('spam'))
+
+    def test_module___spec__(self):
+        origin = 'in a hole, in the ground'
+        self.spec.origin = origin
+        self.module.__spec__ = self.spec
+        modrepr = self.bootstrap._module_repr(self.module)
+
+        self.assertEqual(modrepr, '<module {!r} ({})>'.format('spam', origin))
+
+    def test_module___spec___location(self):
+        location = 'in_a_galaxy_far_far_away.py'
+        self.spec.origin = location
+        self.spec._set_fileattr = True
+        self.module.__spec__ = self.spec
+        modrepr = self.bootstrap._module_repr(self.module)
+
+        self.assertEqual(modrepr,
+                         '<module {!r} from {!r}>'.format('spam', location))
+
+    def test_module___spec___no_origin(self):
+        self.spec.loader = TestLoader()
+        self.module.__spec__ = self.spec
+        modrepr = self.bootstrap._module_repr(self.module)
+
+        self.assertEqual(modrepr,
+                         '<module {!r} (<TestLoader object>)>'.format('spam'))
+
+    def test_module___spec___no_origin_no_loader(self):
+        self.spec.loader = None
+        self.module.__spec__ = self.spec
+        modrepr = self.bootstrap._module_repr(self.module)
+
+        self.assertEqual(modrepr, '<module {!r}>'.format('spam'))
+
+    def test_module_no_name(self):
+        del self.module.__name__
+        modrepr = self.bootstrap._module_repr(self.module)
+
+        self.assertEqual(modrepr, '<module {!r}>'.format('?'))
+
+    def test_module_with_file(self):
+        filename = 'e/i/e/i/o/spam.py'
+        self.module.__file__ = filename
+        modrepr = self.bootstrap._module_repr(self.module)
+
+        self.assertEqual(modrepr,
+                         '<module {!r} from {!r}>'.format('spam', filename))
+
+    def test_module_no_file(self):
+        self.module.__loader__ = TestLoader()
+        modrepr = self.bootstrap._module_repr(self.module)
+
+        self.assertEqual(modrepr,
+                         '<module {!r} (<TestLoader object>)>'.format('spam'))
+
+    def test_module_no_file_no_loader(self):
+        modrepr = self.bootstrap._module_repr(self.module)
+
+        self.assertEqual(modrepr, '<module {!r}>'.format('spam'))
+
+
+(Frozen_ModuleReprTests,
+ Source_ModuleReprTests
+ ) = test_util.test_both(ModuleReprTests, init=init, util=util,
+                         machinery=machinery)
+
+
+class FactoryTests:
+
+    def setUp(self):
+        self.name = 'spam'
+        self.path = 'spam.py'
+        self.cached = self.util.cache_from_source(self.path)
+        self.loader = TestLoader()
+        self.fileloader = TestLoader(self.path)
+        self.pkgloader = TestLoader(self.path, True)
+
+    # spec_from_loader()
+
+    def test_spec_from_loader_default(self):
+        spec = self.util.spec_from_loader(self.name, self.loader)
+
+        self.assertEqual(spec.name, self.name)
+        self.assertEqual(spec.loader, self.loader)
+        self.assertIs(spec.origin, None)
+        self.assertIs(spec.loader_state, None)
+        self.assertIs(spec.submodule_search_locations, None)
+        self.assertIs(spec.cached, None)
+        self.assertFalse(spec.has_location)
+
+    def test_spec_from_loader_default_with_bad_is_package(self):
+        class Loader:
+            def is_package(self, name):
+                raise ImportError
+        loader = Loader()
+        spec = self.util.spec_from_loader(self.name, loader)
+
+        self.assertEqual(spec.name, self.name)
+        self.assertEqual(spec.loader, loader)
+        self.assertIs(spec.origin, None)
+        self.assertIs(spec.loader_state, None)
+        self.assertIs(spec.submodule_search_locations, None)
+        self.assertIs(spec.cached, None)
+        self.assertFalse(spec.has_location)
+
+    def test_spec_from_loader_origin(self):
+        origin = 'somewhere over the rainbow'
+        spec = self.util.spec_from_loader(self.name, self.loader,
+                                          origin=origin)
+
+        self.assertEqual(spec.name, self.name)
+        self.assertEqual(spec.loader, self.loader)
+        self.assertIs(spec.origin, origin)
+        self.assertIs(spec.loader_state, None)
+        self.assertIs(spec.submodule_search_locations, None)
+        self.assertIs(spec.cached, None)
+        self.assertFalse(spec.has_location)
+
+    def test_spec_from_loader_is_package_false(self):
+        spec = self.util.spec_from_loader(self.name, self.loader,
+                                          is_package=False)
+
+        self.assertEqual(spec.name, self.name)
+        self.assertEqual(spec.loader, self.loader)
+        self.assertIs(spec.origin, None)
+        self.assertIs(spec.loader_state, None)
+        self.assertIs(spec.submodule_search_locations, None)
+        self.assertIs(spec.cached, None)
+        self.assertFalse(spec.has_location)
+
+    def test_spec_from_loader_is_package_true(self):
+        spec = self.util.spec_from_loader(self.name, self.loader,
+                                          is_package=True)
+
+        self.assertEqual(spec.name, self.name)
+        self.assertEqual(spec.loader, self.loader)
+        self.assertIs(spec.origin, None)
+        self.assertIs(spec.loader_state, None)
+        self.assertEqual(spec.submodule_search_locations, [])
+        self.assertIs(spec.cached, None)
+        self.assertFalse(spec.has_location)
+
+    def test_spec_from_loader_origin_and_is_package(self):
+        origin = 'where the streets have no name'
+        spec = self.util.spec_from_loader(self.name, self.loader,
+                                          origin=origin, is_package=True)
+
+        self.assertEqual(spec.name, self.name)
+        self.assertEqual(spec.loader, self.loader)
+        self.assertIs(spec.origin, origin)
+        self.assertIs(spec.loader_state, None)
+        self.assertEqual(spec.submodule_search_locations, [])
+        self.assertIs(spec.cached, None)
+        self.assertFalse(spec.has_location)
+
+    def test_spec_from_loader_is_package_with_loader_false(self):
+        loader = TestLoader(is_package=False)
+        spec = self.util.spec_from_loader(self.name, loader)
+
+        self.assertEqual(spec.name, self.name)
+        self.assertEqual(spec.loader, loader)
+        self.assertIs(spec.origin, None)
+        self.assertIs(spec.loader_state, None)
+        self.assertIs(spec.submodule_search_locations, None)
+        self.assertIs(spec.cached, None)
+        self.assertFalse(spec.has_location)
+
+    def test_spec_from_loader_is_package_with_loader_true(self):
+        loader = TestLoader(is_package=True)
+        spec = self.util.spec_from_loader(self.name, loader)
+
+        self.assertEqual(spec.name, self.name)
+        self.assertEqual(spec.loader, loader)
+        self.assertIs(spec.origin, None)
+        self.assertIs(spec.loader_state, None)
+        self.assertEqual(spec.submodule_search_locations, [])
+        self.assertIs(spec.cached, None)
+        self.assertFalse(spec.has_location)
+
+    def test_spec_from_loader_default_with_file_loader(self):
+        spec = self.util.spec_from_loader(self.name, self.fileloader)
+
+        self.assertEqual(spec.name, self.name)
+        self.assertEqual(spec.loader, self.fileloader)
+        self.assertEqual(spec.origin, self.path)
+        self.assertIs(spec.loader_state, None)
+        self.assertIs(spec.submodule_search_locations, None)
+        self.assertEqual(spec.cached, self.cached)
+        self.assertTrue(spec.has_location)
+
+    def test_spec_from_loader_is_package_false_with_fileloader(self):
+        spec = self.util.spec_from_loader(self.name, self.fileloader,
+                                          is_package=False)
+
+        self.assertEqual(spec.name, self.name)
+        self.assertEqual(spec.loader, self.fileloader)
+        self.assertEqual(spec.origin, self.path)
+        self.assertIs(spec.loader_state, None)
+        self.assertIs(spec.submodule_search_locations, None)
+        self.assertEqual(spec.cached, self.cached)
+        self.assertTrue(spec.has_location)
+
+    def test_spec_from_loader_is_package_true_with_fileloader(self):
+        spec = self.util.spec_from_loader(self.name, self.fileloader,
+                                          is_package=True)
+
+        self.assertEqual(spec.name, self.name)
+        self.assertEqual(spec.loader, self.fileloader)
+        self.assertEqual(spec.origin, self.path)
+        self.assertIs(spec.loader_state, None)
+        self.assertEqual(spec.submodule_search_locations, [''])
+        self.assertEqual(spec.cached, self.cached)
+        self.assertTrue(spec.has_location)
+
+    # spec_from_file_location()
+
+    def test_spec_from_file_location_default(self):
+        spec = self.util.spec_from_file_location(self.name, self.path)
+
+        self.assertEqual(spec.name, self.name)
+        # Need to use a circuitous route to get at importlib.machinery to make
+        # sure the same class object is used in the isinstance() check as
+        # would have been used to create the loader.
+        self.assertIsInstance(spec.loader,
+                              self.util.abc.machinery.SourceFileLoader)
+        self.assertEqual(spec.loader.name, self.name)
+        self.assertEqual(spec.loader.path, self.path)
+        self.assertEqual(spec.origin, self.path)
+        self.assertIs(spec.loader_state, None)
+        self.assertIs(spec.submodule_search_locations, None)
+        self.assertEqual(spec.cached, self.cached)
+        self.assertTrue(spec.has_location)
+
+    def test_spec_from_file_location_path_like_arg(self):
+        spec = self.util.spec_from_file_location(self.name,
+                                                 pathlib.PurePath(self.path))
+        self.assertEqual(spec.origin, self.path)
+
+    def test_spec_from_file_location_default_without_location(self):
+        spec = self.util.spec_from_file_location(self.name)
+
+        self.assertIs(spec, None)
+
+    def test_spec_from_file_location_default_bad_suffix(self):
+        spec = self.util.spec_from_file_location(self.name, 'spam.eggs')
+
+        self.assertIs(spec, None)
+
+    def test_spec_from_file_location_loader_no_location(self):
+        spec = self.util.spec_from_file_location(self.name,
+                                                 loader=self.fileloader)
+
+        self.assertEqual(spec.name, self.name)
+        self.assertEqual(spec.loader, self.fileloader)
+        self.assertEqual(spec.origin, self.path)
+        self.assertIs(spec.loader_state, None)
+        self.assertIs(spec.submodule_search_locations, None)
+        self.assertEqual(spec.cached, self.cached)
+        self.assertTrue(spec.has_location)
+
+    def test_spec_from_file_location_loader_no_location_no_get_filename(self):
+        spec = self.util.spec_from_file_location(self.name,
+                                                 loader=self.loader)
+
+        self.assertEqual(spec.name, self.name)
+        self.assertEqual(spec.loader, self.loader)
+        self.assertEqual(spec.origin, '<unknown>')
+        self.assertIs(spec.loader_state, None)
+        self.assertIs(spec.submodule_search_locations, None)
+        self.assertIs(spec.cached, None)
+        self.assertTrue(spec.has_location)
+
+    def test_spec_from_file_location_loader_no_location_bad_get_filename(self):
+        class Loader:
+            def get_filename(self, name):
+                raise ImportError
+        loader = Loader()
+        spec = self.util.spec_from_file_location(self.name, loader=loader)
+
+        self.assertEqual(spec.name, self.name)
+        self.assertEqual(spec.loader, loader)
+        self.assertEqual(spec.origin, '<unknown>')
+        self.assertIs(spec.loader_state, None)
+        self.assertIs(spec.submodule_search_locations, None)
+        self.assertIs(spec.cached, None)
+        self.assertTrue(spec.has_location)
+
+    def test_spec_from_file_location_smsl_none(self):
+        spec = self.util.spec_from_file_location(self.name, self.path,
+                                       loader=self.fileloader,
+                                       submodule_search_locations=None)
+
+        self.assertEqual(spec.name, self.name)
+        self.assertEqual(spec.loader, self.fileloader)
+        self.assertEqual(spec.origin, self.path)
+        self.assertIs(spec.loader_state, None)
+        self.assertIs(spec.submodule_search_locations, None)
+        self.assertEqual(spec.cached, self.cached)
+        self.assertTrue(spec.has_location)
+
+    def test_spec_from_file_location_smsl_empty(self):
+        spec = self.util.spec_from_file_location(self.name, self.path,
+                                       loader=self.fileloader,
+                                       submodule_search_locations=[])
+
+        self.assertEqual(spec.name, self.name)
+        self.assertEqual(spec.loader, self.fileloader)
+        self.assertEqual(spec.origin, self.path)
+        self.assertIs(spec.loader_state, None)
+        self.assertEqual(spec.submodule_search_locations, [''])
+        self.assertEqual(spec.cached, self.cached)
+        self.assertTrue(spec.has_location)
+
+    def test_spec_from_file_location_smsl_not_empty(self):
+        spec = self.util.spec_from_file_location(self.name, self.path,
+                                       loader=self.fileloader,
+                                       submodule_search_locations=['eggs'])
+
+        self.assertEqual(spec.name, self.name)
+        self.assertEqual(spec.loader, self.fileloader)
+        self.assertEqual(spec.origin, self.path)
+        self.assertIs(spec.loader_state, None)
+        self.assertEqual(spec.submodule_search_locations, ['eggs'])
+        self.assertEqual(spec.cached, self.cached)
+        self.assertTrue(spec.has_location)
+
+    def test_spec_from_file_location_smsl_default(self):
+        spec = self.util.spec_from_file_location(self.name, self.path,
+                                       loader=self.pkgloader)
+
+        self.assertEqual(spec.name, self.name)
+        self.assertEqual(spec.loader, self.pkgloader)
+        self.assertEqual(spec.origin, self.path)
+        self.assertIs(spec.loader_state, None)
+        self.assertEqual(spec.submodule_search_locations, [''])
+        self.assertEqual(spec.cached, self.cached)
+        self.assertTrue(spec.has_location)
+
+    def test_spec_from_file_location_smsl_default_not_package(self):
+        class Loader:
+            def is_package(self, name):
+                return False
+        loader = Loader()
+        spec = self.util.spec_from_file_location(self.name, self.path,
+                                                 loader=loader)
+
+        self.assertEqual(spec.name, self.name)
+        self.assertEqual(spec.loader, loader)
+        self.assertEqual(spec.origin, self.path)
+        self.assertIs(spec.loader_state, None)
+        self.assertIs(spec.submodule_search_locations, None)
+        self.assertEqual(spec.cached, self.cached)
+        self.assertTrue(spec.has_location)
+
+    def test_spec_from_file_location_smsl_default_no_is_package(self):
+        spec = self.util.spec_from_file_location(self.name, self.path,
+                                       loader=self.fileloader)
+
+        self.assertEqual(spec.name, self.name)
+        self.assertEqual(spec.loader, self.fileloader)
+        self.assertEqual(spec.origin, self.path)
+        self.assertIs(spec.loader_state, None)
+        self.assertIs(spec.submodule_search_locations, None)
+        self.assertEqual(spec.cached, self.cached)
+        self.assertTrue(spec.has_location)
+
+    def test_spec_from_file_location_smsl_default_bad_is_package(self):
+        class Loader:
+            def is_package(self, name):
+                raise ImportError
+        loader = Loader()
+        spec = self.util.spec_from_file_location(self.name, self.path,
+                                                 loader=loader)
+
+        self.assertEqual(spec.name, self.name)
+        self.assertEqual(spec.loader, loader)
+        self.assertEqual(spec.origin, self.path)
+        self.assertIs(spec.loader_state, None)
+        self.assertIs(spec.submodule_search_locations, None)
+        self.assertEqual(spec.cached, self.cached)
+        self.assertTrue(spec.has_location)
+
+
+(Frozen_FactoryTests,
+ Source_FactoryTests
+ ) = test_util.test_both(FactoryTests, util=util, machinery=machinery)
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/test_util.py

@@ -0,0 +1,805 @@
+from . import util
+abc = util.import_importlib('importlib.abc')
+init = util.import_importlib('importlib')
+machinery = util.import_importlib('importlib.machinery')
+importlib_util = util.import_importlib('importlib.util')
+
+import importlib.util
+import os
+import pathlib
+import string
+import sys
+from test import support
+import types
+import unittest
+import warnings
+
+
+class DecodeSourceBytesTests:
+
+    source = "string ='ü'"
+
+    def test_ut8_default(self):
+        source_bytes = self.source.encode('utf-8')
+        self.assertEqual(self.util.decode_source(source_bytes), self.source)
+
+    def test_specified_encoding(self):
+        source = '# coding=latin-1\n' + self.source
+        source_bytes = source.encode('latin-1')
+        assert source_bytes != source.encode('utf-8')
+        self.assertEqual(self.util.decode_source(source_bytes), source)
+
+    def test_universal_newlines(self):
+        source = '\r\n'.join([self.source, self.source])
+        source_bytes = source.encode('utf-8')
+        self.assertEqual(self.util.decode_source(source_bytes),
+                         '\n'.join([self.source, self.source]))
+
+
+(Frozen_DecodeSourceBytesTests,
+ Source_DecodeSourceBytesTests
+ ) = util.test_both(DecodeSourceBytesTests, util=importlib_util)
+
+
+class ModuleFromSpecTests:
+
+    def test_no_create_module(self):
+        class Loader:
+            def exec_module(self, module):
+                pass
+        spec = self.machinery.ModuleSpec('test', Loader())
+        with self.assertRaises(ImportError):
+            module = self.util.module_from_spec(spec)
+
+    def test_create_module_returns_None(self):
+        class Loader(self.abc.Loader):
+            def create_module(self, spec):
+                return None
+        spec = self.machinery.ModuleSpec('test', Loader())
+        module = self.util.module_from_spec(spec)
+        self.assertIsInstance(module, types.ModuleType)
+        self.assertEqual(module.__name__, spec.name)
+
+    def test_create_module(self):
+        name = 'already set'
+        class CustomModule(types.ModuleType):
+            pass
+        class Loader(self.abc.Loader):
+            def create_module(self, spec):
+                module = CustomModule(spec.name)
+                module.__name__ = name
+                return module
+        spec = self.machinery.ModuleSpec('test', Loader())
+        module = self.util.module_from_spec(spec)
+        self.assertIsInstance(module, CustomModule)
+        self.assertEqual(module.__name__, name)
+
+    def test___name__(self):
+        spec = self.machinery.ModuleSpec('test', object())
+        module = self.util.module_from_spec(spec)
+        self.assertEqual(module.__name__, spec.name)
+
+    def test___spec__(self):
+        spec = self.machinery.ModuleSpec('test', object())
+        module = self.util.module_from_spec(spec)
+        self.assertEqual(module.__spec__, spec)
+
+    def test___loader__(self):
+        loader = object()
+        spec = self.machinery.ModuleSpec('test', loader)
+        module = self.util.module_from_spec(spec)
+        self.assertIs(module.__loader__, loader)
+
+    def test___package__(self):
+        spec = self.machinery.ModuleSpec('test.pkg', object())
+        module = self.util.module_from_spec(spec)
+        self.assertEqual(module.__package__, spec.parent)
+
+    def test___path__(self):
+        spec = self.machinery.ModuleSpec('test', object(), is_package=True)
+        module = self.util.module_from_spec(spec)
+        self.assertEqual(module.__path__, spec.submodule_search_locations)
+
+    def test___file__(self):
+        spec = self.machinery.ModuleSpec('test', object(), origin='some/path')
+        spec.has_location = True
+        module = self.util.module_from_spec(spec)
+        self.assertEqual(module.__file__, spec.origin)
+
+    def test___cached__(self):
+        spec = self.machinery.ModuleSpec('test', object())
+        spec.cached = 'some/path'
+        spec.has_location = True
+        module = self.util.module_from_spec(spec)
+        self.assertEqual(module.__cached__, spec.cached)
+
+(Frozen_ModuleFromSpecTests,
+ Source_ModuleFromSpecTests
+) = util.test_both(ModuleFromSpecTests, abc=abc, machinery=machinery,
+                   util=importlib_util)
+
+
+class ModuleForLoaderTests:
+
+    """Tests for importlib.util.module_for_loader."""
+
+    @classmethod
+    def module_for_loader(cls, func):
+        with warnings.catch_warnings():
+            warnings.simplefilter('ignore', DeprecationWarning)
+            return cls.util.module_for_loader(func)
+
+    def test_warning(self):
+        # Should raise a PendingDeprecationWarning when used.
+        with warnings.catch_warnings():
+            warnings.simplefilter('error', DeprecationWarning)
+            with self.assertRaises(DeprecationWarning):
+                func = self.util.module_for_loader(lambda x: x)
+
+    def return_module(self, name):
+        fxn = self.module_for_loader(lambda self, module: module)
+        return fxn(self, name)
+
+    def raise_exception(self, name):
+        def to_wrap(self, module):
+            raise ImportError
+        fxn = self.module_for_loader(to_wrap)
+        try:
+            fxn(self, name)
+        except ImportError:
+            pass
+
+    def test_new_module(self):
+        # Test that when no module exists in sys.modules a new module is
+        # created.
+        module_name = 'a.b.c'
+        with util.uncache(module_name):
+            module = self.return_module(module_name)
+            self.assertIn(module_name, sys.modules)
+        self.assertIsInstance(module, types.ModuleType)
+        self.assertEqual(module.__name__, module_name)
+
+    def test_reload(self):
+        # Test that a module is reused if already in sys.modules.
+        class FakeLoader:
+            def is_package(self, name):
+                return True
+            @self.module_for_loader
+            def load_module(self, module):
+                return module
+        name = 'a.b.c'
+        module = types.ModuleType('a.b.c')
+        module.__loader__ = 42
+        module.__package__ = 42
+        with util.uncache(name):
+            sys.modules[name] = module
+            loader = FakeLoader()
+            returned_module = loader.load_module(name)
+            self.assertIs(returned_module, sys.modules[name])
+            self.assertEqual(module.__loader__, loader)
+            self.assertEqual(module.__package__, name)
+
+    def test_new_module_failure(self):
+        # Test that a module is removed from sys.modules if added but an
+        # exception is raised.
+        name = 'a.b.c'
+        with util.uncache(name):
+            self.raise_exception(name)
+            self.assertNotIn(name, sys.modules)
+
+    def test_reload_failure(self):
+        # Test that a failure on reload leaves the module in-place.
+        name = 'a.b.c'
+        module = types.ModuleType(name)
+        with util.uncache(name):
+            sys.modules[name] = module
+            self.raise_exception(name)
+            self.assertIs(module, sys.modules[name])
+
+    def test_decorator_attrs(self):
+        def fxn(self, module): pass
+        wrapped = self.module_for_loader(fxn)
+        self.assertEqual(wrapped.__name__, fxn.__name__)
+        self.assertEqual(wrapped.__qualname__, fxn.__qualname__)
+
+    def test_false_module(self):
+        # If for some odd reason a module is considered false, still return it
+        # from sys.modules.
+        class FalseModule(types.ModuleType):
+            def __bool__(self): return False
+
+        name = 'mod'
+        module = FalseModule(name)
+        with util.uncache(name):
+            self.assertFalse(module)
+            sys.modules[name] = module
+            given = self.return_module(name)
+            self.assertIs(given, module)
+
+    def test_attributes_set(self):
+        # __name__, __loader__, and __package__ should be set (when
+        # is_package() is defined; undefined implicitly tested elsewhere).
+        class FakeLoader:
+            def __init__(self, is_package):
+                self._pkg = is_package
+            def is_package(self, name):
+                return self._pkg
+            @self.module_for_loader
+            def load_module(self, module):
+                return module
+
+        name = 'pkg.mod'
+        with util.uncache(name):
+            loader = FakeLoader(False)
+            module = loader.load_module(name)
+            self.assertEqual(module.__name__, name)
+            self.assertIs(module.__loader__, loader)
+            self.assertEqual(module.__package__, 'pkg')
+
+        name = 'pkg.sub'
+        with util.uncache(name):
+            loader = FakeLoader(True)
+            module = loader.load_module(name)
+            self.assertEqual(module.__name__, name)
+            self.assertIs(module.__loader__, loader)
+            self.assertEqual(module.__package__, name)
+
+
+(Frozen_ModuleForLoaderTests,
+ Source_ModuleForLoaderTests
+ ) = util.test_both(ModuleForLoaderTests, util=importlib_util)
+
+
+class SetPackageTests:
+
+    """Tests for importlib.util.set_package."""
+
+    def verify(self, module, expect):
+        """Verify the module has the expected value for __package__ after
+        passing through set_package."""
+        fxn = lambda: module
+        wrapped = self.util.set_package(fxn)
+        with warnings.catch_warnings():
+            warnings.simplefilter('ignore', DeprecationWarning)
+            wrapped()
+        self.assertTrue(hasattr(module, '__package__'))
+        self.assertEqual(expect, module.__package__)
+
+    def test_top_level(self):
+        # __package__ should be set to the empty string if a top-level module.
+        # Implicitly tests when package is set to None.
+        module = types.ModuleType('module')
+        module.__package__ = None
+        self.verify(module, '')
+
+    def test_package(self):
+        # Test setting __package__ for a package.
+        module = types.ModuleType('pkg')
+        module.__path__ = ['<path>']
+        module.__package__ = None
+        self.verify(module, 'pkg')
+
+    def test_submodule(self):
+        # Test __package__ for a module in a package.
+        module = types.ModuleType('pkg.mod')
+        module.__package__ = None
+        self.verify(module, 'pkg')
+
+    def test_setting_if_missing(self):
+        # __package__ should be set if it is missing.
+        module = types.ModuleType('mod')
+        if hasattr(module, '__package__'):
+            delattr(module, '__package__')
+        self.verify(module, '')
+
+    def test_leaving_alone(self):
+        # If __package__ is set and not None then leave it alone.
+        for value in (True, False):
+            module = types.ModuleType('mod')
+            module.__package__ = value
+            self.verify(module, value)
+
+    def test_decorator_attrs(self):
+        def fxn(module): pass
+        with warnings.catch_warnings():
+            warnings.simplefilter('ignore', DeprecationWarning)
+            wrapped = self.util.set_package(fxn)
+        self.assertEqual(wrapped.__name__, fxn.__name__)
+        self.assertEqual(wrapped.__qualname__, fxn.__qualname__)
+
+
+(Frozen_SetPackageTests,
+ Source_SetPackageTests
+ ) = util.test_both(SetPackageTests, util=importlib_util)
+
+
+class SetLoaderTests:
+
+    """Tests importlib.util.set_loader()."""
+
+    @property
+    def DummyLoader(self):
+        # Set DummyLoader on the class lazily.
+        class DummyLoader:
+            @self.util.set_loader
+            def load_module(self, module):
+                return self.module
+        self.__class__.DummyLoader = DummyLoader
+        return DummyLoader
+
+    def test_no_attribute(self):
+        loader = self.DummyLoader()
+        loader.module = types.ModuleType('blah')
+        try:
+            del loader.module.__loader__
+        except AttributeError:
+            pass
+        with warnings.catch_warnings():
+            warnings.simplefilter('ignore', DeprecationWarning)
+            self.assertEqual(loader, loader.load_module('blah').__loader__)
+
+    def test_attribute_is_None(self):
+        loader = self.DummyLoader()
+        loader.module = types.ModuleType('blah')
+        loader.module.__loader__ = None
+        with warnings.catch_warnings():
+            warnings.simplefilter('ignore', DeprecationWarning)
+            self.assertEqual(loader, loader.load_module('blah').__loader__)
+
+    def test_not_reset(self):
+        loader = self.DummyLoader()
+        loader.module = types.ModuleType('blah')
+        loader.module.__loader__ = 42
+        with warnings.catch_warnings():
+            warnings.simplefilter('ignore', DeprecationWarning)
+            self.assertEqual(42, loader.load_module('blah').__loader__)
+
+
+(Frozen_SetLoaderTests,
+ Source_SetLoaderTests
+ ) = util.test_both(SetLoaderTests, util=importlib_util)
+
+
+class ResolveNameTests:
+
+    """Tests importlib.util.resolve_name()."""
+
+    def test_absolute(self):
+        # bacon
+        self.assertEqual('bacon', self.util.resolve_name('bacon', None))
+
+    def test_absolute_within_package(self):
+        # bacon in spam
+        self.assertEqual('bacon', self.util.resolve_name('bacon', 'spam'))
+
+    def test_no_package(self):
+        # .bacon in ''
+        with self.assertRaises(ValueError):
+            self.util.resolve_name('.bacon', '')
+
+    def test_in_package(self):
+        # .bacon in spam
+        self.assertEqual('spam.eggs.bacon',
+                         self.util.resolve_name('.bacon', 'spam.eggs'))
+
+    def test_other_package(self):
+        # ..bacon in spam.bacon
+        self.assertEqual('spam.bacon',
+                         self.util.resolve_name('..bacon', 'spam.eggs'))
+
+    def test_escape(self):
+        # ..bacon in spam
+        with self.assertRaises(ValueError):
+            self.util.resolve_name('..bacon', 'spam')
+
+
+(Frozen_ResolveNameTests,
+ Source_ResolveNameTests
+ ) = util.test_both(ResolveNameTests, util=importlib_util)
+
+
+class FindSpecTests:
+
+    class FakeMetaFinder:
+        @staticmethod
+        def find_spec(name, path=None, target=None): return name, path, target
+
+    def test_sys_modules(self):
+        name = 'some_mod'
+        with util.uncache(name):
+            module = types.ModuleType(name)
+            loader = 'a loader!'
+            spec = self.machinery.ModuleSpec(name, loader)
+            module.__loader__ = loader
+            module.__spec__ = spec
+            sys.modules[name] = module
+            found = self.util.find_spec(name)
+            self.assertEqual(found, spec)
+
+    def test_sys_modules_without___loader__(self):
+        name = 'some_mod'
+        with util.uncache(name):
+            module = types.ModuleType(name)
+            del module.__loader__
+            loader = 'a loader!'
+            spec = self.machinery.ModuleSpec(name, loader)
+            module.__spec__ = spec
+            sys.modules[name] = module
+            found = self.util.find_spec(name)
+            self.assertEqual(found, spec)
+
+    def test_sys_modules_spec_is_None(self):
+        name = 'some_mod'
+        with util.uncache(name):
+            module = types.ModuleType(name)
+            module.__spec__ = None
+            sys.modules[name] = module
+            with self.assertRaises(ValueError):
+                self.util.find_spec(name)
+
+    def test_sys_modules_loader_is_None(self):
+        name = 'some_mod'
+        with util.uncache(name):
+            module = types.ModuleType(name)
+            spec = self.machinery.ModuleSpec(name, None)
+            module.__spec__ = spec
+            sys.modules[name] = module
+            found = self.util.find_spec(name)
+            self.assertEqual(found, spec)
+
+    def test_sys_modules_spec_is_not_set(self):
+        name = 'some_mod'
+        with util.uncache(name):
+            module = types.ModuleType(name)
+            try:
+                del module.__spec__
+            except AttributeError:
+                pass
+            sys.modules[name] = module
+            with self.assertRaises(ValueError):
+                self.util.find_spec(name)
+
+    def test_success(self):
+        name = 'some_mod'
+        with util.uncache(name):
+            with util.import_state(meta_path=[self.FakeMetaFinder]):
+                self.assertEqual((name, None, None),
+                                 self.util.find_spec(name))
+
+    def test_nothing(self):
+        # None is returned upon failure to find a loader.
+        self.assertIsNone(self.util.find_spec('nevergoingtofindthismodule'))
+
+    def test_find_submodule(self):
+        name = 'spam'
+        subname = 'ham'
+        with util.temp_module(name, pkg=True) as pkg_dir:
+            fullname, _ = util.submodule(name, subname, pkg_dir)
+            spec = self.util.find_spec(fullname)
+            self.assertIsNot(spec, None)
+            self.assertIn(name, sorted(sys.modules))
+            self.assertNotIn(fullname, sorted(sys.modules))
+            # Ensure successive calls behave the same.
+            spec_again = self.util.find_spec(fullname)
+            self.assertEqual(spec_again, spec)
+
+    def test_find_submodule_parent_already_imported(self):
+        name = 'spam'
+        subname = 'ham'
+        with util.temp_module(name, pkg=True) as pkg_dir:
+            self.init.import_module(name)
+            fullname, _ = util.submodule(name, subname, pkg_dir)
+            spec = self.util.find_spec(fullname)
+            self.assertIsNot(spec, None)
+            self.assertIn(name, sorted(sys.modules))
+            self.assertNotIn(fullname, sorted(sys.modules))
+            # Ensure successive calls behave the same.
+            spec_again = self.util.find_spec(fullname)
+            self.assertEqual(spec_again, spec)
+
+    def test_find_relative_module(self):
+        name = 'spam'
+        subname = 'ham'
+        with util.temp_module(name, pkg=True) as pkg_dir:
+            fullname, _ = util.submodule(name, subname, pkg_dir)
+            relname = '.' + subname
+            spec = self.util.find_spec(relname, name)
+            self.assertIsNot(spec, None)
+            self.assertIn(name, sorted(sys.modules))
+            self.assertNotIn(fullname, sorted(sys.modules))
+            # Ensure successive calls behave the same.
+            spec_again = self.util.find_spec(fullname)
+            self.assertEqual(spec_again, spec)
+
+    def test_find_relative_module_missing_package(self):
+        name = 'spam'
+        subname = 'ham'
+        with util.temp_module(name, pkg=True) as pkg_dir:
+            fullname, _ = util.submodule(name, subname, pkg_dir)
+            relname = '.' + subname
+            with self.assertRaises(ValueError):
+                self.util.find_spec(relname)
+            self.assertNotIn(name, sorted(sys.modules))
+            self.assertNotIn(fullname, sorted(sys.modules))
+
+
+(Frozen_FindSpecTests,
+ Source_FindSpecTests
+ ) = util.test_both(FindSpecTests, init=init, util=importlib_util,
+                         machinery=machinery)
+
+
+class MagicNumberTests:
+
+    def test_length(self):
+        # Should be 4 bytes.
+        self.assertEqual(len(self.util.MAGIC_NUMBER), 4)
+
+    def test_incorporates_rn(self):
+        # The magic number uses \r\n to come out wrong when splitting on lines.
+        self.assertTrue(self.util.MAGIC_NUMBER.endswith(b'\r\n'))
+
+
+(Frozen_MagicNumberTests,
+ Source_MagicNumberTests
+ ) = util.test_both(MagicNumberTests, util=importlib_util)
+
+
+class PEP3147Tests:
+
+    """Tests of PEP 3147-related functions: cache_from_source and source_from_cache."""
+
+    tag = sys.implementation.cache_tag
+
+    @unittest.skipUnless(sys.implementation.cache_tag is not None,
+                         'requires sys.implementation.cache_tag not be None')
+    def test_cache_from_source(self):
+        # Given the path to a .py file, return the path to its PEP 3147
+        # defined .pyc file (i.e. under __pycache__).
+        path = os.path.join('foo', 'bar', 'baz', 'qux.py')
+        expect = os.path.join('foo', 'bar', 'baz', '__pycache__',
+                              'qux.{}.pyc'.format(self.tag))
+        self.assertEqual(self.util.cache_from_source(path, optimization=''),
+                         expect)
+
+    def test_cache_from_source_no_cache_tag(self):
+        # No cache tag means NotImplementedError.
+        with support.swap_attr(sys.implementation, 'cache_tag', None):
+            with self.assertRaises(NotImplementedError):
+                self.util.cache_from_source('whatever.py')
+
+    def test_cache_from_source_no_dot(self):
+        # Directory with a dot, filename without dot.
+        path = os.path.join('foo.bar', 'file')
+        expect = os.path.join('foo.bar', '__pycache__',
+                              'file{}.pyc'.format(self.tag))
+        self.assertEqual(self.util.cache_from_source(path, optimization=''),
+                         expect)
+
+    def test_cache_from_source_debug_override(self):
+        # Given the path to a .py file, return the path to its PEP 3147/PEP 488
+        # defined .pyc file (i.e. under __pycache__).
+        path = os.path.join('foo', 'bar', 'baz', 'qux.py')
+        with warnings.catch_warnings():
+            warnings.simplefilter('ignore')
+            self.assertEqual(self.util.cache_from_source(path, False),
+                             self.util.cache_from_source(path, optimization=1))
+            self.assertEqual(self.util.cache_from_source(path, True),
+                             self.util.cache_from_source(path, optimization=''))
+        with warnings.catch_warnings():
+            warnings.simplefilter('error')
+            with self.assertRaises(DeprecationWarning):
+                self.util.cache_from_source(path, False)
+            with self.assertRaises(DeprecationWarning):
+                self.util.cache_from_source(path, True)
+
+    def test_cache_from_source_cwd(self):
+        path = 'foo.py'
+        expect = os.path.join('__pycache__', 'foo.{}.pyc'.format(self.tag))
+        self.assertEqual(self.util.cache_from_source(path, optimization=''),
+                         expect)
+
+    def test_cache_from_source_override(self):
+        # When debug_override is not None, it can be any true-ish or false-ish
+        # value.
+        path = os.path.join('foo', 'bar', 'baz.py')
+        # However if the bool-ishness can't be determined, the exception
+        # propagates.
+        class Bearish:
+            def __bool__(self): raise RuntimeError
+        with warnings.catch_warnings():
+            warnings.simplefilter('ignore')
+            self.assertEqual(self.util.cache_from_source(path, []),
+                             self.util.cache_from_source(path, optimization=1))
+            self.assertEqual(self.util.cache_from_source(path, [17]),
+                             self.util.cache_from_source(path, optimization=''))
+            with self.assertRaises(RuntimeError):
+                self.util.cache_from_source('/foo/bar/baz.py', Bearish())
+
+
+    def test_cache_from_source_optimization_empty_string(self):
+        # Setting 'optimization' to '' leads to no optimization tag (PEP 488).
+        path = 'foo.py'
+        expect = os.path.join('__pycache__', 'foo.{}.pyc'.format(self.tag))
+        self.assertEqual(self.util.cache_from_source(path, optimization=''),
+                         expect)
+
+    def test_cache_from_source_optimization_None(self):
+        # Setting 'optimization' to None uses the interpreter's optimization.
+        # (PEP 488)
+        path = 'foo.py'
+        optimization_level = sys.flags.optimize
+        almost_expect = os.path.join('__pycache__', 'foo.{}'.format(self.tag))
+        if optimization_level == 0:
+            expect = almost_expect + '.pyc'
+        elif optimization_level <= 2:
+            expect = almost_expect + '.opt-{}.pyc'.format(optimization_level)
+        else:
+            msg = '{!r} is a non-standard optimization level'.format(optimization_level)
+            self.skipTest(msg)
+        self.assertEqual(self.util.cache_from_source(path, optimization=None),
+                         expect)
+
+    def test_cache_from_source_optimization_set(self):
+        # The 'optimization' parameter accepts anything that has a string repr
+        # that passes str.alnum().
+        path = 'foo.py'
+        valid_characters = string.ascii_letters + string.digits
+        almost_expect = os.path.join('__pycache__', 'foo.{}'.format(self.tag))
+        got = self.util.cache_from_source(path, optimization=valid_characters)
+        # Test all valid characters are accepted.
+        self.assertEqual(got,
+                         almost_expect + '.opt-{}.pyc'.format(valid_characters))
+        # str() should be called on argument.
+        self.assertEqual(self.util.cache_from_source(path, optimization=42),
+                         almost_expect + '.opt-42.pyc')
+        # Invalid characters raise ValueError.
+        with self.assertRaises(ValueError):
+            self.util.cache_from_source(path, optimization='path/is/bad')
+
+    def test_cache_from_source_debug_override_optimization_both_set(self):
+        # Can only set one of the optimization-related parameters.
+        with warnings.catch_warnings():
+            warnings.simplefilter('ignore')
+            with self.assertRaises(TypeError):
+                self.util.cache_from_source('foo.py', False, optimization='')
+
+    @unittest.skipUnless(os.sep == '\\' and os.altsep == '/',
+                     'test meaningful only where os.altsep is defined')
+    def test_sep_altsep_and_sep_cache_from_source(self):
+        # Windows path and PEP 3147 where sep is right of altsep.
+        self.assertEqual(
+            self.util.cache_from_source('\\foo\\bar\\baz/qux.py', optimization=''),
+            '\\foo\\bar\\baz\\__pycache__\\qux.{}.pyc'.format(self.tag))
+
+    @unittest.skipUnless(sys.implementation.cache_tag is not None,
+                         'requires sys.implementation.cache_tag not be None')
+    def test_source_from_cache_path_like_arg(self):
+        path = pathlib.PurePath('foo', 'bar', 'baz', 'qux.py')
+        expect = os.path.join('foo', 'bar', 'baz', '__pycache__',
+                              'qux.{}.pyc'.format(self.tag))
+        self.assertEqual(self.util.cache_from_source(path, optimization=''),
+                         expect)
+
+    @unittest.skipUnless(sys.implementation.cache_tag is not None,
+                         'requires sys.implementation.cache_tag to not be '
+                         'None')
+    def test_source_from_cache(self):
+        # Given the path to a PEP 3147 defined .pyc file, return the path to
+        # its source.  This tests the good path.
+        path = os.path.join('foo', 'bar', 'baz', '__pycache__',
+                            'qux.{}.pyc'.format(self.tag))
+        expect = os.path.join('foo', 'bar', 'baz', 'qux.py')
+        self.assertEqual(self.util.source_from_cache(path), expect)
+
+    def test_source_from_cache_no_cache_tag(self):
+        # If sys.implementation.cache_tag is None, raise NotImplementedError.
+        path = os.path.join('blah', '__pycache__', 'whatever.pyc')
+        with support.swap_attr(sys.implementation, 'cache_tag', None):
+            with self.assertRaises(NotImplementedError):
+                self.util.source_from_cache(path)
+
+    def test_source_from_cache_bad_path(self):
+        # When the path to a pyc file is not in PEP 3147 format, a ValueError
+        # is raised.
+        self.assertRaises(
+            ValueError, self.util.source_from_cache, '/foo/bar/bazqux.pyc')
+
+    def test_source_from_cache_no_slash(self):
+        # No slashes at all in path -> ValueError
+        self.assertRaises(
+            ValueError, self.util.source_from_cache, 'foo.cpython-32.pyc')
+
+    def test_source_from_cache_too_few_dots(self):
+        # Too few dots in final path component -> ValueError
+        self.assertRaises(
+            ValueError, self.util.source_from_cache, '__pycache__/foo.pyc')
+
+    def test_source_from_cache_too_many_dots(self):
+        with self.assertRaises(ValueError):
+            self.util.source_from_cache(
+                    '__pycache__/foo.cpython-32.opt-1.foo.pyc')
+
+    def test_source_from_cache_not_opt(self):
+        # Non-`opt-` path component -> ValueError
+        self.assertRaises(
+            ValueError, self.util.source_from_cache,
+            '__pycache__/foo.cpython-32.foo.pyc')
+
+    def test_source_from_cache_no__pycache__(self):
+        # Another problem with the path -> ValueError
+        self.assertRaises(
+            ValueError, self.util.source_from_cache,
+            '/foo/bar/foo.cpython-32.foo.pyc')
+
+    def test_source_from_cache_optimized_bytecode(self):
+        # Optimized bytecode is not an issue.
+        path = os.path.join('__pycache__', 'foo.{}.opt-1.pyc'.format(self.tag))
+        self.assertEqual(self.util.source_from_cache(path), 'foo.py')
+
+    def test_source_from_cache_missing_optimization(self):
+        # An empty optimization level is a no-no.
+        path = os.path.join('__pycache__', 'foo.{}.opt-.pyc'.format(self.tag))
+        with self.assertRaises(ValueError):
+            self.util.source_from_cache(path)
+
+    @unittest.skipUnless(sys.implementation.cache_tag is not None,
+                         'requires sys.implementation.cache_tag to not be '
+                         'None')
+    def test_source_from_cache_path_like_arg(self):
+        path = pathlib.PurePath('foo', 'bar', 'baz', '__pycache__',
+                                'qux.{}.pyc'.format(self.tag))
+        expect = os.path.join('foo', 'bar', 'baz', 'qux.py')
+        self.assertEqual(self.util.source_from_cache(path), expect)
+
+
+(Frozen_PEP3147Tests,
+ Source_PEP3147Tests
+ ) = util.test_both(PEP3147Tests, util=importlib_util)
+
+
+class MagicNumberTests(unittest.TestCase):
+    """
+    Test release compatibility issues relating to importlib
+    """
+    @unittest.skipUnless(
+        sys.version_info.releaselevel in ('candidate', 'final'),
+        'only applies to candidate or final python release levels'
+    )
+    def test_magic_number(self):
+        """
+        Each python minor release should generally have a MAGIC_NUMBER
+        that does not change once the release reaches candidate status.
+
+        Once a release reaches candidate status, the value of the constant
+        EXPECTED_MAGIC_NUMBER in this test should be changed.
+        This test will then check that the actual MAGIC_NUMBER matches
+        the expected value for the release.
+
+        In exceptional cases, it may be required to change the MAGIC_NUMBER
+        for a maintenance release. In this case the change should be
+        discussed in python-dev. If a change is required, community
+        stakeholders such as OS package maintainers must be notified
+        in advance. Such exceptional releases will then require an
+        adjustment to this test case.
+        """
+        EXPECTED_MAGIC_NUMBER = 3379
+        actual = int.from_bytes(importlib.util.MAGIC_NUMBER[:2], 'little')
+
+        msg = (
+            "To avoid breaking backwards compatibility with cached bytecode "
+            "files that can't be automatically regenerated by the current "
+            "user, candidate and final releases require the current  "
+            "importlib.util.MAGIC_NUMBER to match the expected "
+            "magic number in this test. Set the expected "
+            "magic number in this test to the current MAGIC_NUMBER to "
+            "continue with the release.\n\n"
+            "Changing the MAGIC_NUMBER for a maintenance release "
+            "requires discussion in python-dev and notification of "
+            "community stakeholders."
+        )
+        self.assertEqual(EXPECTED_MAGIC_NUMBER, actual, msg)
+
+
+if __name__ == '__main__':
+    unittest.main()

third_party/python/Lib/test/test_importlib/test_windows.py

@@ -0,0 +1,109 @@
+from . import util as test_util
+machinery = test_util.import_importlib('importlib.machinery')
+
+import os
+import re
+import sys
+import unittest
+from test import support
+from distutils.util import get_platform
+from contextlib import contextmanager
+from .util import temp_module
+
+support.import_module('winreg', required_on=['win'])
+from winreg import (
+    CreateKey, HKEY_CURRENT_USER,
+    SetValue, REG_SZ, KEY_ALL_ACCESS,
+    EnumKey, CloseKey, DeleteKey, OpenKey
+)
+
+def delete_registry_tree(root, subkey):
+    try:
+        hkey = OpenKey(root, subkey, access=KEY_ALL_ACCESS)
+    except OSError:
+        # subkey does not exist
+        return
+    while True:
+        try:
+            subsubkey = EnumKey(hkey, 0)
+        except OSError:
+            # no more subkeys
+            break
+        delete_registry_tree(hkey, subsubkey)
+    CloseKey(hkey)
+    DeleteKey(root, subkey)
+
+@contextmanager
+def setup_module(machinery, name, path=None):
+    if machinery.WindowsRegistryFinder.DEBUG_BUILD:
+        root = machinery.WindowsRegistryFinder.REGISTRY_KEY_DEBUG
+    else:
+        root = machinery.WindowsRegistryFinder.REGISTRY_KEY
+    key = root.format(fullname=name,
+                      sys_version='%d.%d' % sys.version_info[:2])
+    try:
+        with temp_module(name, "a = 1") as location:
+            subkey = CreateKey(HKEY_CURRENT_USER, key)
+            if path is None:
+                path = location + ".py"
+            SetValue(subkey, "", REG_SZ, path)
+            yield
+    finally:
+        if machinery.WindowsRegistryFinder.DEBUG_BUILD:
+            key = os.path.dirname(key)
+        delete_registry_tree(HKEY_CURRENT_USER, key)
+
+
+@unittest.skipUnless(sys.platform.startswith('win'), 'requires Windows')
+class WindowsRegistryFinderTests:
+    # The module name is process-specific, allowing for
+    # simultaneous runs of the same test on a single machine.
+    test_module = "spamham{}".format(os.getpid())
+
+    def test_find_spec_missing(self):
+        spec = self.machinery.WindowsRegistryFinder.find_spec('spam')
+        self.assertIs(spec, None)
+
+    def test_find_module_missing(self):
+        loader = self.machinery.WindowsRegistryFinder.find_module('spam')
+        self.assertIs(loader, None)
+
+    def test_module_found(self):
+        with setup_module(self.machinery, self.test_module):
+            loader = self.machinery.WindowsRegistryFinder.find_module(self.test_module)
+            spec = self.machinery.WindowsRegistryFinder.find_spec(self.test_module)
+            self.assertIsNot(loader, None)
+            self.assertIsNot(spec, None)
+
+    def test_module_not_found(self):
+        with setup_module(self.machinery, self.test_module, path="."):
+            loader = self.machinery.WindowsRegistryFinder.find_module(self.test_module)
+            spec = self.machinery.WindowsRegistryFinder.find_spec(self.test_module)
+            self.assertIsNone(loader)
+            self.assertIsNone(spec)
+
+(Frozen_WindowsRegistryFinderTests,
+ Source_WindowsRegistryFinderTests
+ ) = test_util.test_both(WindowsRegistryFinderTests, machinery=machinery)
+
+@unittest.skipUnless(sys.platform.startswith('win'), 'requires Windows')
+class WindowsExtensionSuffixTests:
+    def test_tagged_suffix(self):
+        suffixes = self.machinery.EXTENSION_SUFFIXES
+        expected_tag = ".cp{0.major}{0.minor}-{1}.pyd".format(sys.version_info,
+            re.sub('[^a-zA-Z0-9]', '_', get_platform()))
+        try:
+            untagged_i = suffixes.index(".pyd")
+        except ValueError:
+            untagged_i = suffixes.index("_d.pyd")
+            expected_tag = "_d" + expected_tag
+
+        self.assertIn(expected_tag, suffixes)
+
+        # Ensure the tags are in the correct order
+        tagged_i = suffixes.index(expected_tag)
+        self.assertLess(tagged_i, untagged_i)
+
+(Frozen_WindowsExtensionSuffixTests,
+ Source_WindowsExtensionSuffixTests
+ ) = test_util.test_both(WindowsExtensionSuffixTests, machinery=machinery)

third_party/python/Lib/test/test_importlib/util.py

@@ -0,0 +1,388 @@
+import builtins
+import contextlib
+import errno
+import functools
+import importlib
+from importlib import machinery, util, invalidate_caches
+import os
+import os.path
+from test import support
+import unittest
+import sys
+import tempfile
+import types
+
+
+BUILTINS = types.SimpleNamespace()
+BUILTINS.good_name = None
+BUILTINS.bad_name = None
+if 'errno' in sys.builtin_module_names:
+    BUILTINS.good_name = 'errno'
+if 'importlib' not in sys.builtin_module_names:
+    BUILTINS.bad_name = 'importlib'
+
+EXTENSIONS = types.SimpleNamespace()
+EXTENSIONS.path = None
+EXTENSIONS.ext = None
+EXTENSIONS.filename = None
+EXTENSIONS.file_path = None
+EXTENSIONS.name = '_testcapi'
+
+def _extension_details():
+    global EXTENSIONS
+    for path in sys.path:
+        for ext in machinery.EXTENSION_SUFFIXES:
+            filename = EXTENSIONS.name + ext
+            file_path = os.path.join(path, filename)
+            if os.path.exists(file_path):
+                EXTENSIONS.path = path
+                EXTENSIONS.ext = ext
+                EXTENSIONS.filename = filename
+                EXTENSIONS.file_path = file_path
+                return
+
+_extension_details()
+
+
+def import_importlib(module_name):
+    """Import a module from importlib both w/ and w/o _frozen_importlib."""
+    fresh = ('importlib',) if '.' in module_name else ()
+    frozen = support.import_fresh_module(module_name)
+    source = support.import_fresh_module(module_name, fresh=fresh,
+                                         blocked=('_frozen_importlib', '_frozen_importlib_external'))
+    return {'Frozen': frozen, 'Source': source}
+
+
+def specialize_class(cls, kind, base=None, **kwargs):
+    # XXX Support passing in submodule names--load (and cache) them?
+    # That would clean up the test modules a bit more.
+    if base is None:
+        base = unittest.TestCase
+    elif not isinstance(base, type):
+        base = base[kind]
+    name = '{}_{}'.format(kind, cls.__name__)
+    bases = (cls, base)
+    specialized = types.new_class(name, bases)
+    specialized.__module__ = cls.__module__
+    specialized._NAME = cls.__name__
+    specialized._KIND = kind
+    for attr, values in kwargs.items():
+        value = values[kind]
+        setattr(specialized, attr, value)
+    return specialized
+
+
+def split_frozen(cls, base=None, **kwargs):
+    frozen = specialize_class(cls, 'Frozen', base, **kwargs)
+    source = specialize_class(cls, 'Source', base, **kwargs)
+    return frozen, source
+
+
+def test_both(test_class, base=None, **kwargs):
+    return split_frozen(test_class, base, **kwargs)
+
+
+CASE_INSENSITIVE_FS = True
+# Windows is the only OS that is *always* case-insensitive
+# (OS X *can* be case-sensitive).
+if sys.platform not in ('win32', 'cygwin'):
+    changed_name = __file__.upper()
+    if changed_name == __file__:
+        changed_name = __file__.lower()
+    if not os.path.exists(changed_name):
+        CASE_INSENSITIVE_FS = False
+
+source_importlib = import_importlib('importlib')['Source']
+__import__ = {'Frozen': staticmethod(builtins.__import__),
+              'Source': staticmethod(source_importlib.__import__)}
+
+
+def case_insensitive_tests(test):
+    """Class decorator that nullifies tests requiring a case-insensitive
+    file system."""
+    return unittest.skipIf(not CASE_INSENSITIVE_FS,
+                            "requires a case-insensitive filesystem")(test)
+
+
+def submodule(parent, name, pkg_dir, content=''):
+    path = os.path.join(pkg_dir, name + '.py')
+    with open(path, 'w') as subfile:
+        subfile.write(content)
+    return '{}.{}'.format(parent, name), path
+
+
+@contextlib.contextmanager
+def uncache(*names):
+    """Uncache a module from sys.modules.
+
+    A basic sanity check is performed to prevent uncaching modules that either
+    cannot/shouldn't be uncached.
+
+    """
+    for name in names:
+        if name in ('sys', 'marshal', 'imp'):
+            raise ValueError(
+                "cannot uncache {0}".format(name))
+        try:
+            del sys.modules[name]
+        except KeyError:
+            pass
+    try:
+        yield
+    finally:
+        for name in names:
+            try:
+                del sys.modules[name]
+            except KeyError:
+                pass
+
+
+@contextlib.contextmanager
+def temp_module(name, content='', *, pkg=False):
+    conflicts = [n for n in sys.modules if n.partition('.')[0] == name]
+    with support.temp_cwd(None) as cwd:
+        with uncache(name, *conflicts):
+            with support.DirsOnSysPath(cwd):
+                invalidate_caches()
+
+                location = os.path.join(cwd, name)
+                if pkg:
+                    modpath = os.path.join(location, '__init__.py')
+                    os.mkdir(name)
+                else:
+                    modpath = location + '.py'
+                    if content is None:
+                        # Make sure the module file gets created.
+                        content = ''
+                if content is not None:
+                    # not a namespace package
+                    with open(modpath, 'w') as modfile:
+                        modfile.write(content)
+                yield location
+
+
+@contextlib.contextmanager
+def import_state(**kwargs):
+    """Context manager to manage the various importers and stored state in the
+    sys module.
+
+    The 'modules' attribute is not supported as the interpreter state stores a
+    pointer to the dict that the interpreter uses internally;
+    reassigning to sys.modules does not have the desired effect.
+
+    """
+    originals = {}
+    try:
+        for attr, default in (('meta_path', []), ('path', []),
+                              ('path_hooks', []),
+                              ('path_importer_cache', {})):
+            originals[attr] = getattr(sys, attr)
+            if attr in kwargs:
+                new_value = kwargs[attr]
+                del kwargs[attr]
+            else:
+                new_value = default
+            setattr(sys, attr, new_value)
+        if len(kwargs):
+            raise ValueError(
+                    'unrecognized arguments: {0}'.format(kwargs.keys()))
+        yield
+    finally:
+        for attr, value in originals.items():
+            setattr(sys, attr, value)
+
+
+class _ImporterMock:
+
+    """Base class to help with creating importer mocks."""
+
+    def __init__(self, *names, module_code={}):
+        self.modules = {}
+        self.module_code = {}
+        for name in names:
+            if not name.endswith('.__init__'):
+                import_name = name
+            else:
+                import_name = name[:-len('.__init__')]
+            if '.' not in name:
+                package = None
+            elif import_name == name:
+                package = name.rsplit('.', 1)[0]
+            else:
+                package = import_name
+            module = types.ModuleType(import_name)
+            module.__loader__ = self
+            module.__file__ = '<mock __file__>'
+            module.__package__ = package
+            module.attr = name
+            if import_name != name:
+                module.__path__ = ['<mock __path__>']
+            self.modules[import_name] = module
+            if import_name in module_code:
+                self.module_code[import_name] = module_code[import_name]
+
+    def __getitem__(self, name):
+        return self.modules[name]
+
+    def __enter__(self):
+        self._uncache = uncache(*self.modules.keys())
+        self._uncache.__enter__()
+        return self
+
+    def __exit__(self, *exc_info):
+        self._uncache.__exit__(None, None, None)
+
+
+class mock_modules(_ImporterMock):
+
+    """Importer mock using PEP 302 APIs."""
+
+    def find_module(self, fullname, path=None):
+        if fullname not in self.modules:
+            return None
+        else:
+            return self
+
+    def load_module(self, fullname):
+        if fullname not in self.modules:
+            raise ImportError
+        else:
+            sys.modules[fullname] = self.modules[fullname]
+            if fullname in self.module_code:
+                try:
+                    self.module_code[fullname]()
+                except Exception:
+                    del sys.modules[fullname]
+                    raise
+            return self.modules[fullname]
+
+
+class mock_spec(_ImporterMock):
+
+    """Importer mock using PEP 451 APIs."""
+
+    def find_spec(self, fullname, path=None, parent=None):
+        try:
+            module = self.modules[fullname]
+        except KeyError:
+            return None
+        spec = util.spec_from_file_location(
+                fullname, module.__file__, loader=self,
+                submodule_search_locations=getattr(module, '__path__', None))
+        return spec
+
+    def create_module(self, spec):
+        if spec.name not in self.modules:
+            raise ImportError
+        return self.modules[spec.name]
+
+    def exec_module(self, module):
+        try:
+            self.module_code[module.__spec__.name]()
+        except KeyError:
+            pass
+
+
+def writes_bytecode_files(fxn):
+    """Decorator to protect sys.dont_write_bytecode from mutation and to skip
+    tests that require it to be set to False."""
+    if sys.dont_write_bytecode:
+        return lambda *args, **kwargs: None
+    @functools.wraps(fxn)
+    def wrapper(*args, **kwargs):
+        original = sys.dont_write_bytecode
+        sys.dont_write_bytecode = False
+        try:
+            to_return = fxn(*args, **kwargs)
+        finally:
+            sys.dont_write_bytecode = original
+        return to_return
+    return wrapper
+
+
+def ensure_bytecode_path(bytecode_path):
+    """Ensure that the __pycache__ directory for PEP 3147 pyc file exists.
+
+    :param bytecode_path: File system path to PEP 3147 pyc file.
+    """
+    try:
+        os.mkdir(os.path.dirname(bytecode_path))
+    except OSError as error:
+        if error.errno != errno.EEXIST:
+            raise
+
+
+@contextlib.contextmanager
+def create_modules(*names):
+    """Temporarily create each named module with an attribute (named 'attr')
+    that contains the name passed into the context manager that caused the
+    creation of the module.
+
+    All files are created in a temporary directory returned by
+    tempfile.mkdtemp(). This directory is inserted at the beginning of
+    sys.path. When the context manager exits all created files (source and
+    bytecode) are explicitly deleted.
+
+    No magic is performed when creating packages! This means that if you create
+    a module within a package you must also create the package's __init__ as
+    well.
+
+    """
+    source = 'attr = {0!r}'
+    created_paths = []
+    mapping = {}
+    state_manager = None
+    uncache_manager = None
+    try:
+        temp_dir = tempfile.mkdtemp()
+        mapping['.root'] = temp_dir
+        import_names = set()
+        for name in names:
+            if not name.endswith('__init__'):
+                import_name = name
+            else:
+                import_name = name[:-len('.__init__')]
+            import_names.add(import_name)
+            if import_name in sys.modules:
+                del sys.modules[import_name]
+            name_parts = name.split('.')
+            file_path = temp_dir
+            for directory in name_parts[:-1]:
+                file_path = os.path.join(file_path, directory)
+                if not os.path.exists(file_path):
+                    os.mkdir(file_path)
+                    created_paths.append(file_path)
+            file_path = os.path.join(file_path, name_parts[-1] + '.py')
+            with open(file_path, 'w') as file:
+                file.write(source.format(name))
+            created_paths.append(file_path)
+            mapping[name] = file_path
+        uncache_manager = uncache(*import_names)
+        uncache_manager.__enter__()
+        state_manager = import_state(path=[temp_dir])
+        state_manager.__enter__()
+        yield mapping
+    finally:
+        if state_manager is not None:
+            state_manager.__exit__(None, None, None)
+        if uncache_manager is not None:
+            uncache_manager.__exit__(None, None, None)
+        support.rmtree(temp_dir)
+
+
+def mock_path_hook(*entries, importer):
+    """A mock sys.path_hooks entry."""
+    def hook(entry):
+        if entry not in entries:
+            raise ImportError
+        return importer
+    return hook
+
+
+class CASEOKTestBase:
+
+    def caseok_env_changed(self, *, should_exist):
+        possibilities = b'PYTHONCASEOK', 'PYTHONCASEOK'
+        if any(x in self.importlib._bootstrap_external._os.environ
+                    for x in possibilities) != should_exist:
+            self.skipTest('os.environ changes not reflected in _os.environ')