python-3.6.zip added from Github

README.cosmo contains the necessary links.

third_party/python/Lib/lib2to3/pgen2/driver.py

@@ -0,0 +1,181 @@
+# Copyright 2004-2005 Elemental Security, Inc. All Rights Reserved.
+# Licensed to PSF under a Contributor Agreement.
+
+# Modifications:
+# Copyright 2006 Google, Inc. All Rights Reserved.
+# Licensed to PSF under a Contributor Agreement.
+
+"""Parser driver.
+
+This provides a high-level interface to parse a file into a syntax tree.
+
+"""
+
+__author__ = "Guido van Rossum <guido@python.org>"
+
+__all__ = ["Driver", "load_grammar"]
+
+# Python imports
+import codecs
+import io
+import os
+import logging
+import pkgutil
+import sys
+
+# Pgen imports
+from . import grammar, parse, token, tokenize, pgen
+
+
+class Driver(object):
+
+    def __init__(self, grammar, convert=None, logger=None):
+        self.grammar = grammar
+        if logger is None:
+            logger = logging.getLogger()
+        self.logger = logger
+        self.convert = convert
+
+    def parse_tokens(self, tokens, debug=False):
+        """Parse a series of tokens and return the syntax tree."""
+        # XXX Move the prefix computation into a wrapper around tokenize.
+        p = parse.Parser(self.grammar, self.convert)
+        p.setup()
+        lineno = 1
+        column = 0
+        type = value = start = end = line_text = None
+        prefix = ""
+        for quintuple in tokens:
+            type, value, start, end, line_text = quintuple
+            if start != (lineno, column):
+                assert (lineno, column) <= start, ((lineno, column), start)
+                s_lineno, s_column = start
+                if lineno < s_lineno:
+                    prefix += "\n" * (s_lineno - lineno)
+                    lineno = s_lineno
+                    column = 0
+                if column < s_column:
+                    prefix += line_text[column:s_column]
+                    column = s_column
+            if type in (tokenize.COMMENT, tokenize.NL):
+                prefix += value
+                lineno, column = end
+                if value.endswith("\n"):
+                    lineno += 1
+                    column = 0
+                continue
+            if type == token.OP:
+                type = grammar.opmap[value]
+            if debug:
+                self.logger.debug("%s %r (prefix=%r)",
+                                  token.tok_name[type], value, prefix)
+            if p.addtoken(type, value, (prefix, start)):
+                if debug:
+                    self.logger.debug("Stop.")
+                break
+            prefix = ""
+            lineno, column = end
+            if value.endswith("\n"):
+                lineno += 1
+                column = 0
+        else:
+            # We never broke out -- EOF is too soon (how can this happen???)
+            raise parse.ParseError("incomplete input",
+                                   type, value, (prefix, start))
+        return p.rootnode
+
+    def parse_stream_raw(self, stream, debug=False):
+        """Parse a stream and return the syntax tree."""
+        tokens = tokenize.generate_tokens(stream.readline)
+        return self.parse_tokens(tokens, debug)
+
+    def parse_stream(self, stream, debug=False):
+        """Parse a stream and return the syntax tree."""
+        return self.parse_stream_raw(stream, debug)
+
+    def parse_file(self, filename, encoding=None, debug=False):
+        """Parse a file and return the syntax tree."""
+        stream = codecs.open(filename, "r", encoding)
+        try:
+            return self.parse_stream(stream, debug)
+        finally:
+            stream.close()
+
+    def parse_string(self, text, debug=False):
+        """Parse a string and return the syntax tree."""
+        tokens = tokenize.generate_tokens(io.StringIO(text).readline)
+        return self.parse_tokens(tokens, debug)
+
+
+def _generate_pickle_name(gt):
+    head, tail = os.path.splitext(gt)
+    if tail == ".txt":
+        tail = ""
+    return head + tail + ".".join(map(str, sys.version_info)) + ".pickle"
+
+
+def load_grammar(gt="Grammar.txt", gp=None,
+                 save=True, force=False, logger=None):
+    """Load the grammar (maybe from a pickle)."""
+    if logger is None:
+        logger = logging.getLogger()
+    gp = _generate_pickle_name(gt) if gp is None else gp
+    if force or not _newer(gp, gt):
+        logger.info("Generating grammar tables from %s", gt)
+        g = pgen.generate_grammar(gt)
+        if save:
+            logger.info("Writing grammar tables to %s", gp)
+            try:
+                g.dump(gp)
+            except OSError as e:
+                logger.info("Writing failed: %s", e)
+    else:
+        g = grammar.Grammar()
+        g.load(gp)
+    return g
+
+
+def _newer(a, b):
+    """Inquire whether file a was written since file b."""
+    if not os.path.exists(a):
+        return False
+    if not os.path.exists(b):
+        return True
+    return os.path.getmtime(a) >= os.path.getmtime(b)
+
+
+def load_packaged_grammar(package, grammar_source):
+    """Normally, loads a pickled grammar by doing
+        pkgutil.get_data(package, pickled_grammar)
+    where *pickled_grammar* is computed from *grammar_source* by adding the
+    Python version and using a ``.pickle`` extension.
+
+    However, if *grammar_source* is an extant file, load_grammar(grammar_source)
+    is called instead. This facilitates using a packaged grammar file when needed
+    but preserves load_grammar's automatic regeneration behavior when possible.
+
+    """
+    if os.path.isfile(grammar_source):
+        return load_grammar(grammar_source)
+    pickled_name = _generate_pickle_name(os.path.basename(grammar_source))
+    data = pkgutil.get_data(package, pickled_name)
+    g = grammar.Grammar()
+    g.loads(data)
+    return g
+
+
+def main(*args):
+    """Main program, when run as a script: produce grammar pickle files.
+
+    Calls load_grammar for each argument, a path to a grammar text file.
+    """
+    if not args:
+        args = sys.argv[1:]
+    logging.basicConfig(level=logging.INFO, stream=sys.stdout,
+                        format='%(message)s')
+    for gt in args:
+        load_grammar(gt, save=True, force=True)
+    return True
+
+if __name__ == "__main__":
+    sys.exit(int(not main()))