Add Python JSON tests (#407)

third_party/python/Lib/test/Python.asdl

@@ -0,0 +1,132 @@
+-- ASDL's 7 builtin types are:
+-- identifier, int, string, bytes, object, singleton, constant
+--
+-- singleton: None, True or False
+-- constant can be None, whereas None means "no value" for object.
+
+module Python
+{
+    mod = Module(stmt* body)
+        | Interactive(stmt* body)
+        | Expression(expr body)
+
+        -- not really an actual node but useful in Jython's typesystem.
+        | Suite(stmt* body)
+
+    stmt = FunctionDef(identifier name, arguments args,
+                       stmt* body, expr* decorator_list, expr? returns)
+          | AsyncFunctionDef(identifier name, arguments args,
+                             stmt* body, expr* decorator_list, expr? returns)
+
+          | ClassDef(identifier name,
+             expr* bases,
+             keyword* keywords,
+             stmt* body,
+             expr* decorator_list)
+          | Return(expr? value)
+
+          | Delete(expr* targets)
+          | Assign(expr* targets, expr value)
+          | AugAssign(expr target, operator op, expr value)
+          -- 'simple' indicates that we annotate simple name without parens
+          | AnnAssign(expr target, expr annotation, expr? value, int simple)
+
+          -- use 'orelse' because else is a keyword in target languages
+          | For(expr target, expr iter, stmt* body, stmt* orelse)
+          | AsyncFor(expr target, expr iter, stmt* body, stmt* orelse)
+          | While(expr test, stmt* body, stmt* orelse)
+          | If(expr test, stmt* body, stmt* orelse)
+          | With(withitem* items, stmt* body)
+          | AsyncWith(withitem* items, stmt* body)
+
+          | Raise(expr? exc, expr? cause)
+          | Try(stmt* body, excepthandler* handlers, stmt* orelse, stmt* finalbody)
+          | Assert(expr test, expr? msg)
+
+          | Import(alias* names)
+          | ImportFrom(identifier? module, alias* names, int? level)
+
+          | Global(identifier* names)
+          | Nonlocal(identifier* names)
+          | Expr(expr value)
+          | Pass | Break | Continue
+
+          -- XXX Jython will be different
+          -- col_offset is the byte offset in the utf8 string the parser uses
+          attributes (int lineno, int col_offset)
+
+          -- BoolOp() can use left & right?
+    expr = BoolOp(boolop op, expr* values)
+         | BinOp(expr left, operator op, expr right)
+         | UnaryOp(unaryop op, expr operand)
+         | Lambda(arguments args, expr body)
+         | IfExp(expr test, expr body, expr orelse)
+         | Dict(expr* keys, expr* values)
+         | Set(expr* elts)
+         | ListComp(expr elt, comprehension* generators)
+         | SetComp(expr elt, comprehension* generators)
+         | DictComp(expr key, expr value, comprehension* generators)
+         | GeneratorExp(expr elt, comprehension* generators)
+         -- the grammar constrains where yield expressions can occur
+         | Await(expr value)
+         | Yield(expr? value)
+         | YieldFrom(expr value)
+         -- need sequences for compare to distinguish between
+         -- x < 4 < 3 and (x < 4) < 3
+         | Compare(expr left, cmpop* ops, expr* comparators)
+         | Call(expr func, expr* args, keyword* keywords)
+         | Num(object n) -- a number as a PyObject.
+         | Str(string s) -- need to specify raw, unicode, etc?
+         | FormattedValue(expr value, int? conversion, expr? format_spec)
+         | JoinedStr(expr* values)
+         | Bytes(bytes s)
+         | NameConstant(singleton value)
+         | Ellipsis
+         | Constant(constant value)
+
+         -- the following expression can appear in assignment context
+         | Attribute(expr value, identifier attr, expr_context ctx)
+         | Subscript(expr value, slice slice, expr_context ctx)
+         | Starred(expr value, expr_context ctx)
+         | Name(identifier id, expr_context ctx)
+         | List(expr* elts, expr_context ctx)
+         | Tuple(expr* elts, expr_context ctx)
+
+          -- col_offset is the byte offset in the utf8 string the parser uses
+          attributes (int lineno, int col_offset)
+
+    expr_context = Load | Store | Del | AugLoad | AugStore | Param
+
+    slice = Slice(expr? lower, expr? upper, expr? step)
+          | ExtSlice(slice* dims)
+          | Index(expr value)
+
+    boolop = And | Or
+
+    operator = Add | Sub | Mult | MatMult | Div | Mod | Pow | LShift
+                 | RShift | BitOr | BitXor | BitAnd | FloorDiv
+
+    unaryop = Invert | Not | UAdd | USub
+
+    cmpop = Eq | NotEq | Lt | LtE | Gt | GtE | Is | IsNot | In | NotIn
+
+    comprehension = (expr target, expr iter, expr* ifs, int is_async)
+
+    excepthandler = ExceptHandler(expr? type, identifier? name, stmt* body)
+                    attributes (int lineno, int col_offset)
+
+    arguments = (arg* args, arg? vararg, arg* kwonlyargs, expr* kw_defaults,
+                 arg? kwarg, expr* defaults)
+
+    arg = (identifier arg, expr? annotation)
+           attributes (int lineno, int col_offset)
+
+    -- keyword arguments supplied to call (NULL identifier for **kwargs)
+    keyword = (identifier? arg, expr value)
+
+    -- import name with optional 'as' alias.
+    alias = (identifier name, identifier? asname)
+
+    withitem = (expr context_expr, expr? optional_vars)
+}
+