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Diffstat (limited to 'third_party/python/Mako/mako/pyparser.py')
| -rw-r--r-- | third_party/python/Mako/mako/pyparser.py | 242 |
1 files changed, 242 insertions, 0 deletions
diff --git a/third_party/python/Mako/mako/pyparser.py b/third_party/python/Mako/mako/pyparser.py new file mode 100644 index 0000000000..b16672d60c --- /dev/null +++ b/third_party/python/Mako/mako/pyparser.py @@ -0,0 +1,242 @@ +# mako/pyparser.py +# Copyright 2006-2020 the Mako authors and contributors <see AUTHORS file> +# +# This module is part of Mako and is released under +# the MIT License: http://www.opensource.org/licenses/mit-license.php + +"""Handles parsing of Python code. + +Parsing to AST is done via _ast on Python > 2.5, otherwise the compiler +module is used. +""" + +import operator + +import _ast + +from mako import _ast_util +from mako import compat +from mako import exceptions +from mako import util +from mako.compat import arg_stringname + +if compat.py3k: + # words that cannot be assigned to (notably + # smaller than the total keys in __builtins__) + reserved = set(["True", "False", "None", "print"]) + + # the "id" attribute on a function node + arg_id = operator.attrgetter("arg") +else: + # words that cannot be assigned to (notably + # smaller than the total keys in __builtins__) + reserved = set(["True", "False", "None"]) + + # the "id" attribute on a function node + arg_id = operator.attrgetter("id") + +util.restore__ast(_ast) + + +def parse(code, mode="exec", **exception_kwargs): + """Parse an expression into AST""" + + try: + return _ast_util.parse(code, "<unknown>", mode) + except Exception: + raise exceptions.SyntaxException( + "(%s) %s (%r)" + % ( + compat.exception_as().__class__.__name__, + compat.exception_as(), + code[0:50], + ), + **exception_kwargs + ) + + +class FindIdentifiers(_ast_util.NodeVisitor): + def __init__(self, listener, **exception_kwargs): + self.in_function = False + self.in_assign_targets = False + self.local_ident_stack = set() + self.listener = listener + self.exception_kwargs = exception_kwargs + + def _add_declared(self, name): + if not self.in_function: + self.listener.declared_identifiers.add(name) + else: + self.local_ident_stack.add(name) + + def visit_ClassDef(self, node): + self._add_declared(node.name) + + def visit_Assign(self, node): + + # flip around the visiting of Assign so the expression gets + # evaluated first, in the case of a clause like "x=x+5" (x + # is undeclared) + + self.visit(node.value) + in_a = self.in_assign_targets + self.in_assign_targets = True + for n in node.targets: + self.visit(n) + self.in_assign_targets = in_a + + if compat.py3k: + + # ExceptHandler is in Python 2, but this block only works in + # Python 3 (and is required there) + + def visit_ExceptHandler(self, node): + if node.name is not None: + self._add_declared(node.name) + if node.type is not None: + self.visit(node.type) + for statement in node.body: + self.visit(statement) + + def visit_Lambda(self, node, *args): + self._visit_function(node, True) + + def visit_FunctionDef(self, node): + self._add_declared(node.name) + self._visit_function(node, False) + + def _expand_tuples(self, args): + for arg in args: + if isinstance(arg, _ast.Tuple): + for n in arg.elts: + yield n + else: + yield arg + + def _visit_function(self, node, islambda): + + # push function state onto stack. dont log any more + # identifiers as "declared" until outside of the function, + # but keep logging identifiers as "undeclared". track + # argument names in each function header so they arent + # counted as "undeclared" + + inf = self.in_function + self.in_function = True + + local_ident_stack = self.local_ident_stack + self.local_ident_stack = local_ident_stack.union( + [arg_id(arg) for arg in self._expand_tuples(node.args.args)] + ) + if islambda: + self.visit(node.body) + else: + for n in node.body: + self.visit(n) + self.in_function = inf + self.local_ident_stack = local_ident_stack + + def visit_For(self, node): + + # flip around visit + + self.visit(node.iter) + self.visit(node.target) + for statement in node.body: + self.visit(statement) + for statement in node.orelse: + self.visit(statement) + + def visit_Name(self, node): + if isinstance(node.ctx, _ast.Store): + # this is eqiuvalent to visit_AssName in + # compiler + self._add_declared(node.id) + elif ( + node.id not in reserved + and node.id not in self.listener.declared_identifiers + and node.id not in self.local_ident_stack + ): + self.listener.undeclared_identifiers.add(node.id) + + def visit_Import(self, node): + for name in node.names: + if name.asname is not None: + self._add_declared(name.asname) + else: + self._add_declared(name.name.split(".")[0]) + + def visit_ImportFrom(self, node): + for name in node.names: + if name.asname is not None: + self._add_declared(name.asname) + else: + if name.name == "*": + raise exceptions.CompileException( + "'import *' is not supported, since all identifier " + "names must be explicitly declared. Please use the " + "form 'from <modulename> import <name1>, <name2>, " + "...' instead.", + **self.exception_kwargs + ) + self._add_declared(name.name) + + +class FindTuple(_ast_util.NodeVisitor): + def __init__(self, listener, code_factory, **exception_kwargs): + self.listener = listener + self.exception_kwargs = exception_kwargs + self.code_factory = code_factory + + def visit_Tuple(self, node): + for n in node.elts: + p = self.code_factory(n, **self.exception_kwargs) + self.listener.codeargs.append(p) + self.listener.args.append(ExpressionGenerator(n).value()) + ldi = self.listener.declared_identifiers + self.listener.declared_identifiers = ldi.union( + p.declared_identifiers + ) + lui = self.listener.undeclared_identifiers + self.listener.undeclared_identifiers = lui.union( + p.undeclared_identifiers + ) + + +class ParseFunc(_ast_util.NodeVisitor): + def __init__(self, listener, **exception_kwargs): + self.listener = listener + self.exception_kwargs = exception_kwargs + + def visit_FunctionDef(self, node): + self.listener.funcname = node.name + + argnames = [arg_id(arg) for arg in node.args.args] + if node.args.vararg: + argnames.append(arg_stringname(node.args.vararg)) + + if compat.py2k: + # kw-only args don't exist in Python 2 + kwargnames = [] + else: + kwargnames = [arg_id(arg) for arg in node.args.kwonlyargs] + if node.args.kwarg: + kwargnames.append(arg_stringname(node.args.kwarg)) + self.listener.argnames = argnames + self.listener.defaults = node.args.defaults # ast + self.listener.kwargnames = kwargnames + if compat.py2k: + self.listener.kwdefaults = [] + else: + self.listener.kwdefaults = node.args.kw_defaults + self.listener.varargs = node.args.vararg + self.listener.kwargs = node.args.kwarg + + +class ExpressionGenerator(object): + def __init__(self, astnode): + self.generator = _ast_util.SourceGenerator(" " * 4) + self.generator.visit(astnode) + + def value(self): + return "".join(self.generator.result) |