mirror of
https://github.com/thegeeklab/ansible-later.git
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1699 lines
60 KiB
Python
1699 lines
60 KiB
Python
"""
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Main module.
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Implement the central Checker class.
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Also, it models the Bindings and Scopes.
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"""
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import __future__
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import ast
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import bisect
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import collections
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import doctest
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import functools
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import os
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import re
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import sys
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import tokenize
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from pyflakes import messages
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PY2 = sys.version_info < (3, 0)
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PY35_PLUS = sys.version_info >= (3, 5) # Python 3.5 and above
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PY36_PLUS = sys.version_info >= (3, 6) # Python 3.6 and above
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PY38_PLUS = sys.version_info >= (3, 8)
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try:
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sys.pypy_version_info
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PYPY = True
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except AttributeError:
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PYPY = False
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builtin_vars = dir(__import__('__builtin__' if PY2 else 'builtins'))
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if PY2:
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tokenize_tokenize = tokenize.generate_tokens
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else:
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tokenize_tokenize = tokenize.tokenize
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if PY2:
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def getNodeType(node_class):
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# workaround str.upper() which is locale-dependent
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return str(unicode(node_class.__name__).upper())
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def get_raise_argument(node):
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return node.type
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else:
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def getNodeType(node_class):
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return node_class.__name__.upper()
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def get_raise_argument(node):
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return node.exc
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# Silence `pyflakes` from reporting `undefined name 'unicode'` in Python 3.
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unicode = str
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# Python >= 3.3 uses ast.Try instead of (ast.TryExcept + ast.TryFinally)
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if PY2:
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def getAlternatives(n):
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if isinstance(n, (ast.If, ast.TryFinally)):
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return [n.body]
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if isinstance(n, ast.TryExcept):
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return [n.body + n.orelse] + [[hdl] for hdl in n.handlers]
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else:
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def getAlternatives(n):
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if isinstance(n, ast.If):
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return [n.body]
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if isinstance(n, ast.Try):
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return [n.body + n.orelse] + [[hdl] for hdl in n.handlers]
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if PY35_PLUS:
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FOR_TYPES = (ast.For, ast.AsyncFor)
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LOOP_TYPES = (ast.While, ast.For, ast.AsyncFor)
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else:
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FOR_TYPES = (ast.For,)
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LOOP_TYPES = (ast.While, ast.For)
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# https://github.com/python/typed_ast/blob/55420396/ast27/Parser/tokenizer.c#L102-L104
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TYPE_COMMENT_RE = re.compile(r'^#\s*type:\s*')
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# https://github.com/python/typed_ast/blob/55420396/ast27/Parser/tokenizer.c#L1400
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TYPE_IGNORE_RE = re.compile(TYPE_COMMENT_RE.pattern + r'ignore\s*(#|$)')
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# https://github.com/python/typed_ast/blob/55420396/ast27/Grammar/Grammar#L147
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TYPE_FUNC_RE = re.compile(r'^(\(.*?\))\s*->\s*(.*)$')
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class _FieldsOrder(dict):
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"""Fix order of AST node fields."""
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def _get_fields(self, node_class):
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# handle iter before target, and generators before element
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fields = node_class._fields
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if 'iter' in fields:
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key_first = 'iter'.find
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elif 'generators' in fields:
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key_first = 'generators'.find
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else:
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key_first = 'value'.find
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return tuple(sorted(fields, key=key_first, reverse=True))
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def __missing__(self, node_class):
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self[node_class] = fields = self._get_fields(node_class)
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return fields
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def counter(items):
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"""
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Simplest required implementation of collections.Counter. Required as 2.6
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does not have Counter in collections.
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"""
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results = {}
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for item in items:
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results[item] = results.get(item, 0) + 1
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return results
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def iter_child_nodes(node, omit=None, _fields_order=_FieldsOrder()):
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"""
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Yield all direct child nodes of *node*, that is, all fields that
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are nodes and all items of fields that are lists of nodes.
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:param node: AST node to be iterated upon
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:param omit: String or tuple of strings denoting the
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attributes of the node to be omitted from
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further parsing
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:param _fields_order: Order of AST node fields
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"""
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for name in _fields_order[node.__class__]:
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if omit and name in omit:
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continue
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field = getattr(node, name, None)
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if isinstance(field, ast.AST):
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yield field
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elif isinstance(field, list):
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for item in field:
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yield item
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def convert_to_value(item):
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if isinstance(item, ast.Str):
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return item.s
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elif hasattr(ast, 'Bytes') and isinstance(item, ast.Bytes):
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return item.s
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elif isinstance(item, ast.Tuple):
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return tuple(convert_to_value(i) for i in item.elts)
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elif isinstance(item, ast.Num):
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return item.n
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elif isinstance(item, ast.Name):
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result = VariableKey(item=item)
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constants_lookup = {
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'True': True,
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'False': False,
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'None': None,
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}
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return constants_lookup.get(
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result.name,
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result,
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)
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elif (not PY2) and isinstance(item, ast.NameConstant):
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# None, True, False are nameconstants in python3, but names in 2
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return item.value
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else:
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return UnhandledKeyType()
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def is_notimplemented_name_node(node):
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return isinstance(node, ast.Name) and getNodeName(node) == 'NotImplemented'
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class Binding(object):
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"""
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Represents the binding of a value to a name.
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The checker uses this to keep track of which names have been bound and
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which names have not. See L{Assignment} for a special type of binding that
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is checked with stricter rules.
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@ivar used: pair of (L{Scope}, node) indicating the scope and
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the node that this binding was last used.
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"""
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def __init__(self, name, source):
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self.name = name
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self.source = source
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self.used = False
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def __str__(self):
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return self.name
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def __repr__(self):
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return '<%s object %r from line %r at 0x%x>' % (self.__class__.__name__,
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self.name,
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self.source.lineno,
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id(self))
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def redefines(self, other):
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return isinstance(other, Definition) and self.name == other.name
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class Definition(Binding):
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"""
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A binding that defines a function or a class.
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"""
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class Builtin(Definition):
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"""A definition created for all Python builtins."""
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def __init__(self, name):
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super(Builtin, self).__init__(name, None)
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def __repr__(self):
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return '<%s object %r at 0x%x>' % (self.__class__.__name__,
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self.name,
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id(self))
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class UnhandledKeyType(object):
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"""
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A dictionary key of a type that we cannot or do not check for duplicates.
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"""
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class VariableKey(object):
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"""
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A dictionary key which is a variable.
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@ivar item: The variable AST object.
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"""
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def __init__(self, item):
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self.name = item.id
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def __eq__(self, compare):
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return (
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compare.__class__ == self.__class__ and
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compare.name == self.name
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)
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def __hash__(self):
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return hash(self.name)
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class Importation(Definition):
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"""
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A binding created by an import statement.
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@ivar fullName: The complete name given to the import statement,
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possibly including multiple dotted components.
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@type fullName: C{str}
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"""
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def __init__(self, name, source, full_name=None):
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self.fullName = full_name or name
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self.redefined = []
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super(Importation, self).__init__(name, source)
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def redefines(self, other):
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if isinstance(other, SubmoduleImportation):
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# See note in SubmoduleImportation about RedefinedWhileUnused
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return self.fullName == other.fullName
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return isinstance(other, Definition) and self.name == other.name
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def _has_alias(self):
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"""Return whether importation needs an as clause."""
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return not self.fullName.split('.')[-1] == self.name
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@property
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def source_statement(self):
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"""Generate a source statement equivalent to the import."""
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if self._has_alias():
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return 'import %s as %s' % (self.fullName, self.name)
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else:
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return 'import %s' % self.fullName
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def __str__(self):
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"""Return import full name with alias."""
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if self._has_alias():
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return self.fullName + ' as ' + self.name
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else:
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return self.fullName
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class SubmoduleImportation(Importation):
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"""
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A binding created by a submodule import statement.
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A submodule import is a special case where the root module is implicitly
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imported, without an 'as' clause, and the submodule is also imported.
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Python does not restrict which attributes of the root module may be used.
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This class is only used when the submodule import is without an 'as' clause.
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pyflakes handles this case by registering the root module name in the scope,
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allowing any attribute of the root module to be accessed.
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RedefinedWhileUnused is suppressed in `redefines` unless the submodule
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name is also the same, to avoid false positives.
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"""
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def __init__(self, name, source):
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# A dot should only appear in the name when it is a submodule import
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assert '.' in name and (not source or isinstance(source, ast.Import))
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package_name = name.split('.')[0]
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super(SubmoduleImportation, self).__init__(package_name, source)
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self.fullName = name
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def redefines(self, other):
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if isinstance(other, Importation):
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return self.fullName == other.fullName
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return super(SubmoduleImportation, self).redefines(other)
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def __str__(self):
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return self.fullName
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@property
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def source_statement(self):
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return 'import ' + self.fullName
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class ImportationFrom(Importation):
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def __init__(self, name, source, module, real_name=None):
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self.module = module
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self.real_name = real_name or name
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if module.endswith('.'):
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full_name = module + self.real_name
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else:
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full_name = module + '.' + self.real_name
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super(ImportationFrom, self).__init__(name, source, full_name)
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def __str__(self):
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"""Return import full name with alias."""
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if self.real_name != self.name:
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return self.fullName + ' as ' + self.name
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else:
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return self.fullName
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@property
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def source_statement(self):
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if self.real_name != self.name:
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return 'from %s import %s as %s' % (self.module,
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self.real_name,
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self.name)
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else:
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return 'from %s import %s' % (self.module, self.name)
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class StarImportation(Importation):
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"""A binding created by a 'from x import *' statement."""
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def __init__(self, name, source):
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super(StarImportation, self).__init__('*', source)
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# Each star importation needs a unique name, and
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# may not be the module name otherwise it will be deemed imported
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self.name = name + '.*'
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self.fullName = name
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@property
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def source_statement(self):
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return 'from ' + self.fullName + ' import *'
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def __str__(self):
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# When the module ends with a ., avoid the ambiguous '..*'
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if self.fullName.endswith('.'):
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return self.source_statement
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else:
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return self.name
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class FutureImportation(ImportationFrom):
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"""
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A binding created by a from `__future__` import statement.
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`__future__` imports are implicitly used.
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"""
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def __init__(self, name, source, scope):
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super(FutureImportation, self).__init__(name, source, '__future__')
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self.used = (scope, source)
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class Argument(Binding):
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"""
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Represents binding a name as an argument.
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"""
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class Assignment(Binding):
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"""
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Represents binding a name with an explicit assignment.
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The checker will raise warnings for any Assignment that isn't used. Also,
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the checker does not consider assignments in tuple/list unpacking to be
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Assignments, rather it treats them as simple Bindings.
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"""
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class FunctionDefinition(Definition):
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pass
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class ClassDefinition(Definition):
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pass
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class ExportBinding(Binding):
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"""
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A binding created by an C{__all__} assignment. If the names in the list
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can be determined statically, they will be treated as names for export and
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additional checking applied to them.
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The only recognized C{__all__} assignment via list concatenation is in the
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following format:
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__all__ = ['a'] + ['b'] + ['c']
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Names which are imported and not otherwise used but appear in the value of
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C{__all__} will not have an unused import warning reported for them.
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"""
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def __init__(self, name, source, scope):
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if '__all__' in scope and isinstance(source, ast.AugAssign):
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self.names = list(scope['__all__'].names)
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else:
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self.names = []
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def _add_to_names(container):
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for node in container.elts:
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if isinstance(node, ast.Str):
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self.names.append(node.s)
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if isinstance(source.value, (ast.List, ast.Tuple)):
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_add_to_names(source.value)
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# If concatenating lists
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elif isinstance(source.value, ast.BinOp):
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currentValue = source.value
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while isinstance(currentValue.right, ast.List):
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left = currentValue.left
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right = currentValue.right
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_add_to_names(right)
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# If more lists are being added
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if isinstance(left, ast.BinOp):
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currentValue = left
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# If just two lists are being added
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|
elif isinstance(left, ast.List):
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_add_to_names(left)
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# All lists accounted for - done
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break
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# If not list concatenation
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else:
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break
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super(ExportBinding, self).__init__(name, source)
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|
|
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class Scope(dict):
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importStarred = False # set to True when import * is found
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def __repr__(self):
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scope_cls = self.__class__.__name__
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return '<%s at 0x%x %s>' % (scope_cls, id(self), dict.__repr__(self))
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|
|
|
|
class ClassScope(Scope):
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pass
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|
|
|
|
class FunctionScope(Scope):
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|
"""
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I represent a name scope for a function.
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|
@ivar globals: Names declared 'global' in this function.
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"""
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|
usesLocals = False
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|
alwaysUsed = {'__tracebackhide__', '__traceback_info__',
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|
'__traceback_supplement__'}
|
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|
|
def __init__(self):
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|
super(FunctionScope, self).__init__()
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|
# Simplify: manage the special locals as globals
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|
self.globals = self.alwaysUsed.copy()
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|
self.returnValue = None # First non-empty return
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|
self.isGenerator = False # Detect a generator
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|
|
|
def unusedAssignments(self):
|
|
"""
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|
Return a generator for the assignments which have not been used.
|
|
"""
|
|
for name, binding in self.items():
|
|
if (not binding.used and
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name != '_' and # see issue #202
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|
name not in self.globals and
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|
not self.usesLocals and
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|
isinstance(binding, Assignment)):
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|
yield name, binding
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|
|
|
|
|
class GeneratorScope(Scope):
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|
pass
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|
|
|
|
|
class ModuleScope(Scope):
|
|
"""Scope for a module."""
|
|
_futures_allowed = True
|
|
_annotations_future_enabled = False
|
|
|
|
|
|
class DoctestScope(ModuleScope):
|
|
"""Scope for a doctest."""
|
|
|
|
|
|
class DummyNode(object):
|
|
"""Used in place of an `ast.AST` to set error message positions"""
|
|
def __init__(self, lineno, col_offset):
|
|
self.lineno = lineno
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|
self.col_offset = col_offset
|
|
|
|
|
|
# Globally defined names which are not attributes of the builtins module, or
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|
# are only present on some platforms.
|
|
_MAGIC_GLOBALS = ['__file__', '__builtins__', 'WindowsError']
|
|
# module scope annotation will store in `__annotations__`, see also PEP 526.
|
|
if PY36_PLUS:
|
|
_MAGIC_GLOBALS.append('__annotations__')
|
|
|
|
|
|
def getNodeName(node):
|
|
# Returns node.id, or node.name, or None
|
|
if hasattr(node, 'id'): # One of the many nodes with an id
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|
return node.id
|
|
if hasattr(node, 'name'): # an ExceptHandler node
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|
return node.name
|
|
|
|
|
|
def is_typing_overload(value, scope):
|
|
def is_typing_overload_decorator(node):
|
|
return (
|
|
(
|
|
isinstance(node, ast.Name) and
|
|
node.id in scope and
|
|
isinstance(scope[node.id], ImportationFrom) and
|
|
scope[node.id].fullName == 'typing.overload'
|
|
) or (
|
|
isinstance(node, ast.Attribute) and
|
|
isinstance(node.value, ast.Name) and
|
|
node.value.id == 'typing' and
|
|
node.attr == 'overload'
|
|
)
|
|
)
|
|
|
|
return (
|
|
isinstance(value.source, ast.FunctionDef) and
|
|
len(value.source.decorator_list) == 1 and
|
|
is_typing_overload_decorator(value.source.decorator_list[0])
|
|
)
|
|
|
|
|
|
def make_tokens(code):
|
|
# PY3: tokenize.tokenize requires readline of bytes
|
|
if not isinstance(code, bytes):
|
|
code = code.encode('UTF-8')
|
|
lines = iter(code.splitlines(True))
|
|
# next(lines, b'') is to prevent an error in pypy3
|
|
return tuple(tokenize_tokenize(lambda: next(lines, b'')))
|
|
|
|
|
|
class _TypeableVisitor(ast.NodeVisitor):
|
|
"""Collect the line number and nodes which are deemed typeable by
|
|
PEP 484
|
|
|
|
https://www.python.org/dev/peps/pep-0484/#type-comments
|
|
"""
|
|
def __init__(self):
|
|
self.typeable_lines = [] # type: List[int]
|
|
self.typeable_nodes = {} # type: Dict[int, ast.AST]
|
|
|
|
def _typeable(self, node):
|
|
# if there is more than one typeable thing on a line last one wins
|
|
self.typeable_lines.append(node.lineno)
|
|
self.typeable_nodes[node.lineno] = node
|
|
|
|
self.generic_visit(node)
|
|
|
|
visit_Assign = visit_For = visit_FunctionDef = visit_With = _typeable
|
|
visit_AsyncFor = visit_AsyncFunctionDef = visit_AsyncWith = _typeable
|
|
|
|
|
|
def _collect_type_comments(tree, tokens):
|
|
visitor = _TypeableVisitor()
|
|
visitor.visit(tree)
|
|
|
|
type_comments = collections.defaultdict(list)
|
|
for tp, text, start, _, _ in tokens:
|
|
if (
|
|
tp != tokenize.COMMENT or # skip non comments
|
|
not TYPE_COMMENT_RE.match(text) or # skip non-type comments
|
|
TYPE_IGNORE_RE.match(text) # skip ignores
|
|
):
|
|
continue
|
|
|
|
# search for the typeable node at or before the line number of the
|
|
# type comment.
|
|
# if the bisection insertion point is before any nodes this is an
|
|
# invalid type comment which is ignored.
|
|
lineno, _ = start
|
|
idx = bisect.bisect_right(visitor.typeable_lines, lineno)
|
|
if idx == 0:
|
|
continue
|
|
node = visitor.typeable_nodes[visitor.typeable_lines[idx - 1]]
|
|
type_comments[node].append((start, text))
|
|
|
|
return type_comments
|
|
|
|
|
|
class Checker(object):
|
|
"""
|
|
I check the cleanliness and sanity of Python code.
|
|
|
|
@ivar _deferredFunctions: Tracking list used by L{deferFunction}. Elements
|
|
of the list are two-tuples. The first element is the callable passed
|
|
to L{deferFunction}. The second element is a copy of the scope stack
|
|
at the time L{deferFunction} was called.
|
|
|
|
@ivar _deferredAssignments: Similar to C{_deferredFunctions}, but for
|
|
callables which are deferred assignment checks.
|
|
"""
|
|
|
|
_ast_node_scope = {
|
|
ast.Module: ModuleScope,
|
|
ast.ClassDef: ClassScope,
|
|
ast.FunctionDef: FunctionScope,
|
|
ast.Lambda: FunctionScope,
|
|
ast.ListComp: GeneratorScope,
|
|
ast.SetComp: GeneratorScope,
|
|
ast.GeneratorExp: GeneratorScope,
|
|
ast.DictComp: GeneratorScope,
|
|
}
|
|
if PY35_PLUS:
|
|
_ast_node_scope[ast.AsyncFunctionDef] = FunctionScope,
|
|
|
|
nodeDepth = 0
|
|
offset = None
|
|
traceTree = False
|
|
|
|
builtIns = set(builtin_vars).union(_MAGIC_GLOBALS)
|
|
_customBuiltIns = os.environ.get('PYFLAKES_BUILTINS')
|
|
if _customBuiltIns:
|
|
builtIns.update(_customBuiltIns.split(','))
|
|
del _customBuiltIns
|
|
|
|
# TODO: file_tokens= is required to perform checks on type comments,
|
|
# eventually make this a required positional argument. For now it
|
|
# is defaulted to `()` for api compatibility.
|
|
def __init__(self, tree, filename='(none)', builtins=None,
|
|
withDoctest='PYFLAKES_DOCTEST' in os.environ, file_tokens=()):
|
|
self._nodeHandlers = {}
|
|
self._deferredFunctions = []
|
|
self._deferredAssignments = []
|
|
self.deadScopes = []
|
|
self.messages = []
|
|
self.filename = filename
|
|
if builtins:
|
|
self.builtIns = self.builtIns.union(builtins)
|
|
self.withDoctest = withDoctest
|
|
try:
|
|
self.scopeStack = [Checker._ast_node_scope[type(tree)]()]
|
|
except KeyError:
|
|
raise RuntimeError('No scope implemented for the node %r' % tree)
|
|
self.exceptHandlers = [()]
|
|
self.root = tree
|
|
self._type_comments = _collect_type_comments(tree, file_tokens)
|
|
for builtin in self.builtIns:
|
|
self.addBinding(None, Builtin(builtin))
|
|
self.handleChildren(tree)
|
|
self.runDeferred(self._deferredFunctions)
|
|
# Set _deferredFunctions to None so that deferFunction will fail
|
|
# noisily if called after we've run through the deferred functions.
|
|
self._deferredFunctions = None
|
|
self.runDeferred(self._deferredAssignments)
|
|
# Set _deferredAssignments to None so that deferAssignment will fail
|
|
# noisily if called after we've run through the deferred assignments.
|
|
self._deferredAssignments = None
|
|
del self.scopeStack[1:]
|
|
self.popScope()
|
|
self.checkDeadScopes()
|
|
|
|
def deferFunction(self, callable):
|
|
"""
|
|
Schedule a function handler to be called just before completion.
|
|
|
|
This is used for handling function bodies, which must be deferred
|
|
because code later in the file might modify the global scope. When
|
|
`callable` is called, the scope at the time this is called will be
|
|
restored, however it will contain any new bindings added to it.
|
|
"""
|
|
self._deferredFunctions.append((callable, self.scopeStack[:], self.offset))
|
|
|
|
def deferAssignment(self, callable):
|
|
"""
|
|
Schedule an assignment handler to be called just after deferred
|
|
function handlers.
|
|
"""
|
|
self._deferredAssignments.append((callable, self.scopeStack[:], self.offset))
|
|
|
|
def runDeferred(self, deferred):
|
|
"""
|
|
Run the callables in C{deferred} using their associated scope stack.
|
|
"""
|
|
for handler, scope, offset in deferred:
|
|
self.scopeStack = scope
|
|
self.offset = offset
|
|
handler()
|
|
|
|
def _in_doctest(self):
|
|
return (len(self.scopeStack) >= 2 and
|
|
isinstance(self.scopeStack[1], DoctestScope))
|
|
|
|
@property
|
|
def futuresAllowed(self):
|
|
if not all(isinstance(scope, ModuleScope)
|
|
for scope in self.scopeStack):
|
|
return False
|
|
|
|
return self.scope._futures_allowed
|
|
|
|
@futuresAllowed.setter
|
|
def futuresAllowed(self, value):
|
|
assert value is False
|
|
if isinstance(self.scope, ModuleScope):
|
|
self.scope._futures_allowed = False
|
|
|
|
@property
|
|
def annotationsFutureEnabled(self):
|
|
scope = self.scopeStack[0]
|
|
if not isinstance(scope, ModuleScope):
|
|
return False
|
|
return scope._annotations_future_enabled
|
|
|
|
@annotationsFutureEnabled.setter
|
|
def annotationsFutureEnabled(self, value):
|
|
assert value is True
|
|
assert isinstance(self.scope, ModuleScope)
|
|
self.scope._annotations_future_enabled = True
|
|
|
|
@property
|
|
def scope(self):
|
|
return self.scopeStack[-1]
|
|
|
|
def popScope(self):
|
|
self.deadScopes.append(self.scopeStack.pop())
|
|
|
|
def checkDeadScopes(self):
|
|
"""
|
|
Look at scopes which have been fully examined and report names in them
|
|
which were imported but unused.
|
|
"""
|
|
for scope in self.deadScopes:
|
|
# imports in classes are public members
|
|
if isinstance(scope, ClassScope):
|
|
continue
|
|
|
|
all_binding = scope.get('__all__')
|
|
if all_binding and not isinstance(all_binding, ExportBinding):
|
|
all_binding = None
|
|
|
|
if all_binding:
|
|
all_names = set(all_binding.names)
|
|
undefined = all_names.difference(scope)
|
|
else:
|
|
all_names = undefined = []
|
|
|
|
if undefined:
|
|
if not scope.importStarred and \
|
|
os.path.basename(self.filename) != '__init__.py':
|
|
# Look for possible mistakes in the export list
|
|
for name in undefined:
|
|
self.report(messages.UndefinedExport,
|
|
scope['__all__'].source, name)
|
|
|
|
# mark all import '*' as used by the undefined in __all__
|
|
if scope.importStarred:
|
|
from_list = []
|
|
for binding in scope.values():
|
|
if isinstance(binding, StarImportation):
|
|
binding.used = all_binding
|
|
from_list.append(binding.fullName)
|
|
# report * usage, with a list of possible sources
|
|
from_list = ', '.join(sorted(from_list))
|
|
for name in undefined:
|
|
self.report(messages.ImportStarUsage,
|
|
scope['__all__'].source, name, from_list)
|
|
|
|
# Look for imported names that aren't used.
|
|
for value in scope.values():
|
|
if isinstance(value, Importation):
|
|
used = value.used or value.name in all_names
|
|
if not used:
|
|
messg = messages.UnusedImport
|
|
self.report(messg, value.source, str(value))
|
|
for node in value.redefined:
|
|
if isinstance(self.getParent(node), FOR_TYPES):
|
|
messg = messages.ImportShadowedByLoopVar
|
|
elif used:
|
|
continue
|
|
else:
|
|
messg = messages.RedefinedWhileUnused
|
|
self.report(messg, node, value.name, value.source)
|
|
|
|
def pushScope(self, scopeClass=FunctionScope):
|
|
self.scopeStack.append(scopeClass())
|
|
|
|
def report(self, messageClass, *args, **kwargs):
|
|
self.messages.append(messageClass(self.filename, *args, **kwargs))
|
|
|
|
def getParent(self, node):
|
|
# Lookup the first parent which is not Tuple, List or Starred
|
|
while True:
|
|
node = node.parent
|
|
if not hasattr(node, 'elts') and not hasattr(node, 'ctx'):
|
|
return node
|
|
|
|
def getCommonAncestor(self, lnode, rnode, stop):
|
|
if stop in (lnode, rnode) or not (hasattr(lnode, 'parent') and
|
|
hasattr(rnode, 'parent')):
|
|
return None
|
|
if lnode is rnode:
|
|
return lnode
|
|
|
|
if (lnode.depth > rnode.depth):
|
|
return self.getCommonAncestor(lnode.parent, rnode, stop)
|
|
if (lnode.depth < rnode.depth):
|
|
return self.getCommonAncestor(lnode, rnode.parent, stop)
|
|
return self.getCommonAncestor(lnode.parent, rnode.parent, stop)
|
|
|
|
def descendantOf(self, node, ancestors, stop):
|
|
for a in ancestors:
|
|
if self.getCommonAncestor(node, a, stop):
|
|
return True
|
|
return False
|
|
|
|
def _getAncestor(self, node, ancestor_type):
|
|
parent = node
|
|
while True:
|
|
if parent is self.root:
|
|
return None
|
|
parent = self.getParent(parent)
|
|
if isinstance(parent, ancestor_type):
|
|
return parent
|
|
|
|
def getScopeNode(self, node):
|
|
return self._getAncestor(node, tuple(Checker._ast_node_scope.keys()))
|
|
|
|
def differentForks(self, lnode, rnode):
|
|
"""True, if lnode and rnode are located on different forks of IF/TRY"""
|
|
ancestor = self.getCommonAncestor(lnode, rnode, self.root)
|
|
parts = getAlternatives(ancestor)
|
|
if parts:
|
|
for items in parts:
|
|
if self.descendantOf(lnode, items, ancestor) ^ \
|
|
self.descendantOf(rnode, items, ancestor):
|
|
return True
|
|
return False
|
|
|
|
def addBinding(self, node, value):
|
|
"""
|
|
Called when a binding is altered.
|
|
|
|
- `node` is the statement responsible for the change
|
|
- `value` is the new value, a Binding instance
|
|
"""
|
|
# assert value.source in (node, node.parent):
|
|
for scope in self.scopeStack[::-1]:
|
|
if value.name in scope:
|
|
break
|
|
existing = scope.get(value.name)
|
|
|
|
if (existing and not isinstance(existing, Builtin) and
|
|
not self.differentForks(node, existing.source)):
|
|
|
|
parent_stmt = self.getParent(value.source)
|
|
if isinstance(existing, Importation) and isinstance(parent_stmt, FOR_TYPES):
|
|
self.report(messages.ImportShadowedByLoopVar,
|
|
node, value.name, existing.source)
|
|
|
|
elif scope is self.scope:
|
|
if (isinstance(parent_stmt, ast.comprehension) and
|
|
not isinstance(self.getParent(existing.source),
|
|
(FOR_TYPES, ast.comprehension))):
|
|
self.report(messages.RedefinedInListComp,
|
|
node, value.name, existing.source)
|
|
elif not existing.used and value.redefines(existing):
|
|
if value.name != '_' or isinstance(existing, Importation):
|
|
if not is_typing_overload(existing, self.scope):
|
|
self.report(messages.RedefinedWhileUnused,
|
|
node, value.name, existing.source)
|
|
|
|
elif isinstance(existing, Importation) and value.redefines(existing):
|
|
existing.redefined.append(node)
|
|
|
|
if value.name in self.scope:
|
|
# then assume the rebound name is used as a global or within a loop
|
|
value.used = self.scope[value.name].used
|
|
|
|
self.scope[value.name] = value
|
|
|
|
def getNodeHandler(self, node_class):
|
|
try:
|
|
return self._nodeHandlers[node_class]
|
|
except KeyError:
|
|
nodeType = getNodeType(node_class)
|
|
self._nodeHandlers[node_class] = handler = getattr(self, nodeType)
|
|
return handler
|
|
|
|
def handleNodeLoad(self, node):
|
|
name = getNodeName(node)
|
|
if not name:
|
|
return
|
|
|
|
in_generators = None
|
|
importStarred = None
|
|
|
|
# try enclosing function scopes and global scope
|
|
for scope in self.scopeStack[-1::-1]:
|
|
if isinstance(scope, ClassScope):
|
|
if not PY2 and name == '__class__':
|
|
return
|
|
elif in_generators is False:
|
|
# only generators used in a class scope can access the
|
|
# names of the class. this is skipped during the first
|
|
# iteration
|
|
continue
|
|
|
|
if (name == 'print' and
|
|
isinstance(scope.get(name, None), Builtin)):
|
|
parent = self.getParent(node)
|
|
if (isinstance(parent, ast.BinOp) and
|
|
isinstance(parent.op, ast.RShift)):
|
|
self.report(messages.InvalidPrintSyntax, node)
|
|
|
|
try:
|
|
scope[name].used = (self.scope, node)
|
|
|
|
# if the name of SubImportation is same as
|
|
# alias of other Importation and the alias
|
|
# is used, SubImportation also should be marked as used.
|
|
n = scope[name]
|
|
if isinstance(n, Importation) and n._has_alias():
|
|
try:
|
|
scope[n.fullName].used = (self.scope, node)
|
|
except KeyError:
|
|
pass
|
|
except KeyError:
|
|
pass
|
|
else:
|
|
return
|
|
|
|
importStarred = importStarred or scope.importStarred
|
|
|
|
if in_generators is not False:
|
|
in_generators = isinstance(scope, GeneratorScope)
|
|
|
|
if importStarred:
|
|
from_list = []
|
|
|
|
for scope in self.scopeStack[-1::-1]:
|
|
for binding in scope.values():
|
|
if isinstance(binding, StarImportation):
|
|
# mark '*' imports as used for each scope
|
|
binding.used = (self.scope, node)
|
|
from_list.append(binding.fullName)
|
|
|
|
# report * usage, with a list of possible sources
|
|
from_list = ', '.join(sorted(from_list))
|
|
self.report(messages.ImportStarUsage, node, name, from_list)
|
|
return
|
|
|
|
if name == '__path__' and os.path.basename(self.filename) == '__init__.py':
|
|
# the special name __path__ is valid only in packages
|
|
return
|
|
|
|
if name == '__module__' and isinstance(self.scope, ClassScope):
|
|
return
|
|
|
|
# protected with a NameError handler?
|
|
if 'NameError' not in self.exceptHandlers[-1]:
|
|
self.report(messages.UndefinedName, node, name)
|
|
|
|
def handleNodeStore(self, node):
|
|
name = getNodeName(node)
|
|
if not name:
|
|
return
|
|
# if the name hasn't already been defined in the current scope
|
|
if isinstance(self.scope, FunctionScope) and name not in self.scope:
|
|
# for each function or module scope above us
|
|
for scope in self.scopeStack[:-1]:
|
|
if not isinstance(scope, (FunctionScope, ModuleScope)):
|
|
continue
|
|
# if the name was defined in that scope, and the name has
|
|
# been accessed already in the current scope, and hasn't
|
|
# been declared global
|
|
used = name in scope and scope[name].used
|
|
if used and used[0] is self.scope and name not in self.scope.globals:
|
|
# then it's probably a mistake
|
|
self.report(messages.UndefinedLocal,
|
|
scope[name].used[1], name, scope[name].source)
|
|
break
|
|
|
|
parent_stmt = self.getParent(node)
|
|
if isinstance(parent_stmt, (FOR_TYPES, ast.comprehension)) or (
|
|
parent_stmt != node.parent and
|
|
not self.isLiteralTupleUnpacking(parent_stmt)):
|
|
binding = Binding(name, node)
|
|
elif name == '__all__' and isinstance(self.scope, ModuleScope):
|
|
binding = ExportBinding(name, node.parent, self.scope)
|
|
elif isinstance(getattr(node, 'ctx', None), ast.Param):
|
|
binding = Argument(name, self.getScopeNode(node))
|
|
else:
|
|
binding = Assignment(name, node)
|
|
self.addBinding(node, binding)
|
|
|
|
def handleNodeDelete(self, node):
|
|
|
|
def on_conditional_branch():
|
|
"""
|
|
Return `True` if node is part of a conditional body.
|
|
"""
|
|
current = getattr(node, 'parent', None)
|
|
while current:
|
|
if isinstance(current, (ast.If, ast.While, ast.IfExp)):
|
|
return True
|
|
current = getattr(current, 'parent', None)
|
|
return False
|
|
|
|
name = getNodeName(node)
|
|
if not name:
|
|
return
|
|
|
|
if on_conditional_branch():
|
|
# We cannot predict if this conditional branch is going to
|
|
# be executed.
|
|
return
|
|
|
|
if isinstance(self.scope, FunctionScope) and name in self.scope.globals:
|
|
self.scope.globals.remove(name)
|
|
else:
|
|
try:
|
|
del self.scope[name]
|
|
except KeyError:
|
|
self.report(messages.UndefinedName, node, name)
|
|
|
|
def _handle_type_comments(self, node):
|
|
for (lineno, col_offset), comment in self._type_comments.get(node, ()):
|
|
comment = comment.split(':', 1)[1].strip()
|
|
func_match = TYPE_FUNC_RE.match(comment)
|
|
if func_match:
|
|
parts = (
|
|
func_match.group(1).replace('*', ''),
|
|
func_match.group(2).strip(),
|
|
)
|
|
else:
|
|
parts = (comment,)
|
|
|
|
for part in parts:
|
|
if PY2:
|
|
part = part.replace('...', 'Ellipsis')
|
|
self.deferFunction(functools.partial(
|
|
self.handleStringAnnotation,
|
|
part, DummyNode(lineno, col_offset), lineno, col_offset,
|
|
messages.CommentAnnotationSyntaxError,
|
|
))
|
|
|
|
def handleChildren(self, tree, omit=None):
|
|
self._handle_type_comments(tree)
|
|
for node in iter_child_nodes(tree, omit=omit):
|
|
self.handleNode(node, tree)
|
|
|
|
def isLiteralTupleUnpacking(self, node):
|
|
if isinstance(node, ast.Assign):
|
|
for child in node.targets + [node.value]:
|
|
if not hasattr(child, 'elts'):
|
|
return False
|
|
return True
|
|
|
|
def isDocstring(self, node):
|
|
"""
|
|
Determine if the given node is a docstring, as long as it is at the
|
|
correct place in the node tree.
|
|
"""
|
|
return isinstance(node, ast.Str) or (isinstance(node, ast.Expr) and
|
|
isinstance(node.value, ast.Str))
|
|
|
|
def getDocstring(self, node):
|
|
if isinstance(node, ast.Expr):
|
|
node = node.value
|
|
if not isinstance(node, ast.Str):
|
|
return (None, None)
|
|
|
|
if PYPY or PY38_PLUS:
|
|
doctest_lineno = node.lineno - 1
|
|
else:
|
|
# Computed incorrectly if the docstring has backslash
|
|
doctest_lineno = node.lineno - node.s.count('\n') - 1
|
|
|
|
return (node.s, doctest_lineno)
|
|
|
|
def handleNode(self, node, parent):
|
|
if node is None:
|
|
return
|
|
if self.offset and getattr(node, 'lineno', None) is not None:
|
|
node.lineno += self.offset[0]
|
|
node.col_offset += self.offset[1]
|
|
if self.traceTree:
|
|
print(' ' * self.nodeDepth + node.__class__.__name__)
|
|
if self.futuresAllowed and not (isinstance(node, ast.ImportFrom) or
|
|
self.isDocstring(node)):
|
|
self.futuresAllowed = False
|
|
self.nodeDepth += 1
|
|
node.depth = self.nodeDepth
|
|
node.parent = parent
|
|
try:
|
|
handler = self.getNodeHandler(node.__class__)
|
|
handler(node)
|
|
finally:
|
|
self.nodeDepth -= 1
|
|
if self.traceTree:
|
|
print(' ' * self.nodeDepth + 'end ' + node.__class__.__name__)
|
|
|
|
_getDoctestExamples = doctest.DocTestParser().get_examples
|
|
|
|
def handleDoctests(self, node):
|
|
try:
|
|
if hasattr(node, 'docstring'):
|
|
docstring = node.docstring
|
|
|
|
# This is just a reasonable guess. In Python 3.7, docstrings no
|
|
# longer have line numbers associated with them. This will be
|
|
# incorrect if there are empty lines between the beginning
|
|
# of the function and the docstring.
|
|
node_lineno = node.lineno
|
|
if hasattr(node, 'args'):
|
|
node_lineno = max([node_lineno] +
|
|
[arg.lineno for arg in node.args.args])
|
|
else:
|
|
(docstring, node_lineno) = self.getDocstring(node.body[0])
|
|
examples = docstring and self._getDoctestExamples(docstring)
|
|
except (ValueError, IndexError):
|
|
# e.g. line 6 of the docstring for <string> has inconsistent
|
|
# leading whitespace: ...
|
|
return
|
|
if not examples:
|
|
return
|
|
|
|
# Place doctest in module scope
|
|
saved_stack = self.scopeStack
|
|
self.scopeStack = [self.scopeStack[0]]
|
|
node_offset = self.offset or (0, 0)
|
|
self.pushScope(DoctestScope)
|
|
self.addBinding(None, Builtin('_'))
|
|
for example in examples:
|
|
try:
|
|
tree = ast.parse(example.source, "<doctest>")
|
|
except SyntaxError:
|
|
e = sys.exc_info()[1]
|
|
if PYPY:
|
|
e.offset += 1
|
|
position = (node_lineno + example.lineno + e.lineno,
|
|
example.indent + 4 + (e.offset or 0))
|
|
self.report(messages.DoctestSyntaxError, node, position)
|
|
else:
|
|
self.offset = (node_offset[0] + node_lineno + example.lineno,
|
|
node_offset[1] + example.indent + 4)
|
|
self.handleChildren(tree)
|
|
self.offset = node_offset
|
|
self.popScope()
|
|
self.scopeStack = saved_stack
|
|
|
|
def handleStringAnnotation(self, s, node, ref_lineno, ref_col_offset, err):
|
|
try:
|
|
tree = ast.parse(s)
|
|
except SyntaxError:
|
|
self.report(err, node, s)
|
|
return
|
|
|
|
body = tree.body
|
|
if len(body) != 1 or not isinstance(body[0], ast.Expr):
|
|
self.report(err, node, s)
|
|
return
|
|
|
|
parsed_annotation = tree.body[0].value
|
|
for descendant in ast.walk(parsed_annotation):
|
|
if (
|
|
'lineno' in descendant._attributes and
|
|
'col_offset' in descendant._attributes
|
|
):
|
|
descendant.lineno = ref_lineno
|
|
descendant.col_offset = ref_col_offset
|
|
|
|
self.handleNode(parsed_annotation, node)
|
|
|
|
def handleAnnotation(self, annotation, node):
|
|
if isinstance(annotation, ast.Str):
|
|
# Defer handling forward annotation.
|
|
self.deferFunction(functools.partial(
|
|
self.handleStringAnnotation,
|
|
annotation.s,
|
|
node,
|
|
annotation.lineno,
|
|
annotation.col_offset,
|
|
messages.ForwardAnnotationSyntaxError,
|
|
))
|
|
elif self.annotationsFutureEnabled:
|
|
self.deferFunction(lambda: self.handleNode(annotation, node))
|
|
else:
|
|
self.handleNode(annotation, node)
|
|
|
|
def ignore(self, node):
|
|
pass
|
|
|
|
# "stmt" type nodes
|
|
DELETE = PRINT = FOR = ASYNCFOR = WHILE = IF = WITH = WITHITEM = \
|
|
ASYNCWITH = ASYNCWITHITEM = TRYFINALLY = EXEC = \
|
|
EXPR = ASSIGN = handleChildren
|
|
|
|
PASS = ignore
|
|
|
|
# "expr" type nodes
|
|
BOOLOP = BINOP = UNARYOP = IFEXP = SET = \
|
|
CALL = REPR = ATTRIBUTE = SUBSCRIPT = \
|
|
STARRED = NAMECONSTANT = handleChildren
|
|
|
|
NUM = STR = BYTES = ELLIPSIS = CONSTANT = ignore
|
|
|
|
# "slice" type nodes
|
|
SLICE = EXTSLICE = INDEX = handleChildren
|
|
|
|
# expression contexts are node instances too, though being constants
|
|
LOAD = STORE = DEL = AUGLOAD = AUGSTORE = PARAM = ignore
|
|
|
|
# same for operators
|
|
AND = OR = ADD = SUB = MULT = DIV = MOD = POW = LSHIFT = RSHIFT = \
|
|
BITOR = BITXOR = BITAND = FLOORDIV = INVERT = NOT = UADD = USUB = \
|
|
EQ = NOTEQ = LT = LTE = GT = GTE = IS = ISNOT = IN = NOTIN = \
|
|
MATMULT = ignore
|
|
|
|
def RAISE(self, node):
|
|
self.handleChildren(node)
|
|
|
|
arg = get_raise_argument(node)
|
|
|
|
if isinstance(arg, ast.Call):
|
|
if is_notimplemented_name_node(arg.func):
|
|
# Handle "raise NotImplemented(...)"
|
|
self.report(messages.RaiseNotImplemented, node)
|
|
elif is_notimplemented_name_node(arg):
|
|
# Handle "raise NotImplemented"
|
|
self.report(messages.RaiseNotImplemented, node)
|
|
|
|
# additional node types
|
|
COMPREHENSION = KEYWORD = FORMATTEDVALUE = JOINEDSTR = handleChildren
|
|
|
|
def DICT(self, node):
|
|
# Complain if there are duplicate keys with different values
|
|
# If they have the same value it's not going to cause potentially
|
|
# unexpected behaviour so we'll not complain.
|
|
keys = [
|
|
convert_to_value(key) for key in node.keys
|
|
]
|
|
|
|
key_counts = counter(keys)
|
|
duplicate_keys = [
|
|
key for key, count in key_counts.items()
|
|
if count > 1
|
|
]
|
|
|
|
for key in duplicate_keys:
|
|
key_indices = [i for i, i_key in enumerate(keys) if i_key == key]
|
|
|
|
values = counter(
|
|
convert_to_value(node.values[index])
|
|
for index in key_indices
|
|
)
|
|
if any(count == 1 for value, count in values.items()):
|
|
for key_index in key_indices:
|
|
key_node = node.keys[key_index]
|
|
if isinstance(key, VariableKey):
|
|
self.report(messages.MultiValueRepeatedKeyVariable,
|
|
key_node,
|
|
key.name)
|
|
else:
|
|
self.report(
|
|
messages.MultiValueRepeatedKeyLiteral,
|
|
key_node,
|
|
key,
|
|
)
|
|
self.handleChildren(node)
|
|
|
|
def ASSERT(self, node):
|
|
if isinstance(node.test, ast.Tuple) and node.test.elts != []:
|
|
self.report(messages.AssertTuple, node)
|
|
self.handleChildren(node)
|
|
|
|
def GLOBAL(self, node):
|
|
"""
|
|
Keep track of globals declarations.
|
|
"""
|
|
global_scope_index = 1 if self._in_doctest() else 0
|
|
global_scope = self.scopeStack[global_scope_index]
|
|
|
|
# Ignore 'global' statement in global scope.
|
|
if self.scope is not global_scope:
|
|
|
|
# One 'global' statement can bind multiple (comma-delimited) names.
|
|
for node_name in node.names:
|
|
node_value = Assignment(node_name, node)
|
|
|
|
# Remove UndefinedName messages already reported for this name.
|
|
# TODO: if the global is not used in this scope, it does not
|
|
# become a globally defined name. See test_unused_global.
|
|
self.messages = [
|
|
m for m in self.messages if not
|
|
isinstance(m, messages.UndefinedName) or
|
|
m.message_args[0] != node_name]
|
|
|
|
# Bind name to global scope if it doesn't exist already.
|
|
global_scope.setdefault(node_name, node_value)
|
|
|
|
# Bind name to non-global scopes, but as already "used".
|
|
node_value.used = (global_scope, node)
|
|
for scope in self.scopeStack[global_scope_index + 1:]:
|
|
scope[node_name] = node_value
|
|
|
|
NONLOCAL = GLOBAL
|
|
|
|
def GENERATOREXP(self, node):
|
|
self.pushScope(GeneratorScope)
|
|
self.handleChildren(node)
|
|
self.popScope()
|
|
|
|
LISTCOMP = handleChildren if PY2 else GENERATOREXP
|
|
|
|
DICTCOMP = SETCOMP = GENERATOREXP
|
|
|
|
def NAME(self, node):
|
|
"""
|
|
Handle occurrence of Name (which can be a load/store/delete access.)
|
|
"""
|
|
# Locate the name in locals / function / globals scopes.
|
|
if isinstance(node.ctx, (ast.Load, ast.AugLoad)):
|
|
self.handleNodeLoad(node)
|
|
if (node.id == 'locals' and isinstance(self.scope, FunctionScope) and
|
|
isinstance(node.parent, ast.Call)):
|
|
# we are doing locals() call in current scope
|
|
self.scope.usesLocals = True
|
|
elif isinstance(node.ctx, (ast.Store, ast.AugStore, ast.Param)):
|
|
self.handleNodeStore(node)
|
|
elif isinstance(node.ctx, ast.Del):
|
|
self.handleNodeDelete(node)
|
|
else:
|
|
# Unknown context
|
|
raise RuntimeError("Got impossible expression context: %r" % (node.ctx,))
|
|
|
|
def CONTINUE(self, node):
|
|
# Walk the tree up until we see a loop (OK), a function or class
|
|
# definition (not OK), for 'continue', a finally block (not OK), or
|
|
# the top module scope (not OK)
|
|
n = node
|
|
while hasattr(n, 'parent'):
|
|
n, n_child = n.parent, n
|
|
if isinstance(n, LOOP_TYPES):
|
|
# Doesn't apply unless it's in the loop itself
|
|
if n_child not in n.orelse:
|
|
return
|
|
if isinstance(n, (ast.FunctionDef, ast.ClassDef)):
|
|
break
|
|
# Handle Try/TryFinally difference in Python < and >= 3.3
|
|
if hasattr(n, 'finalbody') and isinstance(node, ast.Continue):
|
|
if n_child in n.finalbody:
|
|
self.report(messages.ContinueInFinally, node)
|
|
return
|
|
if isinstance(node, ast.Continue):
|
|
self.report(messages.ContinueOutsideLoop, node)
|
|
else: # ast.Break
|
|
self.report(messages.BreakOutsideLoop, node)
|
|
|
|
BREAK = CONTINUE
|
|
|
|
def RETURN(self, node):
|
|
if isinstance(self.scope, (ClassScope, ModuleScope)):
|
|
self.report(messages.ReturnOutsideFunction, node)
|
|
return
|
|
|
|
if (
|
|
node.value and
|
|
hasattr(self.scope, 'returnValue') and
|
|
not self.scope.returnValue
|
|
):
|
|
self.scope.returnValue = node.value
|
|
self.handleNode(node.value, node)
|
|
|
|
def YIELD(self, node):
|
|
if isinstance(self.scope, (ClassScope, ModuleScope)):
|
|
self.report(messages.YieldOutsideFunction, node)
|
|
return
|
|
|
|
self.scope.isGenerator = True
|
|
self.handleNode(node.value, node)
|
|
|
|
AWAIT = YIELDFROM = YIELD
|
|
|
|
def FUNCTIONDEF(self, node):
|
|
for deco in node.decorator_list:
|
|
self.handleNode(deco, node)
|
|
self.LAMBDA(node)
|
|
self.addBinding(node, FunctionDefinition(node.name, node))
|
|
# doctest does not process doctest within a doctest,
|
|
# or in nested functions.
|
|
if (self.withDoctest and
|
|
not self._in_doctest() and
|
|
not isinstance(self.scope, FunctionScope)):
|
|
self.deferFunction(lambda: self.handleDoctests(node))
|
|
|
|
ASYNCFUNCTIONDEF = FUNCTIONDEF
|
|
|
|
def LAMBDA(self, node):
|
|
args = []
|
|
annotations = []
|
|
|
|
if PY2:
|
|
def addArgs(arglist):
|
|
for arg in arglist:
|
|
if isinstance(arg, ast.Tuple):
|
|
addArgs(arg.elts)
|
|
else:
|
|
args.append(arg.id)
|
|
addArgs(node.args.args)
|
|
defaults = node.args.defaults
|
|
else:
|
|
for arg in node.args.args + node.args.kwonlyargs:
|
|
args.append(arg.arg)
|
|
annotations.append(arg.annotation)
|
|
defaults = node.args.defaults + node.args.kw_defaults
|
|
|
|
# Only for Python3 FunctionDefs
|
|
is_py3_func = hasattr(node, 'returns')
|
|
|
|
for arg_name in ('vararg', 'kwarg'):
|
|
wildcard = getattr(node.args, arg_name)
|
|
if not wildcard:
|
|
continue
|
|
args.append(wildcard if PY2 else wildcard.arg)
|
|
if is_py3_func:
|
|
if PY2: # Python 2.7
|
|
argannotation = arg_name + 'annotation'
|
|
annotations.append(getattr(node.args, argannotation))
|
|
else: # Python >= 3.4
|
|
annotations.append(wildcard.annotation)
|
|
|
|
if is_py3_func:
|
|
annotations.append(node.returns)
|
|
|
|
if len(set(args)) < len(args):
|
|
for (idx, arg) in enumerate(args):
|
|
if arg in args[:idx]:
|
|
self.report(messages.DuplicateArgument, node, arg)
|
|
|
|
for annotation in annotations:
|
|
self.handleAnnotation(annotation, node)
|
|
|
|
for default in defaults:
|
|
self.handleNode(default, node)
|
|
|
|
def runFunction():
|
|
|
|
self.pushScope()
|
|
|
|
self.handleChildren(node, omit='decorator_list')
|
|
|
|
def checkUnusedAssignments():
|
|
"""
|
|
Check to see if any assignments have not been used.
|
|
"""
|
|
for name, binding in self.scope.unusedAssignments():
|
|
self.report(messages.UnusedVariable, binding.source, name)
|
|
self.deferAssignment(checkUnusedAssignments)
|
|
|
|
if PY2:
|
|
def checkReturnWithArgumentInsideGenerator():
|
|
"""
|
|
Check to see if there is any return statement with
|
|
arguments but the function is a generator.
|
|
"""
|
|
if self.scope.isGenerator and self.scope.returnValue:
|
|
self.report(messages.ReturnWithArgsInsideGenerator,
|
|
self.scope.returnValue)
|
|
self.deferAssignment(checkReturnWithArgumentInsideGenerator)
|
|
self.popScope()
|
|
|
|
self.deferFunction(runFunction)
|
|
|
|
def ARGUMENTS(self, node):
|
|
self.handleChildren(node, omit=('defaults', 'kw_defaults'))
|
|
if PY2:
|
|
scope_node = self.getScopeNode(node)
|
|
if node.vararg:
|
|
self.addBinding(node, Argument(node.vararg, scope_node))
|
|
if node.kwarg:
|
|
self.addBinding(node, Argument(node.kwarg, scope_node))
|
|
|
|
def ARG(self, node):
|
|
self.addBinding(node, Argument(node.arg, self.getScopeNode(node)))
|
|
|
|
def CLASSDEF(self, node):
|
|
"""
|
|
Check names used in a class definition, including its decorators, base
|
|
classes, and the body of its definition. Additionally, add its name to
|
|
the current scope.
|
|
"""
|
|
for deco in node.decorator_list:
|
|
self.handleNode(deco, node)
|
|
for baseNode in node.bases:
|
|
self.handleNode(baseNode, node)
|
|
if not PY2:
|
|
for keywordNode in node.keywords:
|
|
self.handleNode(keywordNode, node)
|
|
self.pushScope(ClassScope)
|
|
# doctest does not process doctest within a doctest
|
|
# classes within classes are processed.
|
|
if (self.withDoctest and
|
|
not self._in_doctest() and
|
|
not isinstance(self.scope, FunctionScope)):
|
|
self.deferFunction(lambda: self.handleDoctests(node))
|
|
for stmt in node.body:
|
|
self.handleNode(stmt, node)
|
|
self.popScope()
|
|
self.addBinding(node, ClassDefinition(node.name, node))
|
|
|
|
def AUGASSIGN(self, node):
|
|
self.handleNodeLoad(node.target)
|
|
self.handleNode(node.value, node)
|
|
self.handleNode(node.target, node)
|
|
|
|
def TUPLE(self, node):
|
|
if not PY2 and isinstance(node.ctx, ast.Store):
|
|
# Python 3 advanced tuple unpacking: a, *b, c = d.
|
|
# Only one starred expression is allowed, and no more than 1<<8
|
|
# assignments are allowed before a stared expression. There is
|
|
# also a limit of 1<<24 expressions after the starred expression,
|
|
# which is impossible to test due to memory restrictions, but we
|
|
# add it here anyway
|
|
has_starred = False
|
|
star_loc = -1
|
|
for i, n in enumerate(node.elts):
|
|
if isinstance(n, ast.Starred):
|
|
if has_starred:
|
|
self.report(messages.TwoStarredExpressions, node)
|
|
# The SyntaxError doesn't distinguish two from more
|
|
# than two.
|
|
break
|
|
has_starred = True
|
|
star_loc = i
|
|
if star_loc >= 1 << 8 or len(node.elts) - star_loc - 1 >= 1 << 24:
|
|
self.report(messages.TooManyExpressionsInStarredAssignment, node)
|
|
self.handleChildren(node)
|
|
|
|
LIST = TUPLE
|
|
|
|
def IMPORT(self, node):
|
|
for alias in node.names:
|
|
if '.' in alias.name and not alias.asname:
|
|
importation = SubmoduleImportation(alias.name, node)
|
|
else:
|
|
name = alias.asname or alias.name
|
|
importation = Importation(name, node, alias.name)
|
|
self.addBinding(node, importation)
|
|
|
|
def IMPORTFROM(self, node):
|
|
if node.module == '__future__':
|
|
if not self.futuresAllowed:
|
|
self.report(messages.LateFutureImport,
|
|
node, [n.name for n in node.names])
|
|
else:
|
|
self.futuresAllowed = False
|
|
|
|
module = ('.' * node.level) + (node.module or '')
|
|
|
|
for alias in node.names:
|
|
name = alias.asname or alias.name
|
|
if node.module == '__future__':
|
|
importation = FutureImportation(name, node, self.scope)
|
|
if alias.name not in __future__.all_feature_names:
|
|
self.report(messages.FutureFeatureNotDefined,
|
|
node, alias.name)
|
|
if alias.name == 'annotations':
|
|
self.annotationsFutureEnabled = True
|
|
elif alias.name == '*':
|
|
# Only Python 2, local import * is a SyntaxWarning
|
|
if not PY2 and not isinstance(self.scope, ModuleScope):
|
|
self.report(messages.ImportStarNotPermitted,
|
|
node, module)
|
|
continue
|
|
|
|
self.scope.importStarred = True
|
|
self.report(messages.ImportStarUsed, node, module)
|
|
importation = StarImportation(module, node)
|
|
else:
|
|
importation = ImportationFrom(name, node,
|
|
module, alias.name)
|
|
self.addBinding(node, importation)
|
|
|
|
def TRY(self, node):
|
|
handler_names = []
|
|
# List the exception handlers
|
|
for i, handler in enumerate(node.handlers):
|
|
if isinstance(handler.type, ast.Tuple):
|
|
for exc_type in handler.type.elts:
|
|
handler_names.append(getNodeName(exc_type))
|
|
elif handler.type:
|
|
handler_names.append(getNodeName(handler.type))
|
|
|
|
if handler.type is None and i < len(node.handlers) - 1:
|
|
self.report(messages.DefaultExceptNotLast, handler)
|
|
# Memorize the except handlers and process the body
|
|
self.exceptHandlers.append(handler_names)
|
|
for child in node.body:
|
|
self.handleNode(child, node)
|
|
self.exceptHandlers.pop()
|
|
# Process the other nodes: "except:", "else:", "finally:"
|
|
self.handleChildren(node, omit='body')
|
|
|
|
TRYEXCEPT = TRY
|
|
|
|
def EXCEPTHANDLER(self, node):
|
|
if PY2 or node.name is None:
|
|
self.handleChildren(node)
|
|
return
|
|
|
|
# If the name already exists in the scope, modify state of existing
|
|
# binding.
|
|
if node.name in self.scope:
|
|
self.handleNodeStore(node)
|
|
|
|
# 3.x: the name of the exception, which is not a Name node, but a
|
|
# simple string, creates a local that is only bound within the scope of
|
|
# the except: block. As such, temporarily remove the existing binding
|
|
# to more accurately determine if the name is used in the except:
|
|
# block.
|
|
|
|
try:
|
|
prev_definition = self.scope.pop(node.name)
|
|
except KeyError:
|
|
prev_definition = None
|
|
|
|
self.handleNodeStore(node)
|
|
self.handleChildren(node)
|
|
|
|
# See discussion on https://github.com/PyCQA/pyflakes/pull/59
|
|
|
|
# We're removing the local name since it's being unbound after leaving
|
|
# the except: block and it's always unbound if the except: block is
|
|
# never entered. This will cause an "undefined name" error raised if
|
|
# the checked code tries to use the name afterwards.
|
|
#
|
|
# Unless it's been removed already. Then do nothing.
|
|
|
|
try:
|
|
binding = self.scope.pop(node.name)
|
|
except KeyError:
|
|
pass
|
|
else:
|
|
if not binding.used:
|
|
self.report(messages.UnusedVariable, node, node.name)
|
|
|
|
# Restore.
|
|
if prev_definition:
|
|
self.scope[node.name] = prev_definition
|
|
|
|
def ANNASSIGN(self, node):
|
|
if node.value:
|
|
# Only bind the *targets* if the assignment has a value.
|
|
# Otherwise it's not really ast.Store and shouldn't silence
|
|
# UndefinedLocal warnings.
|
|
self.handleNode(node.target, node)
|
|
self.handleAnnotation(node.annotation, node)
|
|
if node.value:
|
|
# If the assignment has value, handle the *value* now.
|
|
self.handleNode(node.value, node)
|
|
|
|
def COMPARE(self, node):
|
|
literals = (ast.Str, ast.Num)
|
|
if not PY2:
|
|
literals += (ast.Bytes,)
|
|
|
|
left = node.left
|
|
for op, right in zip(node.ops, node.comparators):
|
|
if (isinstance(op, (ast.Is, ast.IsNot)) and
|
|
(isinstance(left, literals) or isinstance(right, literals))):
|
|
self.report(messages.IsLiteral, node)
|
|
left = right
|
|
|
|
self.handleChildren(node)
|