926 lines
33 KiB
Python
926 lines
33 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 doctest
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import os
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import sys
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PY2 = sys.version_info < (3, 0)
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PY32 = sys.version_info < (3, 3) # Python 2.5 to 3.2
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PY33 = sys.version_info < (3, 4) # Python 2.5 to 3.3
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builtin_vars = dir(__import__('__builtin__' if PY2 else 'builtins'))
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try:
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import ast
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except ImportError: # Python 2.5
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import _ast as ast
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if 'decorator_list' not in ast.ClassDef._fields:
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# Patch the missing attribute 'decorator_list'
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ast.ClassDef.decorator_list = ()
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ast.FunctionDef.decorator_list = property(lambda s: s.decorators)
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from pyflakes import messages
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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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else:
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def getNodeType(node_class):
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return node_class.__name__.upper()
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# Python >= 3.3 uses ast.Try instead of (ast.TryExcept + ast.TryFinally)
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if PY32:
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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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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 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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"""
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for name in _fields_order[node.__class__]:
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if name == 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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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}, line-number) indicating the scope and
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line number 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 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):
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self.fullName = name
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self.redefined = []
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name = name.split('.')[0]
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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, Importation):
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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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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 C{__all__} assignment that can be recognized is one which takes
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the value of a literal list containing literal strings. For example::
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__all__ = ["foo", "bar"]
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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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if isinstance(source.value, (ast.List, ast.Tuple)):
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for node in source.value.elts:
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if isinstance(node, ast.Str):
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self.names.append(node.s)
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super(ExportBinding, self).__init__(name, source)
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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 = set(['__tracebackhide__',
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'__traceback_info__', '__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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"""
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Return a generator for the assignments which have not been used.
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"""
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for name, binding in self.items():
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if (not binding.used and name not in self.globals
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and not self.usesLocals
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and 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):
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pass
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# Globally defined names which are not attributes of the builtins module, or
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# are only present on some platforms.
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_MAGIC_GLOBALS = ['__file__', '__builtins__', 'WindowsError']
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def getNodeName(node):
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# Returns node.id, or node.name, or None
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if hasattr(node, 'id'): # One of the many nodes with an id
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return node.id
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if hasattr(node, 'name'): # a ExceptHandler node
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return node.name
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class Checker(object):
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"""
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I check the cleanliness and sanity of Python code.
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@ivar _deferredFunctions: Tracking list used by L{deferFunction}. Elements
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of the list are two-tuples. The first element is the callable passed
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to L{deferFunction}. The second element is a copy of the scope stack
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at the time L{deferFunction} was called.
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@ivar _deferredAssignments: Similar to C{_deferredFunctions}, but for
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callables which are deferred assignment checks.
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"""
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nodeDepth = 0
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offset = None
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traceTree = False
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builtIns = set(builtin_vars).union(_MAGIC_GLOBALS)
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_customBuiltIns = os.environ.get('PYFLAKES_BUILTINS')
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if _customBuiltIns:
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builtIns.update(_customBuiltIns.split(','))
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del _customBuiltIns
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def __init__(self, tree, filename='(none)', builtins=None,
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withDoctest='PYFLAKES_DOCTEST' in os.environ):
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self._nodeHandlers = {}
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self._deferredFunctions = []
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self._deferredAssignments = []
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self.deadScopes = []
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self.messages = []
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self.filename = filename
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if builtins:
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self.builtIns = self.builtIns.union(builtins)
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self.withDoctest = withDoctest
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self.scopeStack = [ModuleScope()]
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self.exceptHandlers = [()]
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self.futuresAllowed = True
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self.root = tree
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self.handleChildren(tree)
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self.runDeferred(self._deferredFunctions)
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# Set _deferredFunctions to None so that deferFunction will fail
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# noisily if called after we've run through the deferred functions.
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self._deferredFunctions = None
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self.runDeferred(self._deferredAssignments)
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# Set _deferredAssignments to None so that deferAssignment will fail
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# noisily if called after we've run through the deferred assignments.
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self._deferredAssignments = None
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del self.scopeStack[1:]
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self.popScope()
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self.checkDeadScopes()
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def deferFunction(self, callable):
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"""
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Schedule a function handler to be called just before completion.
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This is used for handling function bodies, which must be deferred
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because code later in the file might modify the global scope. When
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`callable` is called, the scope at the time this is called will be
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restored, however it will contain any new bindings added to it.
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"""
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self._deferredFunctions.append((callable, self.scopeStack[:], self.offset))
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def deferAssignment(self, callable):
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"""
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Schedule an assignment handler to be called just after deferred
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function handlers.
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"""
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self._deferredAssignments.append((callable, self.scopeStack[:], self.offset))
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def runDeferred(self, deferred):
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"""
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Run the callables in C{deferred} using their associated scope stack.
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"""
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for handler, scope, offset in deferred:
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self.scopeStack = scope
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self.offset = offset
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handler()
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|
@property
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def scope(self):
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return self.scopeStack[-1]
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def popScope(self):
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self.deadScopes.append(self.scopeStack.pop())
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def checkDeadScopes(self):
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"""
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Look at scopes which have been fully examined and report names in them
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which were imported but unused.
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"""
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for scope in self.deadScopes:
|
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if isinstance(scope.get('__all__'), ExportBinding):
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all_names = set(scope['__all__'].names)
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if not scope.importStarred and \
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os.path.basename(self.filename) != '__init__.py':
|
|
# Look for possible mistakes in the export list
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undefined = all_names.difference(scope)
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for name in undefined:
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self.report(messages.UndefinedExport,
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scope['__all__'].source, name)
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else:
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all_names = []
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|
|
# Look for imported names that aren't used.
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for value in scope.values():
|
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if isinstance(value, Importation):
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used = value.used or value.name in all_names
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if not used:
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messg = messages.UnusedImport
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self.report(messg, value.source, value.name)
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for node in value.redefined:
|
|
if isinstance(self.getParent(node), ast.For):
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messg = messages.ImportShadowedByLoopVar
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elif used:
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continue
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else:
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messg = messages.RedefinedWhileUnused
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self.report(messg, node, value.name, value.source)
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|
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def pushScope(self, scopeClass=FunctionScope):
|
|
self.scopeStack.append(scopeClass())
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|
|
def report(self, messageClass, *args, **kwargs):
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self.messages.append(messageClass(self.filename, *args, **kwargs))
|
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|
|
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
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|
|
|
def getCommonAncestor(self, lnode, rnode, stop):
|
|
if stop in (lnode, rnode) or not (hasattr(lnode, 'parent') and
|
|
hasattr(rnode, 'parent')):
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return None
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|
if lnode is rnode:
|
|
return lnode
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|
|
|
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)
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|
|
|
def descendantOf(self, node, ancestors, stop):
|
|
for a in ancestors:
|
|
if self.getCommonAncestor(node, a, stop):
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return True
|
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return False
|
|
|
|
def differentForks(self, lnode, rnode):
|
|
"""True, if lnode and rnode are located on different forks of IF/TRY"""
|
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ancestor = self.getCommonAncestor(lnode, rnode, self.root)
|
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parts = getAlternatives(ancestor)
|
|
if parts:
|
|
for items in parts:
|
|
if self.descendantOf(lnode, items, ancestor) ^ \
|
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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 self.differentForks(node, existing.source):
|
|
|
|
parent_stmt = self.getParent(value.source)
|
|
if isinstance(existing, Importation) and isinstance(parent_stmt, ast.For):
|
|
self.report(messages.ImportShadowedByLoopVar,
|
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node, value.name, existing.source)
|
|
|
|
elif scope is self.scope:
|
|
if (isinstance(parent_stmt, ast.comprehension) and
|
|
not isinstance(self.getParent(existing.source),
|
|
(ast.For, ast.comprehension))):
|
|
self.report(messages.RedefinedInListComp,
|
|
node, value.name, existing.source)
|
|
elif not existing.used and value.redefines(existing):
|
|
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
|
|
# try local scope
|
|
try:
|
|
self.scope[name].used = (self.scope, node)
|
|
except KeyError:
|
|
pass
|
|
else:
|
|
return
|
|
|
|
scopes = [scope for scope in self.scopeStack[:-1]
|
|
if isinstance(scope, (FunctionScope, ModuleScope, GeneratorScope))]
|
|
if isinstance(self.scope, GeneratorScope) and scopes[-1] != self.scopeStack[-2]:
|
|
scopes.append(self.scopeStack[-2])
|
|
|
|
# try enclosing function scopes and global scope
|
|
importStarred = self.scope.importStarred
|
|
for scope in reversed(scopes):
|
|
importStarred = importStarred or scope.importStarred
|
|
try:
|
|
scope[name].used = (self.scope, node)
|
|
except KeyError:
|
|
pass
|
|
else:
|
|
return
|
|
|
|
# look in the built-ins
|
|
if importStarred or name in self.builtIns:
|
|
return
|
|
if name == '__path__' and os.path.basename(self.filename) == '__init__.py':
|
|
# the special name __path__ is valid only in packages
|
|
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, (ast.For, 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)
|
|
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 can not 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 handleChildren(self, tree, omit=None):
|
|
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)
|
|
# 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:
|
|
(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
|
|
node_offset = self.offset or (0, 0)
|
|
self.pushScope()
|
|
underscore_in_builtins = '_' in self.builtIns
|
|
if not underscore_in_builtins:
|
|
self.builtIns.add('_')
|
|
for example in examples:
|
|
try:
|
|
tree = compile(example.source, "<doctest>", "exec", ast.PyCF_ONLY_AST)
|
|
except SyntaxError:
|
|
e = sys.exc_info()[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
|
|
if not underscore_in_builtins:
|
|
self.builtIns.remove('_')
|
|
self.popScope()
|
|
|
|
def ignore(self, node):
|
|
pass
|
|
|
|
# "stmt" type nodes
|
|
DELETE = PRINT = FOR = ASYNCFOR = WHILE = IF = WITH = WITHITEM = \
|
|
ASYNCWITH = ASYNCWITHITEM = RAISE = TRYFINALLY = ASSERT = EXEC = \
|
|
EXPR = ASSIGN = handleChildren
|
|
|
|
CONTINUE = BREAK = PASS = ignore
|
|
|
|
# "expr" type nodes
|
|
BOOLOP = BINOP = UNARYOP = IFEXP = DICT = SET = \
|
|
COMPARE = CALL = REPR = ATTRIBUTE = SUBSCRIPT = LIST = TUPLE = \
|
|
STARRED = NAMECONSTANT = handleChildren
|
|
|
|
NUM = STR = BYTES = ELLIPSIS = 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 = ignore
|
|
|
|
# additional node types
|
|
COMPREHENSION = KEYWORD = handleChildren
|
|
|
|
def GLOBAL(self, node):
|
|
"""
|
|
Keep track of globals declarations.
|
|
"""
|
|
# In doctests, the global scope is an anonymous function at index 1.
|
|
global_scope_index = 1 if self.withDoctest 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.
|
|
self.messages = [
|
|
m for m in self.messages if not
|
|
isinstance(m, messages.UndefinedName) and not
|
|
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)):
|
|
self.handleNodeStore(node)
|
|
elif isinstance(node.ctx, ast.Del):
|
|
self.handleNodeDelete(node)
|
|
else:
|
|
# must be a Param context -- this only happens for names in function
|
|
# arguments, but these aren't dispatched through here
|
|
raise RuntimeError("Got impossible expression context: %r" % (node.ctx,))
|
|
|
|
def RETURN(self, node):
|
|
if isinstance(self.scope, ClassScope):
|
|
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):
|
|
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))
|
|
if self.withDoctest:
|
|
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 PY33 else wildcard.arg)
|
|
if is_py3_func:
|
|
if PY33: # Python 2.5 to 3.3
|
|
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 child in annotations + defaults:
|
|
if child:
|
|
self.handleNode(child, node)
|
|
|
|
def runFunction():
|
|
|
|
self.pushScope()
|
|
for name in args:
|
|
self.addBinding(node, Argument(name, node))
|
|
if isinstance(node.body, list):
|
|
# case for FunctionDefs
|
|
for stmt in node.body:
|
|
self.handleNode(stmt, node)
|
|
else:
|
|
# case for Lambdas
|
|
self.handleNode(node.body, node)
|
|
|
|
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 PY32:
|
|
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 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)
|
|
if self.withDoctest:
|
|
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 IMPORT(self, node):
|
|
for alias in node.names:
|
|
name = alias.asname or alias.name
|
|
importation = Importation(name, node)
|
|
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
|
|
|
|
for alias in node.names:
|
|
if alias.name == '*':
|
|
self.scope.importStarred = True
|
|
self.report(messages.ImportStarUsed, node, node.module)
|
|
continue
|
|
name = alias.asname or alias.name
|
|
importation = Importation(name, node)
|
|
if node.module == '__future__':
|
|
importation.used = (self.scope, node)
|
|
self.addBinding(node, importation)
|
|
|
|
def TRY(self, node):
|
|
handler_names = []
|
|
# List the exception handlers
|
|
for handler in 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))
|
|
# 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):
|
|
# 3.x: in addition to handling children, we must handle the name of
|
|
# the exception, which is not a Name node, but a simple string.
|
|
if isinstance(node.name, str):
|
|
self.handleNodeStore(node)
|
|
self.handleChildren(node)
|