diff options
Diffstat (limited to 'pyflakes/checker.py')
| -rw-r--r-- | pyflakes/checker.py | 62 |
1 files changed, 49 insertions, 13 deletions
diff --git a/pyflakes/checker.py b/pyflakes/checker.py index 1fbad48..16c783f 100644 --- a/pyflakes/checker.py +++ b/pyflakes/checker.py @@ -79,6 +79,10 @@ else: LOOP_TYPES = (ast.While, ast.For) FUNCTION_TYPES = (ast.FunctionDef,) +if PY36_PLUS: + ANNASSIGN_TYPES = (ast.AnnAssign,) +else: + ANNASSIGN_TYPES = () if PY38_PLUS: def _is_singleton(node): # type: (ast.AST) -> bool @@ -528,6 +532,16 @@ class Assignment(Binding): """ +class Annotation(Binding): + """ + Represents binding a name to a type without an associated value. + + As long as this name is not assigned a value in another binding, it is considered + undefined for most purposes. One notable exception is using the name as a type + annotation. + """ + + class FunctionDefinition(Definition): pass @@ -732,6 +746,12 @@ def is_typing_overload(value, scope_stack): ) +class AnnotationState: + NONE = 0 + STRING = 1 + BARE = 2 + + def in_annotation(func): @functools.wraps(func) def in_annotation_func(self, *args, **kwargs): @@ -740,6 +760,14 @@ def in_annotation(func): return in_annotation_func +def in_string_annotation(func): + @functools.wraps(func) + def in_annotation_func(self, *args, **kwargs): + with self._enter_annotation(AnnotationState.STRING): + return func(self, *args, **kwargs) + return in_annotation_func + + def make_tokens(code): # PY3: tokenize.tokenize requires readline of bytes if not isinstance(code, bytes): @@ -826,7 +854,7 @@ class Checker(object): nodeDepth = 0 offset = None traceTree = False - _in_annotation = False + _in_annotation = AnnotationState.NONE _in_typing_literal = False _in_deferred = False @@ -1146,8 +1174,11 @@ class Checker(object): # iteration continue - if (name == 'print' and - isinstance(scope.get(name, None), Builtin)): + binding = scope.get(name, None) + if isinstance(binding, Annotation) and not self._in_postponed_annotation: + continue + + if name == 'print' and isinstance(binding, Builtin): parent = self.getParent(node) if (isinstance(parent, ast.BinOp) and isinstance(parent.op, ast.RShift)): @@ -1222,7 +1253,9 @@ class Checker(object): break parent_stmt = self.getParent(node) - if isinstance(parent_stmt, (FOR_TYPES, ast.comprehension)) or ( + if isinstance(parent_stmt, ANNASSIGN_TYPES) and parent_stmt.value is None: + binding = Annotation(name, node) + elif isinstance(parent_stmt, (FOR_TYPES, ast.comprehension)) or ( parent_stmt != node._pyflakes_parent and not self.isLiteralTupleUnpacking(parent_stmt)): binding = Binding(name, node) @@ -1265,13 +1298,20 @@ class Checker(object): self.report(messages.UndefinedName, node, name) @contextlib.contextmanager - def _enter_annotation(self): - orig, self._in_annotation = self._in_annotation, True + def _enter_annotation(self, ann_type=AnnotationState.BARE): + orig, self._in_annotation = self._in_annotation, ann_type try: yield finally: self._in_annotation = orig + @property + def _in_postponed_annotation(self): + return ( + self._in_annotation == AnnotationState.STRING or + self.annotationsFutureEnabled + ) + def _handle_type_comments(self, node): for (lineno, col_offset), comment in self._type_comments.get(node, ()): comment = comment.split(':', 1)[1].strip() @@ -1399,7 +1439,7 @@ class Checker(object): self.popScope() self.scopeStack = saved_stack - @in_annotation + @in_string_annotation def handleStringAnnotation(self, s, node, ref_lineno, ref_col_offset, err): try: tree = ast.parse(s) @@ -1611,7 +1651,7 @@ class Checker(object): len(node.args) >= 1 and isinstance(node.args[0], ast.Str) ): - with self._enter_annotation(): + with self._enter_annotation(AnnotationState.STRING): self.handleNode(node.args[0], node) self.handleChildren(node) @@ -2224,11 +2264,7 @@ class Checker(object): 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.handleNode(node.target, node) self.handleAnnotation(node.annotation, node) if node.value: # If the assignment has value, handle the *value* now. |