def visit_If(self, node):
self.check_type(node.test, Bool())
test_value = static_evaluate(node.test, self.context())
if not isinstance(test_value, UnknownValue):
self.warn('constant-if-condition', node)
ext_ctx = self.context()
if_inferences, else_inferences = maybe_inferences(node.test, ext_ctx)
# don't visit unreachable code
if test_value is True:
self._visit_branch(node.body, if_inferences)
return
if test_value is False:
self._visit_branch(node.orelse, else_inferences)
return
if_scope = self._visit_branch(node.body, if_inferences)
else_scope = self._visit_branch(node.orelse, else_inferences)
diffs = set(if_scope.names()) ^ set(else_scope.names())
for diff in diffs:
if diff not in self._context:
self.warn('conditionally-assigned', node, diff)
common = set(if_scope.names()) & set(else_scope.names())
for name in common:
types = [if_scope.get_type(name), else_scope.get_type(name)]
unified_type = unify_types(types)
self._context.add(Symbol(name, unified_type))
if isinstance(unified_type, Unknown):
if not any(isinstance(x, Unknown) for x in types):
self.warn('conditional-type', node, name)
def visit_If(self, node):
self.check_type(node.test, Bool())
test_value = static_evaluate(node.test, self.context())
if not isinstance(test_value, UnknownValue):
self.warn('constant-if-condition', node)
ext_ctx = self.context()
if_inferences, else_inferences = maybe_inferences(node.test, ext_ctx)
# don't visit unreachable code
if test_value is True:
self._visit_branch(node.body, if_inferences)
return
if test_value is False:
self._visit_branch(node.orelse, else_inferences)
return
if_scope = self._visit_branch(node.body, if_inferences)
else_scope = self._visit_branch(node.orelse, else_inferences)
diffs = set(if_scope.names()) ^ set(else_scope.names())
for diff in diffs:
if diff not in self._context:
self.warn('conditionally-assigned', node, diff)
common = set(if_scope.names()) & set(else_scope.names())
for name in common:
types = [if_scope.get_type(name), else_scope.get_type(name)]
unified_type = unify_types(types)
self._context.add(Symbol(name, unified_type))
if isinstance(unified_type, Unknown):
if not any(isinstance(x, Unknown) for x in types):
self.warn('conditional-type', node, name)
def _check_return(self, return_type, static_value=None):
previous_type = self._context.get_type()
new_type = (unify_types([previous_type, return_type])
if previous_type is not None else return_type)
value = (static_value or UnknownValue()
if previous_type is None else UnknownValue())
self._context.set_return(Symbol('return', new_type, value))
def _check_return(self, return_type, static_value=None):
previous_type = self._context.get_type()
new_type = (unify_types([previous_type, return_type])
if previous_type is not None else return_type)
value = (static_value or UnknownValue() if previous_type is None else
UnknownValue())
self._context.set_return(Symbol('return', new_type, value))