def _handle_conditional_node(self, node, name): if utils.condition_is_always_false(node.test): self._define( self.unreachable_code, name, node, last_node=node.body[-1], message="unsatisfiable '{name}' condition".format(**locals()), confidence=100, ) elif utils.condition_is_always_true(node.test): else_body = node.orelse if else_body: self._define( self.unreachable_code, "else", else_body[0], last_node=else_body[-1], message="unreachable 'else' block", confidence=100, ) elif name == "if": # Redundant if-condition without else block. self._define( self.unreachable_code, name, node, message="redundant if-condition".format(**locals()), confidence=100, )
def visit_If(self, node): else_body = getattr(node, 'orelse') if utils.condition_is_always_true(node.test) and else_body: self._define( self.unreachable_code, 'else', else_body[0], last_node=else_body[-1], message="unreachable 'else' block", confidence=100) elif utils.condition_is_always_false(node.test): self._define( self.unreachable_code, 'if', node, last_node=node.body[-1], message="unsatisfiable 'if' condition", confidence=100)
def _handle_conditional_node(self, node, name): if utils.condition_is_always_false(node.test): self._define( self.unreachable_code, name, node, last_node=node.body[-1], message="unsatisfiable '{name}' condition".format(**locals()), confidence=100) else: else_body = getattr(node, 'orelse') if utils.condition_is_always_true(node.test) and else_body: self._define( self.unreachable_code, 'else', else_body[0], last_node=else_body[-1], message="unreachable 'else' block", confidence=100)
def test_errors(): conditions = [ 'foo', '__name__ == "__main__"', 'chr(-1)', 'getattr(True, "foo")', 'hasattr(str, "foo")', 'isinstance(True, True)', 'globals()', 'locals()', '().__class__', ] for condition in conditions: condition = ast.parse(condition, mode='eval').body assert not utils.condition_is_always_false(condition) assert not utils.condition_is_always_true(condition)
def visit_If(self, node): else_body = getattr(node, 'orelse') if utils.condition_is_always_true(node.test) and else_body: self._define(self.unreachable_code, 'else', else_body[0], last_node=else_body[-1], message="unreachable 'else' block", confidence=100) elif utils.condition_is_always_false(node.test): self._define(self.unreachable_code, 'if', node, last_node=node.body[-1], message="unsatisfiable 'if' condition", confidence=100)
def test_errors(): conditions = [ "foo", '__name__ == "__main__"', "chr(-1)", 'getattr(True, "foo")', 'hasattr(str, "foo")', "isinstance(True, True)", "globals()", "locals()", "().__class__", ] for condition in conditions: condition = ast.parse(condition, mode="eval").body assert not utils.condition_is_always_false(condition) assert not utils.condition_is_always_true(condition)
def test_complex_conditions(): conditions = [ ('foo and False', True, False), ('foo or False', False, False), ('foo and True', False, False), ('foo or True', False, True), ('False and foo', True, False), ('False and 1', True, False), ('not False', False, True), ('not True', True, False), ('not foo', False, False), ('foo and (False or [])', True, False), ('(foo and bar) or {"a": 1}', False, True), ] for condition, always_false, always_true in conditions: condition = ast.parse(condition, mode='eval').body assert not (always_false and always_true) assert utils.condition_is_always_false(condition) == always_false assert utils.condition_is_always_true(condition) == always_true
def test_complex_conditions(): conditions = [ ("foo and False", True, False), ("foo or False", False, False), ("foo and True", False, False), ("foo or True", False, True), ("False and foo", True, False), ("False and 1", True, False), ("not False", False, True), ("not True", True, False), ("not foo", False, False), ("foo and (False or [])", True, False), ('(foo and bar) or {"a": 1}', False, True), ] for condition, always_false, always_true in conditions: condition = ast.parse(condition, mode="eval").body assert not (always_false and always_true) assert utils.condition_is_always_false(condition) == always_false assert utils.condition_is_always_true(condition) == always_true
def _handle_conditional_node(self, node, name): if utils.condition_is_always_false(node.test): self._define( self.unreachable_code, name, node, last_node=node.body if isinstance(node, ast.IfExp) else node.body[-1], message=f"unsatisfiable '{name}' condition", confidence=100, ) elif utils.condition_is_always_true(node.test): else_body = node.orelse if name == "ternary": self._define( self.unreachable_code, name, else_body, message="unreachable 'else' expression", confidence=100, ) elif else_body: self._define( self.unreachable_code, "else", else_body[0], last_node=else_body[-1], message="unreachable 'else' block", confidence=100, ) elif name == "if": # Redundant if-condition without else block. self._define( self.unreachable_code, name, node, message="redundant if-condition", confidence=100, )
def check_condition(code, result): condition = ast.parse(code, mode='eval').body if result: assert utils.condition_is_always_true(condition) else: assert utils.condition_is_always_false(condition)