diff --git a/src/test_typing_extensions.py b/src/test_typing_extensions.py index 79c0274d..208382a0 100644 --- a/src/test_typing_extensions.py +++ b/src/test_typing_extensions.py @@ -31,6 +31,7 @@ from typing_extensions import NamedTuple from typing_extensions import override, deprecated from _typed_dict_test_helper import Foo, FooGeneric +import warnings # Flags used to mark tests that only apply after a specific # version of the typing module. @@ -203,7 +204,7 @@ def static_method_bad_order(): class DeprecatedTests(BaseTestCase): - def test_deprecated(self): + def test_dunder_deprecated(self): @deprecated("A will go away soon") class A: pass @@ -230,6 +231,123 @@ def h(x): self.assertEqual(len(overloads), 2) self.assertEqual(overloads[0].__deprecated__, "no more ints") + def test_class(self): + @deprecated("A will go away soon") + class A: + pass + + with self.assertWarnsRegex(DeprecationWarning, "A will go away soon"): + A() + with self.assertRaises(TypeError): + A(42) + + @deprecated("HasInit will go away soon") + class HasInit: + def __init__(self, x): + self.x = x + + with self.assertWarnsRegex(DeprecationWarning, "HasInit will go away soon"): + instance = HasInit(42) + self.assertEqual(instance.x, 42) + + has_new_called = False + + @deprecated("HasNew will go away soon") + class HasNew: + def __new__(cls, x): + nonlocal has_new_called + has_new_called = True + return super().__new__(cls) + + def __init__(self, x) -> None: + self.x = x + + with self.assertWarnsRegex(DeprecationWarning, "HasNew will go away soon"): + instance = HasNew(42) + self.assertEqual(instance.x, 42) + self.assertTrue(has_new_called) + new_base_called = False + + class NewBase: + def __new__(cls, x): + nonlocal new_base_called + new_base_called = True + return super().__new__(cls) + + def __init__(self, x) -> None: + self.x = x + + @deprecated("HasInheritedNew will go away soon") + class HasInheritedNew(NewBase): + pass + + with self.assertWarnsRegex(DeprecationWarning, "HasInheritedNew will go away soon"): + instance = HasInheritedNew(42) + self.assertEqual(instance.x, 42) + self.assertTrue(new_base_called) + + def test_function(self): + @deprecated("b will go away soon") + def b(): + pass + + with self.assertWarnsRegex(DeprecationWarning, "b will go away soon"): + b() + + def test_method(self): + class Capybara: + @deprecated("x will go away soon") + def x(self): + pass + + instance = Capybara() + with self.assertWarnsRegex(DeprecationWarning, "x will go away soon"): + instance.x() + + def test_property(self): + class Capybara: + @property + @deprecated("x will go away soon") + def x(self): + pass + + @property + def no_more_setting(self): + return 42 + + @no_more_setting.setter + @deprecated("no more setting") + def no_more_setting(self, value): + pass + + instance = Capybara() + with self.assertWarnsRegex(DeprecationWarning, "x will go away soon"): + instance.x + + with warnings.catch_warnings(): + warnings.simplefilter("error") + self.assertEqual(instance.no_more_setting, 42) + + with self.assertWarnsRegex(DeprecationWarning, "no more setting"): + instance.no_more_setting = 42 + + def test_category(self): + @deprecated("c will go away soon", category=RuntimeWarning) + def c(): + pass + + with self.assertWarnsRegex(RuntimeWarning, "c will go away soon"): + c() + + def test_turn_off_warnings(self): + @deprecated("d will go away soon", category=None) + def d(): + pass + + with warnings.catch_warnings(): + warnings.simplefilter("error") + d() + class AnyTests(BaseTestCase): def test_can_subclass(self): diff --git a/src/typing_extensions.py b/src/typing_extensions.py index c32c63d1..6ae0c34c 100644 --- a/src/typing_extensions.py +++ b/src/typing_extensions.py @@ -7,6 +7,7 @@ import sys import types as _types import typing +import warnings __all__ = [ @@ -2135,7 +2136,12 @@ def method(self) -> None: else: _T = typing.TypeVar("_T") - def deprecated(__msg: str) -> typing.Callable[[_T], _T]: + def deprecated( + __msg: str, + *, + category: typing.Optional[typing.Type[Warning]] = DeprecationWarning, + stacklevel: int = 1, + ) -> typing.Callable[[_T], _T]: """Indicate that a class, function or overload is deprecated. Usage: @@ -2167,8 +2173,40 @@ def g(x: str) -> int: ... """ def decorator(__arg: _T) -> _T: - __arg.__deprecated__ = __msg - return __arg + if category is None: + __arg.__deprecated__ = __msg + return __arg + elif isinstance(__arg, type): + original_new = __arg.__new__ + has_init = __arg.__init__ is not object.__init__ + + @functools.wraps(original_new) + def __new__(cls, *args, **kwargs): + warnings.warn(__msg, category=category, stacklevel=stacklevel + 1) + # Mirrors a similar check in object.__new__. + if not has_init and (args or kwargs): + raise TypeError(f"{cls.__name__}() takes no arguments") + if original_new is not object.__new__: + return original_new(cls, *args, **kwargs) + else: + return original_new(cls) + + __arg.__new__ = staticmethod(__new__) + __arg.__deprecated__ = __new__.__deprecated__ = __msg + return __arg + elif callable(__arg): + @functools.wraps(__arg) + def wrapper(*args, **kwargs): + warnings.warn(__msg, category=category, stacklevel=stacklevel + 1) + return __arg(*args, **kwargs) + + __arg.__deprecated__ = wrapper.__deprecated__ = __msg + return wrapper + else: + raise TypeError( + "@deprecated decorator with non-None category must be applied to " + f"a class or callable, not {__arg!r}" + ) return decorator