diff options
| -rw-r--r-- | Lib/test/test_typing.py | 10 | ||||
| -rw-r--r-- | Lib/typing.py | 5 | ||||
| -rw-r--r-- | Misc/NEWS.d/next/Core and Builtins/2021-09-07-17-10-16.bpo-45121.iG-Hsf.rst | 2 |
3 files changed, 17 insertions, 0 deletions
diff --git a/Lib/test/test_typing.py b/Lib/test/test_typing.py index 459af25..c84ff0f 100644 --- a/Lib/test/test_typing.py +++ b/Lib/test/test_typing.py @@ -1604,6 +1604,16 @@ class ProtocolTests(BaseTestCase): with self.assertRaisesRegex(TypeError, "@runtime_checkable"): isinstance(1, P) + def test_super_call_init(self): + class P(Protocol): + x: int + + class Foo(P): + def __init__(self): + super().__init__() + + Foo() # Previously triggered RecursionError + class GenericTests(BaseTestCase): diff --git a/Lib/typing.py b/Lib/typing.py index 24f834e..5873d53 100644 --- a/Lib/typing.py +++ b/Lib/typing.py @@ -1404,6 +1404,11 @@ def _no_init_or_replace_init(self, *args, **kwargs): if cls._is_protocol: raise TypeError('Protocols cannot be instantiated') + # Already using a custom `__init__`. No need to calculate correct + # `__init__` to call. This can lead to RecursionError. See bpo-45121. + if cls.__init__ is not _no_init_or_replace_init: + return + # Initially, `__init__` of a protocol subclass is set to `_no_init_or_replace_init`. # The first instantiation of the subclass will call `_no_init_or_replace_init` which # searches for a proper new `__init__` in the MRO. The new `__init__` diff --git a/Misc/NEWS.d/next/Core and Builtins/2021-09-07-17-10-16.bpo-45121.iG-Hsf.rst b/Misc/NEWS.d/next/Core and Builtins/2021-09-07-17-10-16.bpo-45121.iG-Hsf.rst new file mode 100644 index 0000000..19eb331 --- /dev/null +++ b/Misc/NEWS.d/next/Core and Builtins/2021-09-07-17-10-16.bpo-45121.iG-Hsf.rst @@ -0,0 +1,2 @@ +Fix issue where ``Protocol.__init__`` raises ``RecursionError`` when it's +called directly or via ``super()``. Patch provided by Yurii Karabas. |