bpo-29581: bpo-29581: Make ABCMeta.new pass **kwargs to type.__ne… · python/cpython@6fb12b5 (original) (raw)
Navigation Menu
- GitHub Copilot Write better code with AI
- GitHub Models New Manage and compare prompts
- GitHub Advanced Security Find and fix vulnerabilities
- Actions Automate any workflow
- Codespaces Instant dev environments
- Issues Plan and track work
- Code Review Manage code changes
- Discussions Collaborate outside of code
- Code Search Find more, search less
- Explore
- Pricing
Provide feedback
Saved searches
Use saved searches to filter your results more quickly
Appearance settings
Commit 6fb12b5
authored and
committed
Many metaclasses in the standard library don't play nice with __init_subclass__. This bug makes ABCMeta in particular with __init_subclass__, which is an 80/20 solution for me personally. AFAICT, a general solution to this problem requires updating all metaclasses in the standard library to make sure they pass **kwargs to type.__new__, whereas this PR only fixes ABCMeta. For context, seehttps://bugs.python.org/issue29581. * added a test combining ABCMeta and __init_subclass__ * Added NEWS item (cherry picked from commit bd583ef) * [3.6] bpo-29581: Make ABCMeta.__new__ pass **kwargs to type.__new__ (GH-527) Many metaclasses in the standard library don't play nice with __init_subclass__. This bug makes ABCMeta in particular with __init_subclass__, which is an 80/20 solution for me personally. AFAICT, a general solution to this problem requires updating all metaclasses in the standard library to make sure they pass **kwargs to type.__new__, whereas this PR only fixes ABCMeta. For context, seehttps://bugs.python.org/issue29581. * added a test combining ABCMeta and __init_subclass__ * Added NEWS item. (cherry picked from commit bd583ef) * **kwargs -> ``kwargs`` in attempts to fix the Travis build. * Quote the **kwargs
File tree
3 files changed
lines changed
3 files changed
lines changed
Lines changed: 2 additions & 2 deletions
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -129,8 +129,8 @@ class ABCMeta(type): | ||
| 129 | 129 | # external code. |
| 130 | 130 | _abc_invalidation_counter = 0 |
| 131 | 131 | |
| 132 | -def __new__(mcls, name, bases, namespace): | |
| 133 | -cls = super().__new__(mcls, name, bases, namespace) | |
| 132 | +def __new__(mcls, name, bases, namespace, **kwargs): | |
| 133 | +cls = super().__new__(mcls, name, bases, namespace, **kwargs) | |
| 134 | 134 | # Compute set of abstract method names |
| 135 | 135 | abstracts = {name |
| 136 | 136 | for name, value in namespace.items() |
Lines changed: 12 additions & 0 deletions
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -404,5 +404,17 @@ class C(A, B): | ||
| 404 | 404 | self.assertEqual(B.counter, 1) |
| 405 | 405 | |
| 406 | 406 | |
| 407 | +class TestABCWithInitSubclass(unittest.TestCase): | |
| 408 | +def test_works_with_init_subclass(self): | |
| 409 | +saved_kwargs = {} | |
| 410 | +class ReceivesClassKwargs: | |
| 411 | +def __init_subclass__(cls, **kwargs): | |
| 412 | +super().__init_subclass__() | |
| 413 | +saved_kwargs.update(kwargs) | |
| 414 | +class Receiver(ReceivesClassKwargs, abc.ABC, x=1, y=2, z=3): | |
| 415 | +pass | |
| 416 | +self.assertEqual(saved_kwargs, dict(x=1, y=2, z=3)) | |
| 417 | + | |
| 418 | + | |
| 407 | 419 | if __name__ == "__main__": |
| 408 | 420 | unittest.main() |
Lines changed: 3 additions & 0 deletions
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -45,6 +45,9 @@ Core and Builtins | ||
| 45 | 45 | Library |
| 46 | 46 | ------- |
| 47 | 47 | |
| 48 | +- bpo-29581: ABCMeta.__new__ now accepts ``**kwargs``, allowing abstract base | |
| 49 | + classes to use keyword parameters in __init_subclass__. Patch by Nate Soares. | |
| 50 | + | |
| 48 | 51 | - bpo-30557: faulthandler now correctly filters and displays exception codes |
| 49 | 52 | on Windows |
| 50 | 53 |