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gh-157840: Special-case member descriptors when using hasattr - #157866
ZeroIntensity merged 5 commits into
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serhiy-storchaka
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Does it affect three-argument getattr()?
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| // gh-157840: When using hasattr(), slot members without assigned values | ||
| // need to go through __get__(), which involves creating an AttributeError | ||
| // object (which is really slow). There's no way to supply "suppress" | ||
| // to the tp_descr_get() function, so we just special-case member | ||
| // descriptors here to improve performance. |
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Could you please simplify the comment, leaving the substantial part?
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Done
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Yeah -- performance there is also improved by this PR. |
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serhiy-storchaka
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LGTM. 👍
Two nits.
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| if (suppress && Py_IS_TYPE(descr, &PyMemberDescr_Type)) { | ||
| PyMemberDef *member = ((PyMemberDescrObject *)descr)->d_member; | ||
| if (member->type == Py_T_OBJECT_EX | ||
| && !(member->flags & Py_AUDIT_READ) && |
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Inconsistent formatting. && after and before line split.
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| @@ -0,0 +1,2 @@ | |||
| Speed up calls to :func:`hasattr` for unassigned attributes in an object's | |||
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Mention also getattr.
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Thanks for the review! |
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Before this PR:
$ ./python -m timeit -s 'class Test: __slots__ = ("x",)' -s 't = Test()' 'hasattr(t,"x")' --number 100000000 100000000 loops, best of 5: 192 nsec per loopAfter:
$ ./python -m timeit -s 'class Test: __slots__ = ("x",)' -s 't = Test()' 'hasattr(t,"x")' --number 100000000 100000000 loops, best of 5: 30.8 nsec per loop