Special case None.__bool__() #5780
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test-data/unit/check-basic.test
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| none = None | ||
| b = none.__bool__() | ||
| s = 'hi' | ||
| s = b # E: Incompatible types in assignment (expression has type "bool", variable has type "str") |
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You can just use reveal_type() to check that the type is correct.
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You can just use
reveal_type()to check that the type is correct.
Done, thanks!
mypy/checkmember.py
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| is_super, is_operator, builtin_type, not_ready_callback, msg, | ||
| original_type=original_type, chk=chk) | ||
| if name == '__bool__': | ||
| # The only attribute of NoneType that is not inherited from object. |
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The position and content of this comment should be updated.
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The position and content of this comment should be updated.
I've updated the position and content. Hopefully for the better. 😅
mypy/checkmember.py
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| return analyze_member_access(name, builtin_type('builtins.object'), node, is_lvalue, | ||
| is_super, is_operator, builtin_type, not_ready_callback, msg, | ||
| original_type=original_type, chk=chk) | ||
| if name == '__bool__': |
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Note that that this special case should be added only on Python 3.
Please also add a test that None.__bool__ fails on Python 2.
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Note that that this special case should be added only on Python 3.
Oops, I'd missed that. Thanks, fixed.
Please also add a test that
None.__bool__fails on Python 2.
Done.
mypy/checkmember.py
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| is_python_2 = chk.options.python_version[0] == 2 | ||
| # In Python 2 "None" has exactly the same attributes as "object". Python 3 adds a single | ||
| # extra attribute, "__bool__". | ||
| if not is_python_2 and name == '__bool__': |
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It would read more natural if you use if is_python_3 ... here and define it as is_python_3 = chk.options.python_version[0] >= 3 above.
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It would read more natural if you use
if is_python_3 ...here and define it asis_python_3 = chk.options.python_version[0] >= 3above.
Done. Though now is_python_3 will be True on Python 4. 😸
Thanks!
2 participants
Resolves #5680.
Sorry, I don't know if I'm doing this right. We started using Mypy about half a year ago, so I thought I'd try to make some small contribution. The comment from @ilevkivskyi made this sound simple enough, and the test passes, but I'm not entirely confident of this. There are no other hacks like this in
checkmember.py...Also I have no idea where this test belongs. Seems like a "basic" thing, so I put it in
check-basic.test. 😅Thanks!