TYP: type insert and nsmallest/largest #43865
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pandas/core/algorithms.py
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| super().__init__(obj, n, keep) | ||
| if not is_list_like(columns) or isinstance(columns, tuple): | ||
| columns = [columns] | ||
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| assert isinstance(columns, abc.Iterable) |
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if adding an assert for mypy, append an inline comment # for mypy since we can't catch these when no longer necessary (i.e. if TypeGuard can narrow the types from the is_list_like condition.)
Alternatively, use a cast. we use cast elsewhere after is_* calls and we can detect when not needed with warn_redundant_casts mypy setting.
maybe Iterable from typing instead of collections but typing.Iterable is deprecated https://docs.python.org/3/library/typing.html#typing.Iterable
so okay to use typing.Iterable for consistency and also okay to keep the import from collections.
we will need to do a sweep at some point to migrate the deprecated uses.
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Thx this helps a lot. I have replaced the assert with a cast. Is cast preferred in general?
Should we prefer the abc imports in general if the typing equivalent is deprecated?
cc @simonjayhawkins Could you have a look and give some feedback if this is ok so?