[perflint] Handle tuples in dictionary comprehensions (PERF403)#19934
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Thank you! I'll try to get to it this week :) |
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Thank you, this looks great! I just had a few small suggestions.
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@ntBre Thanks again! |
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perflint] Handle tuples in dictionary comprehensions (PERF403)
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…stral-sh#19934) This pull request fixes the bug described in issue [astral-sh#19153](astral-sh#19153). The issue occurred when `PERF403` incorrectly flagged cases involving tuple unpacking in a for loop. For example: ```python def f(): v = {} for (o, p), x in [("op", "x")]: v[x] = o, p ``` This code was wrongly suggested to be rewritten into a dictionary comprehension, which changes the semantics. Changes in this PR: Updated the `PERF403` rule to correctly handle tuple unpacking in loop targets. Added regression tests to ensure this case (and similar ones) are no longer flagged incorrectly. Why: This ensures that `PERF403` only triggers when a dictionary comprehension is semantically equivalent to the original loop, preventing false positives. --------- Co-authored-by: Brent Westbrook <brentrwestbrook@gmail.com>
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This pull request fixes the bug described in issue #19153.
The issue occurred when
PERF403incorrectly flagged cases involving tuple unpacking in a for loop. For example:This code was wrongly suggested to be rewritten into a dictionary comprehension, which changes the semantics.
Changes in this PR:
Updated the
PERF403rule to correctly handle tuple unpacking in loop targets.Added regression tests to ensure this case (and similar ones) are no longer flagged incorrectly.
Why:
This ensures that
PERF403only triggers when a dictionary comprehension is semantically equivalent to the original loop, preventing false positives.