Add ruff rules PERF for performance #4492
Merged
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Overview: What does this pull request change?
Add ruff rules PERF for performance
Motivation and Explanation: Why and how do your changes improve the library?
Users will be happier if our code runs faster.
Links to added or changed documentation pages
https://docs.astral.sh/ruff/rules/#perflint-perf
Further Information and Comments
%
ruff check --statisticsAlso upgrade pre-commit hooks and move
mypyto be the last hook because it is so damn slow.%
ruff rule PERF401manual-list-comprehension (PERF401)
Derived from the Perflint linter.
Fix is sometimes available.
What it does
Checks for
forloops that can be replaced by a list comprehension.Why is this bad?
When creating a transformed list from an existing list using a for-loop,
prefer a list comprehension. List comprehensions are more readable and
more performant.
Using the below as an example, the list comprehension is ~10% faster on
Python 3.11, and ~25% faster on Python 3.10.
Note that, as with all
perflintrules, this is only intended as amicro-optimization, and will have a negligible impact on performance in
most cases.
Example
Use instead:
If you're appending to an existing list, use the
extendmethod instead:Reviewer Checklist