Use a set for TargetPython.get_tags for performance #12204

This speeds up a representative pip-compile by about 40% ``` λ hyperfine -w 1 -M 3 -p 'rm req.txt || true' 'python -m piptools compile req.in --output-file req.txt --strip-extras --resolver=backtracking' Benchmark 1: python -m piptools compile req.in --output-file req.txt --strip-extras --resolver=backtracking Time (mean ± σ): 28.552 s ± 2.552 s [User: 20.477 s, System: 1.547 s] Range (min … max): 26.446 s … 31.390 s 3 runs λ hyperfine -w 1 -M 3 -p 'rm req.txt || true' 'python -m piptools compile req.in --output-file req.txt --strip-extras --resolver=backtracking' Benchmark 1: python -m piptools compile req.in --output-file req.txt --strip-extras --resolver=backtracking Time (mean ± σ): 17.570 s ± 0.450 s [User: 11.537 s, System: 1.345 s] Range (min … max): 17.095 s … 17.989 s 3 runs ``` This makes the set.isdisjoint operation done over here much cheaper: https://github.com/pypa/pip/blob/593b85f4a/src/pip/_internal/models/wheel.py#L92 The reason for this is because a Python usually has a lot of supported tags. The Python I used above has 2000 supported tags! Whereas a wheel usually only has one or two file tags. The CPython code will unfortunately iterate over all 2000 tags to check if there's a match. Only if the other collection is a set will CPython think to swap the operands to iterate over the shorter collection: https://github.com/python/cpython/blob/35963da40f/Objects/setobject.c#L1352

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Use a set for TargetPython.get_tags for performance #12204

Use a set for TargetPython.get_tags for performance #12204

Commits on Aug 4, 2023