Subtype checking micro-optimization #19384
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Speeds up self-check by about 0.6%. The assertion is very hot, and the original version always created a set, which is slow.
| According to mypy_primer, this change doesn't affect type check results on a corpus of open source code. ✅ |
JelleZijlstra approved these changes Jul 6, 2025
hauntsaninja approved these changes Jul 6, 2025
| There's an assert of exactly same form in |
| @sterliakov Yes, that one should be rewritten as well (it is probably less hot, but still worth doing). |
JukkaL added a commit that referenced this pull request Jul 16, 2025
…#19463) This was suggested by @sterliakov in #19384 (comment) This is a part of a set of micro-optimizations that improve self check performance by ~5.5%.
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Speeds up self-check by about 0.6%. The assertion is very hot, and the original version always created a set, which is slow.