gh-119105: difflib.py Differ.compare is too slow [for degenerate cases]#119376
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tim-one merged 5 commits intopython:mainfrom May 22, 2024
Merged
gh-119105: difflib.py Differ.compare is too slow [for degenerate cases]#119376tim-one merged 5 commits intopython:mainfrom
tim-one merged 5 commits intopython:mainfrom
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Jul 17, 2024
…e cases] (python#119376) Track all pairs achieving the best ratio in Differ(). This repairs the "very deep recursion and cubic time" bad cases in a way that preserves previous output.
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A different approach, tracking all ascending index pairs achieving the best ratio. None of them needs recursion then. And, more importantly, it restores difflib's general "top to bottom" ordering of matches.