Add sort before groupby#31
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itertools.groupby only groups consecutive equal keys, so unordered matches reaching _group_by_match_index split into separate groups and the dict assignment overwrites earlier ones, silently dropping matches. Sort by match_index first (no-op when already ordered), matching the sorted()-before-groupby() convention in rules.py. Reworked from #31 (rebased, line wrapped, typed test that fails without the fix). Supersedes #31. Co-authored-by: denini08 <denini08@users.noreply.github.com>
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Thanks a lot for catching this, @denini08 — you're absolutely right that I've merged a reworked version in #49 (rebased on the current Closing this one in favour of #49 — much appreciated! 🙏 |
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Hello!
While reading the code and running some tests, I noticed a small detail that could cause unexpected behavior when the input list is not ordered. The
itertools.groupby()function assumes the data is already sorted by the key (docs), but in_group_by_match_indexthis was not guaranteed.So I added a
sorted()call before thegroupby()to make the behavior safe and consistent, regardless of the input order.Interestingly, the rest of the codebase already follows this same pattern:
sorted()beforegroupby()I also added a small test that explicitly checks the behavior with unsorted input data, just to make sure this case is always covered.
Thank youfor the project!
I hope this improvement is helpful.