From df534dcbaafa74be9e922418712bede75676588b Mon Sep 17 00:00:00 2001 From: Johannes Schindelin Date: Thu, 14 Jul 2022 15:43:49 +0000 Subject: [PATCH] shortlog: use a stable sort When sorting the output of `git shortlog` by count, a list of authors in alphabetical order is then sorted by contribution count. Obviously, the idea is to maintain the alphabetical order for items with identical contribution count. At the moment, this job is performed by `qsort()`. As that function is not guaranteed to implement a stable sort algorithm, this can lead to inconsistent and/or surprising behavior: items with identical contribution count could lose their alphabetical sub-order. The `qsort()` in MS Visual C's runtime does _not_ implement a stable sort algorithm, and under certain circumstances this even causes a test failure in t4201.21 "shortlog can match multiple groups", where two authors both are listed with 2 contributions, and are listed in inverse alphabetical order. Let's instead use the stable sort provided by `git_stable_qsort()` to avoid this inconsistency. This is a companion to 2049b8dc65 (diffcore_rename(): use a stable sort, 2019-09-30). Signed-off-by: Johannes Schindelin Signed-off-by: Junio C Hamano --- builtin/shortlog.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/builtin/shortlog.c b/builtin/shortlog.c index 35825f075e..086dfee45a 100644 --- a/builtin/shortlog.c +++ b/builtin/shortlog.c @@ -443,7 +443,7 @@ void shortlog_output(struct shortlog *log) struct strbuf sb = STRBUF_INIT; if (log->sort_by_number) - QSORT(log->list.items, log->list.nr, + STABLE_QSORT(log->list.items, log->list.nr, log->summary ? compare_by_counter : compare_by_list); for (i = 0; i < log->list.nr; i++) { const struct string_list_item *item = &log->list.items[i];