commit: use generations in paint_down_to_common()

diff --git a/commit.c b/commit.c
index 711f674c18d00c8d62b117764e67c5d9c6731616..4d00b0a1d6d7c9eb4c331a79c2172844aad854db 100644 (file)
--- a/commit.c
+++ b/commit.c
@@ -640,6 +640,24 @@ static int compare_commits_by_author_date(const void *a_, const void *b_,
        return 0;
 }
 
+int compare_commits_by_gen_then_commit_date(const void *a_, const void *b_, void *unused)
+{
+       const struct commit *a = a_, *b = b_;
+
+       /* newer commits first */
+       if (a->generation < b->generation)
+               return 1;
+       else if (a->generation > b->generation)
+               return -1;
+
+       /* use date as a heuristic when generations are equal */
+       if (a->date < b->date)
+               return 1;
+       else if (a->date > b->date)
+               return -1;
+       return 0;
+}
+
 int compare_commits_by_commit_date(const void *a_, const void *b_, void *unused)
 {
        const struct commit *a = a_, *b = b_;
@@ -789,7 +807,7 @@ static int queue_has_nonstale(struct prio_queue *queue)
 /* all input commits in one and twos[] must have been parsed! */
 static struct commit_list *paint_down_to_common(struct commit *one, int n, struct commit **twos)
 {
-       struct prio_queue queue = { compare_commits_by_commit_date };
+       struct prio_queue queue = { compare_commits_by_gen_then_commit_date };
        struct commit_list *result = NULL;
        int i;