diff options
-rw-r--r-- | merge-base.c | 78 |
1 files changed, 77 insertions, 1 deletions
diff --git a/merge-base.c b/merge-base.c index 286bf0e8d..43a681836 100644 --- a/merge-base.c +++ b/merge-base.c @@ -80,6 +80,45 @@ static struct commit *interesting(struct commit_list *list) * Now, list does not have any interesting commit. So we find the newest * commit from the result list that is not marked uninteresting. Which is * commit B. + * + * + * Another pathological example how this thing can fail to mark an ancestor + * of a merge base as UNINTERESTING without the postprocessing phase. + * + * 2 + * H + * 1 / \ + * G A \ + * |\ / \ + * | B \ + * | \ \ + * \ C F + * \ \ / + * \ D / + * \ | / + * \| / + * E + * + * list A B C D E F G H + * G1 H2 - - - - - - 1 2 + * H2 E1 B1 - 1 - - 1 - 1 2 + * F2 E1 B1 A2 2 1 - - 1 2 1 2 + * E3 B1 A2 2 1 - - 3 2 1 2 + * B1 A2 2 1 - - 3 2 1 2 + * C1 A2 2 1 1 - 3 2 1 2 + * D1 A2 2 1 1 1 3 2 1 2 + * A2 2 1 1 1 3 2 1 2 + * B3 2 3 1 1 3 2 1 2 + * C7 2 3 7 1 3 2 1 2 + * + * At this point, unfortunately, everybody in the list is + * uninteresting, so we fail to complete the following two + * steps to fully marking uninteresting commits. + * + * D7 2 3 7 7 3 2 1 2 + * E7 2 3 7 7 7 2 1 2 + * + * and we end up showing E as an interesting merge base. */ static int show_all = 0; @@ -88,6 +127,7 @@ static int merge_base(struct commit *rev1, struct commit *rev2) { struct commit_list *list = NULL; struct commit_list *result = NULL; + struct commit_list *tmp = NULL; if (rev1 == rev2) { printf("%s\n", sha1_to_hex(rev1->object.sha1)); @@ -104,9 +144,10 @@ static int merge_base(struct commit *rev1, struct commit *rev2) while (interesting(list)) { struct commit *commit = list->item; - struct commit_list *tmp = list, *parents; + struct commit_list *parents; int flags = commit->object.flags & 7; + tmp = list; list = list->next; free(tmp); if (flags == 3) { @@ -130,6 +171,41 @@ static int merge_base(struct commit *rev1, struct commit *rev2) if (!result) return 1; + /* + * Postprocess to fully contaminate the well. + */ + for (tmp = result; tmp; tmp = tmp->next) { + struct commit *c = tmp->item; + /* Reinject uninteresting ones to list, + * so we can scan their parents. + */ + if (c->object.flags & UNINTERESTING) + commit_list_insert(c, &list); + } + while (list) { + struct commit *c = list->item; + struct commit_list *parents; + + tmp = list; + list = list->next; + free(tmp); + + /* Anything taken out of the list is uninteresting, so + * mark all its parents uninteresting. We do not + * parse new ones (we already parsed all the relevant + * ones). + */ + parents = c->parents; + while (parents) { + struct commit *p = parents->item; + parents = parents->next; + if (!(p->object.flags & UNINTERESTING)) { + p->object.flags |= UNINTERESTING; + commit_list_insert(p, &list); + } + } + } + while (result) { struct commit *commit = result->item; result = result->next; |