@matheusbsbs / matheus-bagliano / commits / 8e4ec3376e

merge-recursive: fix the diff3 common ancestor label for virtual commits

In commit 743474cbfa8b ("merge-recursive: provide a better label for diff3 common ancestor", 2019-08-17), the label for the common ancestor was changed from always being "merged common ancestors" to instead be based on the number of merge bases: >=2: "merged common ancestors" 1: <abbreviated commit hash> 0: "<empty tree>" Unfortunately, this did not take into account that when we have a single merge base, that merge base could be fake or constructed. In such cases, this resulted in a label of "00000000". Of course, the previous label of "merged common ancestors" was also misleading for this case. Since we have an API that is explicitly about creating fake merge base commits in merge_recursive_generic(), we should provide a better label when using that API with one merge base. So, when merge_recursive_generic() is called with one merge base, set the label to: "constructed merge base" Note that callers of merge_recursive_generic() include the builtin commands git-am (in combination with git apply --build-fake-ancestor), git-merge-recursive, and git-stash. Helped-by: Jeff King <peff@peff.net> Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Elijah Newren committed Oct 1, 2019 at 11:17 UTC 8e4ec3376e9d73bd471336cc7c11b35f5bc5dc87

2 files changed +19 -1

merge-recursive.c

+6 -1

@@ -3550,6 +3550,8 @@ static int merge_recursive_internal(struct merge_options *opt,

3550 merged_merge_bases = make_virtual_commit(opt->repo, tree,

3551 "ancestor");

3552 ancestor_name = "empty tree";

3553 + } else if (opt->ancestor) {

3554 + ancestor_name = opt->ancestor;

3555 } else if (merge_bases) {

3556 ancestor_name = "merged common ancestors";

3557 } else {

@@ -3689,7 +3691,8 @@ int merge_recursive(struct merge_options *opt,

3691 {

3692 int clean;

3693

3692 - assert(opt->ancestor == NULL);

3694 + assert(opt->ancestor == NULL ||

3695 + !strcmp(opt->ancestor, "constructed merge base"));

3696

3697 if (merge_start(opt, repo_get_commit_tree(opt->repo, h1)))

3698 return -1;

@@ -3741,6 +3744,8 @@ int merge_recursive_generic(struct merge_options *opt,

3744 oid_to_hex(merge_bases[i]));

3745 commit_list_insert(base, &ca);

3746 }

3747 + if (num_merge_bases == 1)

3748 + opt->ancestor = "constructed merge base";

3749 }

3750

3751 repo_hold_locked_index(opt->repo, &lock, LOCK_DIE_ON_ERROR);

t/t6047-diff3-conflict-markers.sh

+13

@@ -186,4 +186,17 @@ test_expect_success 'check multiple merge bases' '

186 )

187 '

188

189 +test_expect_success 'rebase describes fake ancestor base' '

190 + test_create_repo rebase &&

191 + (

192 + cd rebase &&

193 + test_commit base file &&

194 + test_commit master file &&

195 + git checkout -b side HEAD^ &&

196 + test_commit side file &&

197 + test_must_fail git -c merge.conflictstyle=diff3 rebase master &&

198 + grep "||||||| constructed merge base" file

199 + )

200 +'

201 +

202 test_done