path: root/t/
diff options
authorDenton Liu <>2019-08-27 05:37:59 (GMT)
committerJunio C Hamano <>2019-08-27 22:33:40 (GMT)
commitc0efb4c1ddccf91dedd5775f2f449574e90b051a (patch)
tree5d5766724458697a352396162fa806dd7f12cbdb /t/
parent2b318aa6c3566ad65d9547f42828f277955e6519 (diff)
rebase: fast-forward --onto in more cases
Before, when we had the following graph, A---B---C (master) \ D (side) running 'git rebase --onto master... master side' would result in D being always rebased, no matter what. However, the desired behavior is that rebase should notice that this is fast-forwardable and do that instead. Add detection to `can_fast_forward` so that this case can be detected and a fast-forward will be performed. First of all, rewrite the function to use gotos which simplifies the logic. Next, since the options.upstream && !oidcmp(&options.upstream->object.oid, &options.onto->object.oid) conditions were removed in `cmd_rebase`, we reintroduce a substitute in `can_fast_forward`. In particular, checking the merge bases of `upstream` and `head` fixes a failing case in t3416. The abbreviated graph for t3416 is as follows: F---G topic / A---B---C---D---E master and the failing command was git rebase --onto master...topic F topic Before, Git would see that there was one merge base (C), and the merge and onto were the same so it would incorrectly return 1, indicating that we could fast-forward. This would cause the rebased graph to be 'ABCFG' when we were expecting 'ABCG'. With the additional logic, we detect that upstream and head's merge base is F. Since onto isn't F, it means we're not rebasing the full set of commits from master..topic. Since we're excluding some commits, a fast-forward cannot be performed and so we correctly return 0. Add '-f' to test cases that failed as a result of this change because they were not expecting a fast-forward so that a rebase is forced. Helped-by: Phillip Wood <> Signed-off-by: Denton Liu <> Signed-off-by: Junio C Hamano <>
Diffstat (limited to 't/')
1 files changed, 1 insertions, 1 deletions
diff --git a/t/ b/t/
index 461dd53..3cc9052 100755
--- a/t/
+++ b/t/
@@ -1058,7 +1058,7 @@ test_expect_success C_LOCALE_OUTPUT 'rebase --edit-todo does not work on non-int
git reset --hard &&
git checkout conflict-branch &&
set_fake_editor &&
- test_must_fail git rebase --onto HEAD~2 HEAD~ &&
+ test_must_fail git rebase -f --onto HEAD~2 HEAD~ &&
test_must_fail git rebase --edit-todo &&
git rebase --abort