From: Elijah Newren <newren@xxxxxxxxx>
With multiple heads, we should not allow rebasing or fast-forwarding.
Make sure any fast-forward request calls out specifically the fact that
multiple branches are in play. Also, since we cannot fast-forward to
multiple branches, fix our computation of can_ff.
Signed-off-by: Elijah Newren <newren@xxxxxxxxx>
---
builtin/pull.c | 18 ++++++++++++++----
t/t7601-merge-pull-config.sh | 2 +-
2 files changed, 15 insertions(+), 5 deletions(-)
diff --git a/builtin/pull.c b/builtin/pull.c
index 2f1d1f4037d..b311ea6b9df 100644
--- a/builtin/pull.c
+++ b/builtin/pull.c
@@ -913,12 +913,18 @@ static int run_rebase(const struct object_id *newbase,
return ret;
}
-static int get_can_ff(struct object_id *orig_head, struct object_id *orig_merge_head)
+static int get_can_ff(struct object_id *orig_head,
+ struct oid_array *merge_heads)
{
int ret;
struct commit_list *list = NULL;
struct commit *merge_head, *head;
+ struct object_id *orig_merge_head;
+ if (merge_heads->nr > 1)
+ return 0;
+
+ orig_merge_head = &merge_heads->oid[0];
head = lookup_commit_reference(the_repository, orig_head);
commit_list_insert(head, &list);
merge_head = lookup_commit_reference(the_repository, orig_merge_head);
@@ -1057,10 +1063,14 @@ int cmd_pull(int argc, const char **argv, const char *prefix)
die(_("Cannot merge multiple branches into empty head."));
return pull_into_void(merge_heads.oid, &curr_head);
}
- if (opt_rebase && merge_heads.nr > 1)
- die(_("Cannot rebase onto multiple branches."));
+ if (merge_heads.nr > 1) {
+ if (opt_rebase)
+ die(_("Cannot rebase onto multiple branches."));
+ if (opt_ff && !strcmp(opt_ff, "--ff-only"))
+ die(_("Cannot fast-forward to multiple branches."));
+ }
- can_ff = get_can_ff(&orig_head, &merge_heads.oid[0]);
+ can_ff = get_can_ff(&orig_head, &merge_heads);
/* ff-only takes precedence over rebase */
if (opt_ff && !strcmp(opt_ff, "--ff-only")) {
diff --git a/t/t7601-merge-pull-config.sh b/t/t7601-merge-pull-config.sh
index 742ed3981c7..1f652f433ee 100755
--- a/t/t7601-merge-pull-config.sh
+++ b/t/t7601-merge-pull-config.sh
@@ -331,7 +331,7 @@ test_expect_success 'Multiple heads warns about inability to fast forward' '
test_i18ngrep "You have divergent branches" err
'
-test_expect_failure 'Multiple can never be fast forwarded' '
+test_expect_success 'Multiple can never be fast forwarded' '
git reset --hard c0 &&
test_must_fail git -c pull.ff=only pull . c1 c2 c3 2>err &&
test_i18ngrep ! "You have divergent branches" err &&
--
gitgitgadget
