From: Phillip Wood <phillip.wood@xxxxxxxxxxxxx>
Separate out calculating the merge base between onto and head from the
check for whether we can fast-forward or not. This means we can skip
the fast-forward checks when the rebase is forced and avoid
calculating the merge-base twice when --keep-base is given.
Signed-off-by: Phillip Wood <phillip.wood@xxxxxxxxxxxxx>
---
Note the unnecessary braces around "if (keep_base)" are added here
reduce the churn on the next commit.
---
builtin/rebase.c | 35 +++++++++++++++++++++++------------
1 file changed, 23 insertions(+), 12 deletions(-)
diff --git a/builtin/rebase.c b/builtin/rebase.c
index 6cf9c95f4e1..86ea731ca3a 100644
--- a/builtin/rebase.c
+++ b/builtin/rebase.c
@@ -871,13 +871,9 @@ static int can_fast_forward(struct commit *onto, struct commit *upstream,
struct commit_list *merge_bases = NULL;
int res = 0;
- merge_bases = get_merge_bases(onto, head);
- if (!merge_bases || merge_bases->next) {
- oidcpy(merge_base, null_oid());
+ if (is_null_oid(merge_base))
goto done;
- }
- oidcpy(merge_base, &merge_bases->item->object.oid);
if (!oideq(merge_base, &onto->object.oid))
goto done;
@@ -902,6 +898,20 @@ done:
return res && is_linear_history(onto, head);
}
+static void fill_merge_base(struct rebase_options *options,
+ struct object_id *merge_base)
+{
+ struct commit_list *merge_bases = NULL;
+
+ merge_bases = get_merge_bases(options->onto, options->orig_head);
+ if (!merge_bases || merge_bases->next)
+ oidcpy(merge_base, null_oid());
+ else
+ oidcpy(merge_base, &merge_bases->item->object.oid);
+
+ free_commit_list(merge_bases);
+}
+
static int parse_opt_am(const struct option *opt, const char *arg, int unset)
{
struct rebase_options *opts = opt->value;
@@ -1668,7 +1678,11 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
die(_("Does not point to a valid commit '%s'"),
options.onto_name);
}
-
+ if (keep_base) {
+ oidcpy(&merge_base, &options.onto->object.oid);
+ } else {
+ fill_merge_base(&options, &merge_base);
+ }
if (options.fork_point > 0)
options.restrict_revision =
get_fork_point(options.upstream_name, options.orig_head);
@@ -1697,13 +1711,10 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
* Check if we are already based on onto with linear history,
* in which case we could fast-forward without replacing the commits
* with new commits recreated by replaying their changes.
- *
- * Note that can_fast_forward() initializes merge_base, so we have to
- * call it before checking allow_preemptive_ff.
*/
- if (can_fast_forward(options.onto, options.upstream, options.restrict_revision,
- options.orig_head, &merge_base) &&
- allow_preemptive_ff) {
+ if (allow_preemptive_ff &&
+ can_fast_forward(options.onto, options.upstream, options.restrict_revision,
+ options.orig_head, &merge_base)) {
int flag;
if (!(options.flags & REBASE_FORCE)) {
--
gitgitgadget
