From: Elijah Newren <newren@xxxxxxxxx>
In the past, we dis-allowed rebases using the interactive backend from
performing a fast-forward to short-circuit the rebase operation. This
made sense for explicitly interactive rebases and some implicitly
interactive rebases, but certainly became overly stringent when the
merge backend was re-implemented via the interactive backend.
Just as the am-based rebase has always had to disable the fast-forward
based on a variety of conditions or flags (e.g. --signoff, --whitespace,
etc.), we need to do the same but now with a few more options. However,
continuing to use REBASE_FORCE for tracking this is problematic because
the interactive backend used it for a different purpose. (When
REBASE_FORCE wasn't set, the interactive backend would not fast-forward
the whole series but would fast-forward individual "pick" commits at the
beginning of the todo list, and then a squash or something would cause
it to start generating new commits.) So, introduce a new
allow_preemptive_ff flag contained within cmd_rebase() and use it to
track whether we are going to allow a pre-emptive fast-forward that
short-circuits the whole rebase.
Signed-off-by: Elijah Newren <newren@xxxxxxxxx>
---
builtin/rebase.c | 18 ++++++++++++++----
t/t3432-rebase-fast-forward.sh | 2 ++
2 files changed, 16 insertions(+), 4 deletions(-)
diff --git a/builtin/rebase.c b/builtin/rebase.c
index f1de5c8186..7027e34567 100644
--- a/builtin/rebase.c
+++ b/builtin/rebase.c
@@ -1493,6 +1493,7 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
struct object_id squash_onto;
char *squash_onto_name = NULL;
int reschedule_failed_exec = -1;
+ int allow_preemptive_ff = 1;
struct option builtin_rebase_options[] = {
OPT_STRING(0, "onto", &options.onto_name,
N_("revision"),
@@ -1804,11 +1805,18 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
options.ignore_date)
options.flags |= REBASE_FORCE;
+ if ((options.flags & REBASE_INTERACTIVE_EXPLICIT) ||
+ (action != ACTION_NONE) ||
+ (exec.nr > 0) ||
+ options.autosquash) {
+ allow_preemptive_ff = 0;
+ }
+
for (i = 0; i < options.git_am_opts.argc; i++) {
const char *option = options.git_am_opts.argv[i], *p;
if (!strcmp(option, "--whitespace=fix") ||
!strcmp(option, "--whitespace=strip"))
- options.flags |= REBASE_FORCE;
+ allow_preemptive_ff = 0;
else if (skip_prefix(option, "-C", &p)) {
while (*p)
if (!isdigit(*(p++)))
@@ -2144,12 +2152,14 @@ 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. This
- * optimization must not be done if this is an interactive rebase.
+ * 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) &&
- !is_interactive(&options)) {
+ allow_preemptive_ff) {
int flag;
if (!(options.flags & REBASE_FORCE)) {
diff --git a/t/t3432-rebase-fast-forward.sh b/t/t3432-rebase-fast-forward.sh
index 7432c0e241..40388ccf9f 100755
--- a/t/t3432-rebase-fast-forward.sh
+++ b/t/t3432-rebase-fast-forward.sh
@@ -30,6 +30,8 @@ test_rebase_same_head () {
shift &&
test_rebase_same_head_ $status_n $what_n $cmp_n "" "$*" &&
test_rebase_same_head_ $status_f $what_f $cmp_f " --no-ff" "$*"
+ test_rebase_same_head_ $status_n $what_n $cmp_n " --merge" "$*" &&
+ test_rebase_same_head_ $status_f $what_f $cmp_f " --merge --no-ff" "$*"
}
test_rebase_same_head_ () {
--
gitgitgadget
