pull: since --ff-only overrides, handle it first

There are both merge and rebase branches in the logic, and previously
both had to handle fast-forwarding.  Merge handled that implicitly
(because git merge handles it directly), while in rebase it was
explicit.  Given that the --ff-only flag is meant to override any
--rebase or --no-rebase, make the code reflect that by handling
--ff-only before the merge-vs-rebase logic.

It turns out that this also fixes a bug for submodules.  Previously,
when --ff-only was given, the code would run `merge --ff-only` on the
main module, and then run `submodule update --recursive --rebase` on the
submodules.  With this change, we still run `merge --ff-only` on the
main module, but now run `submodule update --recursive --checkout` on
the submodules.  I believe this better reflects the intent of --ff-only
to have it apply to both the main module and the submodules.

(Sidenote: It is somewhat interesting that all merges pass `--checkout`
to submodule update, even when `--no-ff` is specified, meaning that it
will only do fast-forward merges for submodules.  This was discussed in
commit a6d7eb2c7a ("pull: optionally rebase submodules (remote submodule
changes only)", 2017-06-23).  The same limitations apply now as then, so
we are not trying to fix this at this time.)

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Elijah Newren 2021-07-22 05:04:46 +00:00 committed by Junio C Hamano
parent 3d5fc24dae
commit e4dc25ed49

View File

@ -1046,15 +1046,15 @@ int cmd_pull(int argc, const char **argv, const char *prefix)
can_ff = get_can_ff(&orig_head, &merge_heads.oid[0]);
if (!can_ff) {
if (opt_ff) {
if (!strcmp(opt_ff, "--ff-only"))
die_ff_impossible();
} else {
if (rebase_unspecified && opt_verbosity >= 0)
show_advice_pull_non_ff();
}
/* ff-only takes precedence over rebase */
if (opt_ff && !strcmp(opt_ff, "--ff-only")) {
if (!can_ff)
die_ff_impossible();
opt_rebase = REBASE_FALSE;
}
/* If no action specified and we can't fast forward, then warn. */
if (!opt_ff && rebase_unspecified && !can_ff)
show_advice_pull_non_ff();
if (opt_rebase) {
int ret = 0;