Re: [PATCH] pull: abort if --ff-only is given and fast-forwarding is impossible
From: Phillip Wood <hidden>
Date: 2021-07-12 10:21:10
Hi Alex On 11/07/2021 02:26, Alex Henrie wrote:
The warning about pulling without specifying how to reconcile divergent branches says that after setting pull.rebase to true, --ff-only can still be passed on the command line to require a fast-forward. Make that actually work.
Thanks for revising this patch, I like this approach much better. I do
however have some concerns about the interaction of pull.ff with the
rebase config and command line options. I'd naively expect the following
behavior (where rebase can fast-forward if possible)
pull.ff pull.rebase commandline action
only not false rebase
only not false --no-rebase fast-forward only
* not false --ff-only fast-forward only
only not false --ff merge --ff
only not false --no-ff merge --no-ff
only false fast-forward only
only false --rebase rebase
only false --ff merge --ff
only false --no-ff merge --no-ff
I don't think enforcing fast-forward only for rebases makes sense unless
it is given on the command line. If the user gives `--rebase`
`--ff-only` on the command line then we should either error out or take
the last one in which case `pull --rebase --ff-only` would fast-forward
only but `pull --ff-only --rebase` would rebase. We should also decide
what to do when the user has pull.ff set to something other than only
and also has pull.rebase to something other than false set - I'd guess
we'd want to rebase unless there is a merge option on the command line
but I haven't thought about those cases.
Best Wishes
Phillip
quoted hunk ↗ jump to hunk
Signed-off-by: Alex Henrie <redacted> --- advice.c | 5 +++++ advice.h | 1 + builtin/merge.c | 2 +- builtin/pull.c | 11 ++++++++--- t/t7601-merge-pull-config.sh | 24 ++++++++++++++++++++++++ 5 files changed, 39 insertions(+), 4 deletions(-)diff --git a/advice.c b/advice.c index 0b9c89c48a..337e8f342b 100644 --- a/advice.c +++ b/advice.c@@ -286,6 +286,11 @@ void NORETURN die_conclude_merge(void) die(_("Exiting because of unfinished merge.")); } +void NORETURN die_ff_impossible(void) +{ + die(_("Not possible to fast-forward, aborting.")); +} + void advise_on_updating_sparse_paths(struct string_list *pathspec_list) { struct string_list_item *item;diff --git a/advice.h b/advice.h index bd26c385d0..1624043838 100644 --- a/advice.h +++ b/advice.h@@ -95,6 +95,7 @@ void advise_if_enabled(enum advice_type type, const char *advice, ...); int error_resolve_conflict(const char *me); void NORETURN die_resolve_conflict(const char *me); void NORETURN die_conclude_merge(void); +void NORETURN die_ff_impossible(void); void advise_on_updating_sparse_paths(struct string_list *pathspec_list); void detach_advice(const char *new_name);diff --git a/builtin/merge.c b/builtin/merge.c index a8a843b1f5..aa920ac524 100644 --- a/builtin/merge.c +++ b/builtin/merge.c@@ -1620,7 +1620,7 @@ int cmd_merge(int argc, const char **argv, const char *prefix) } if (fast_forward == FF_ONLY) - die(_("Not possible to fast-forward, aborting.")); + die_ff_impossible(); if (autostash) create_autostash(the_repository,diff --git a/builtin/pull.c b/builtin/pull.c index 3e13f81084..d979660482 100644 --- a/builtin/pull.c +++ b/builtin/pull.c@@ -1046,9 +1046,14 @@ int cmd_pull(int argc, const char **argv, const char *prefix) can_ff = get_can_ff(&orig_head, &merge_heads.oid[0]); - if (rebase_unspecified && !opt_ff && !can_ff) { - if (opt_verbosity >= 0) - show_advice_pull_non_ff(); + 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(); + } } if (opt_rebase) {diff --git a/t/t7601-merge-pull-config.sh b/t/t7601-merge-pull-config.sh index 52e8ccc933..b5a09a60f9 100755 --- a/t/t7601-merge-pull-config.sh +++ b/t/t7601-merge-pull-config.sh@@ -183,6 +183,30 @@ test_expect_success 'pull prevents non-fast-forward with "only" in pull.ff' ' test_must_fail git pull . c3 ' +test_expect_success 'pull prevents non-fast-forward with pull.ff=only and pull.rebase=true' ' + git reset --hard c1 && + test_config pull.ff only && + test_config pull.rebase true && + test_must_fail git pull . c3 +' + +test_expect_success 'pull prevents non-fast-forward with pull.ff=only and pull.rebase=false' ' + git reset --hard c1 && + test_config pull.ff only && + test_config pull.rebase false && + test_must_fail git pull . c3 +' + +test_expect_success 'pull prevents non-fast-forward with --rebase --ff-only' ' + git reset --hard c1 && + test_must_fail git pull --rebase --ff-only . c3 +' + +test_expect_success 'pull prevents non-fast-forward with --no-rebase --ff-only' ' + git reset --hard c1 && + test_must_fail git pull --no-rebase --ff-only . c3 +' + test_expect_success 'merge c1 with c2 (ours in pull.twohead)' ' git reset --hard c1 && git config pull.twohead ours &&