From: kristofferhaugsbakk@fastmail.com Date: Tue, 30 Dec 2025 15:01:49 GMT Subject: [PATCH v2 3/5] replay: die descriptively when invalid commit-ish is given Message-ID: In-Reply-To: From: Kristoffer Haugsbakk Giving an invalid commit-ish to `--onto` makes git-replay(1) fail with: fatal: Replaying down to root commit is not supported yet! Going backwards from this point: 1. `onto` is `NULL` from `determine_replay_mode`; 2. that function in turn calls `peel_committish`; and 3. here we return `NULL` if `repo_get_oid` fails. Let’s die immediately with a descriptive error message instead. Doing this also provides us with a descriptive error if we “forget” to provide an argument to `--onto` (but we really do unintentionally):[1] $ git replay --onto ^main topic1 fatal: '^main' is not a valid commit-ish Note that the `--advance` case won’t be triggered in practice because of the “argument to --advance must be a reference” check (see the previous test, and commit). † 1: The argument to `--onto` is mandatory and the option parser accepts both `--onto=` (stuck form) and `--onto name`. The latter form makes it easy to unintentionally pass something to the option when you really meant to pass a positional argument. Signed-off-by: Kristoffer Haugsbakk --- Notes (series): v2: Let’s use a slightly longer subject line in the commit message so that it looks more like a full sentence (no dropped/implied words).[1] Also remove the test for `--advance` which is now wrong because of the previous commit/patch. And reword the commit message now that only `--onto` is relevant in practice. There was also feedback about *where* to give this error:[2] > How many callers use this function? I am wondering if it is better > to give a better message at the caller(s), rather than here, where > we lack context to tell something like "You gave string 'ource' as > the argument to the '--onto' option, but 'ource' does not name any > commit" (in other words, "for what our caller is trying to peel > to a commit"). But I opted to keep the check here by using the new `mode` parameter to provide the context; it is either `--onto` or `--advance`. Also remove the “not supported yet” now that `*onto` cannot be `NULL` at this point. I wasn’t confident enough to pull the trigger on that in the first round. But after Elijah’s comment[3] I feel like I understand the code well enough. Also change the test to use printf since it’s only one line. That will be in line with the later commits/patches here. 🔗 1: https://lore.kernel.org/git/xmqqecolrip7.fsf@gitster.g/ 🔗 2: https://lore.kernel.org/git/xmqqikdxriw3.fsf@gitster.g/ 🔗 3: https://lore.kernel.org/git/CABPp-BEcJqjD4ztsZo2FTZgWT5ZOADKYEyiZtda+d0mSd1quPQ@mail.gmail.com/ builtin/replay.c | 15 +++++++-------- t/t3650-replay-basics.sh | 7 +++++++ 2 files changed, 14 insertions(+), 8 deletions(-) diff --git a/builtin/replay.c b/builtin/replay.c index 35813140e99..07a6767ade1 100644 --- a/builtin/replay.c +++ b/builtin/replay.c @@ -25,17 +25,19 @@ static const char *short_commit_name(struct repository *repo, { return repo_find_unique_abbrev(repo, &commit->object.oid, DEFAULT_ABBREV); } -static struct commit *peel_committish(struct repository *repo, const char *name) +static struct commit *peel_committish(struct repository *repo, + const char *name, + const char *mode) { struct object *obj; struct object_id oid; if (repo_get_oid(repo, name, &oid)) - return NULL; + die(_("'%s' is not a valid commit-ish for %s"), name, mode); obj = parse_object(repo, &oid); return (struct commit *)repo_peel_to_type(repo, name, 0, obj, OBJ_COMMIT); } @@ -170,11 +172,11 @@ static void populate_for_onto_or_advance_mode(struct repository *repo, die(_("need some commits to replay")); die_for_incompatible_opt2(!!onto_name, "--onto", !!*advance_name, "--advance"); if (onto_name) { - *onto = peel_committish(repo, onto_name); + *onto = peel_committish(repo, onto_name, "--onto"); if (rinfo.positive_refexprs < strset_get_size(&rinfo.positive_refs)) die(_("all positive revisions given must be references")); *update_refs = xcalloc(1, sizeof(**update_refs)); **update_refs = rinfo.positive_refs; @@ -191,11 +193,11 @@ static void populate_for_onto_or_advance_mode(struct repository *repo, free(*advance_name); *advance_name = fullname; } else { die(_("argument to --advance must be a reference")); } - *onto = peel_committish(repo, *advance_name); + *onto = peel_committish(repo, *advance_name, "--advance"); if (rinfo.positive_refexprs > 1) die(_("cannot advance target with multiple sources because ordering would be ill-defined")); } strset_clear(&rinfo.negative_refs); strset_clear(&rinfo.positive_refs); @@ -349,13 +351,10 @@ int cmd_replay(int argc, populate_for_onto_or_advance_mode(repo, &revs.cmdline, onto_name, &advance_name, &onto, &update_refs); - if (!onto) /* FIXME: Should handle replaying down to root commit */ - die("Replaying down to root commit is not supported yet!"); - if (prepare_revision_walk(&revs) < 0) { ret = error(_("error preparing revisions")); goto cleanup; } @@ -367,11 +366,11 @@ int cmd_replay(int argc, while ((commit = get_revision(&revs))) { const struct name_decoration *decoration; khint_t pos; int hr; - if (!commit->parents) + if (!commit->parents) /* FIXME: Should handle replaying down to root commit */ die(_("replaying down to root commit is not supported yet!")); if (commit->parents->next) die(_("replaying merge commits is not supported yet!")); last_commit = pick_regular_commit(repo, commit, replayed_commits, diff --git a/t/t3650-replay-basics.sh b/t/t3650-replay-basics.sh index 7dea62f064f..d4399aa1662 100755 --- a/t/t3650-replay-basics.sh +++ b/t/t3650-replay-basics.sh @@ -56,10 +56,17 @@ test_expect_success 'argument to --advance must be a reference' ' oid=$(git rev-parse main) && test_must_fail git replay --advance=$oid topic1..topic2 2>actual && test_cmp expect actual ' +test_expect_success '--onto with invalid commit-ish' ' + printf "fatal: ${SQ}refs/not-valid${SQ} is not " >expect && + printf "a valid commit-ish for --onto\n" >>expect && + test_must_fail git replay --onto=refs/not-valid topic1..topic2 2>actual && + test_cmp expect actual +' + test_expect_success 'using replay to rebase two branches, one on top of other' ' git replay --onto main topic1..topic2 >result && test_line_count = 1 result && -- 2.52.0.10.g08704017180