Merge branch 'tc/replay-ref'

The experimental `git replay` command learned the `--ref=<ref>` option
to allow specifying which ref to update, overriding the default behavior.

* tc/replay-ref:
  replay: allow to specify a ref with option --ref
  replay: use stuck form in documentation and help message
  builtin/replay: mark options as not negatable

5 files changed, 157 insertions, 34 deletions

diff --git a/Documentation/git-replay.adoc b/Documentation/git-replay.adoc
index 997097e420..a32f72aead 100644
--- a/Documentation/git-replay.adoc
+++ b/Documentation/git-replay.adoc
@@ -9,7 +9,8 @@ git-replay - EXPERIMENTAL: Replay commits on a new base, works with bare repos t
 SYNOPSIS
 --------
 [verse]
-(EXPERIMENTAL!) 'git replay' ([--contained] --onto <newbase> | --advance <branch> | --revert <branch>) [--ref-action[=<mode>]] <revision-range>
+(EXPERIMENTAL!) 'git replay' ([--contained] --onto=<newbase> | --advance=<branch> | --revert=<branch>)
+			     [--ref=<ref>] [--ref-action=<mode>] <revision-range>
 
 DESCRIPTION
 -----------
@@ -26,7 +27,7 @@ THIS COMMAND IS EXPERIMENTAL. THE BEHAVIOR MAY CHANGE.
 OPTIONS
 -------
 
---onto <newbase>::
+--onto=<newbase>::
 	Starting point at which to create the new commits.  May be any
 	valid commit, and not just an existing branch name.
 +
@@ -34,7 +35,7 @@ When `--onto` is specified, the branch(es) in the revision range will be
 updated to point at the new commits, similar to the way `git rebase --update-refs`
 updates multiple branches in the affected range.
 
---advance <branch>::
+--advance=<branch>::
 	Starting point at which to create the new commits; must be a
 	branch name.
 +
@@ -42,7 +43,7 @@ The history is replayed on top of the <branch> and <branch> is updated to
 point at the tip of the resulting history. This is different from `--onto`,
 which uses the target only as a starting point without updating it.
 
---revert <branch>::
+--revert=<branch>::
 	Starting point at which to create the reverted commits; must be a
 	branch name.
 +
@@ -65,6 +66,16 @@ incompatible with `--contained` (which is a modifier for `--onto` only).
 	Update all branches that point at commits in
 	<revision-range>. Requires `--onto`.
 
+--ref=<ref>::
+	Override which reference is updated with the result of the replay.
+	The ref must be fully qualified.
+	When used with `--onto`, the `<revision-range>` should have a
+	single tip and only the specified reference is updated instead of
+	inferring refs from the revision range.
+	When used with `--advance` or `--revert`, the specified reference is
+	updated instead of the branch given to those options.
+	This option is incompatible with `--contained`.
+
 --ref-action[=<mode>]::
 	Control how references are updated. The mode can be:
 +
@@ -79,8 +90,8 @@ The default mode can be configured via the `replay.refAction` configuration vari
 
 <revision-range>::
 	Range of commits to replay; see "Specifying Ranges" in
-	linkgit:git-rev-parse[1]. In `--advance <branch>` or
-	`--revert <branch>` mode, the range should have a single tip,
+	linkgit:git-rev-parse[1]. In `--advance=<branch>` or
+	`--revert=<branch>` mode, the range should have a single tip,
 	so that it's clear to which tip the advanced or reverted
 	<branch> should point. Any commits in the range whose changes
 	are already present in the branch the commits are being
@@ -127,7 +138,7 @@ EXAMPLES
 To simply rebase `mybranch` onto `target`:
 
 ------------
-$ git replay --onto target origin/main..mybranch
+$ git replay --onto=target origin/main..mybranch
 ------------
 
 The refs are updated atomically and no output is produced on success.
@@ -135,14 +146,14 @@ The refs are updated atomically and no output is produced on success.
 To see what would be updated without actually updating:
 
 ------------
-$ git replay --ref-action=print --onto target origin/main..mybranch
+$ git replay --ref-action=print --onto=target origin/main..mybranch
 update refs/heads/mybranch ${NEW_mybranch_HASH} ${OLD_mybranch_HASH}
 ------------
 
 To cherry-pick the commits from mybranch onto target:
 
 ------------
-$ git replay --advance target origin/main..mybranch
+$ git replay --advance=target origin/main..mybranch
 ------------
 
 Note that the first two examples replay the exact same commits and on
@@ -154,7 +165,7 @@ What if you have a stack of branches, one depending upon another, and
 you'd really like to rebase the whole set?
 
 ------------
-$ git replay --contained --onto origin/main origin/main..tipbranch
+$ git replay --contained --onto=origin/main origin/main..tipbranch
 ------------
 
 All three branches (`branch1`, `branch2`, and `tipbranch`) are updated
@@ -165,7 +176,7 @@ commits to replay using the syntax `A..B`; any range expression will
 do:
 
 ------------
-$ git replay --onto origin/main ^base branch1 branch2 branch3
+$ git replay --onto=origin/main ^base branch1 branch2 branch3
 ------------
 
 This will simultaneously rebase `branch1`, `branch2`, and `branch3`,
@@ -176,7 +187,7 @@ that they have in common, but that does not need to be the case.
 To revert commits on a branch:
 
 ------------
-$ git replay --revert main topic~2..topic
+$ git replay --revert=main topic~2..topic
 ------------
 
 This reverts the last two commits from `topic`, creating revert commits on
@@ -188,6 +199,16 @@ NOTE: For reverting an entire merge request as a single commit (rather than
 commit-by-commit), consider using `git merge-tree --merge-base $TIP HEAD $BASE`
 which can avoid unnecessary merge conflicts.
 
+To replay onto a specific commit while updating a different reference:
+
+------------
+$ git replay --onto=112233 --ref=refs/heads/mybranch aabbcc..ddeeff
+------------
+
+This replays the range `aabbcc..ddeeff` onto commit `112233` and updates
+`refs/heads/mybranch` to point at the result. This can be useful when you want
+to use bare commit IDs instead of branch names.
+
 GIT
 ---
 Part of the linkgit:git[1] suite
diff --git a/builtin/replay.c b/builtin/replay.c
index a0879b020f..39e3a86f6c 100644
--- a/builtin/replay.c
+++ b/builtin/replay.c
@@ -84,25 +84,33 @@ int cmd_replay(int argc,
 
 	const char *const replay_usage[] = {
 		N_("(EXPERIMENTAL!) git replay "
-		   "([--contained] --onto <newbase> | --advance <branch> | --revert <branch>) "
-		   "[--ref-action[=<mode>]] <revision-range>"),
+		   "([--contained] --onto=<newbase> | --advance=<branch> | --revert=<branch>)\n"
+		   "[--ref=<ref>] [--ref-action=<mode>] <revision-range>"),
 		NULL
 	};
 	struct option replay_options[] = {
-		OPT_STRING(0, "advance", &opts.advance,
-			   N_("branch"),
-			   N_("make replay advance given branch")),
-		OPT_STRING(0, "onto", &opts.onto,
-			   N_("revision"),
-			   N_("replay onto given commit")),
 		OPT_BOOL(0, "contained", &opts.contained,
 			 N_("update all branches that point at commits in <revision-range>")),
-		OPT_STRING(0, "revert", &opts.revert,
-			   N_("branch"),
-			   N_("revert commits onto given branch")),
-		OPT_STRING(0, "ref-action", &ref_action,
-			   N_("mode"),
-			   N_("control ref update behavior (update|print)")),
+		OPT_STRING_F(0, "onto", &opts.onto,
+			     N_("revision"),
+			     N_("replay onto given commit"),
+			     PARSE_OPT_NONEG),
+		OPT_STRING_F(0, "advance", &opts.advance,
+			     N_("branch"),
+			     N_("make replay advance given branch"),
+			     PARSE_OPT_NONEG),
+		OPT_STRING_F(0, "revert", &opts.revert,
+			     N_("branch"),
+			     N_("revert commits onto given branch"),
+			     PARSE_OPT_NONEG),
+		OPT_STRING_F(0, "ref", &opts.ref,
+			     N_("branch"),
+			     N_("reference to update with result"),
+			     PARSE_OPT_NONEG),
+		OPT_STRING_F(0, "ref-action", &ref_action,
+			     N_("mode"),
+			     N_("control ref update behavior (update|print)"),
+			     PARSE_OPT_NONEG),
 		OPT_END()
 	};
 
@@ -122,6 +130,8 @@ int cmd_replay(int argc,
 				  opts.contained, "--contained");
 	die_for_incompatible_opt2(!!opts.revert, "--revert",
 				  opts.contained, "--contained");
+	die_for_incompatible_opt2(!!opts.ref, "--ref",
+				  !!opts.contained, "--contained");
 
 	/* Parse ref action mode from command line or config */
 	ref_mode = get_ref_action_mode(repo, ref_action);
diff --git a/replay.c b/replay.c
index cf1f0bcba0..f96f1f6551 100644
--- a/replay.c
+++ b/replay.c
@@ -358,13 +358,15 @@ int replay_revisions(struct rev_info *revs,
 	struct commit *last_commit = NULL;
 	struct commit *commit;
 	struct commit *onto = NULL;
-	struct merge_options merge_opt;
+	struct merge_options merge_opt = { 0 };
 	struct merge_result result = {
 		.clean = 1,
 	};
 	bool detached_head;
 	char *advance;
 	char *revert;
+	const char *ref;
+	struct object_id old_oid;
 	enum replay_mode mode = REPLAY_MODE_PICK;
 	int ret;
 
@@ -375,6 +377,27 @@ int replay_revisions(struct rev_info *revs,
 	set_up_replay_mode(revs->repo, &revs->cmdline, opts->onto,
 			   &detached_head, &advance, &revert, &onto, &update_refs);
 
+	if (opts->ref) {
+		struct object_id oid;
+
+		if (update_refs && strset_get_size(update_refs) > 1) {
+			ret = error(_("'--ref' cannot be used with multiple revision ranges"));
+			goto out;
+		}
+		if (check_refname_format(opts->ref, 0) || !starts_with(opts->ref, "refs/")) {
+			ret = error(_("'%s' is not a valid refname"), opts->ref);
+			goto out;
+		}
+		ref = opts->ref;
+		if (!refs_read_ref(get_main_ref_store(revs->repo), opts->ref, &oid))
+			oidcpy(&old_oid, &oid);
+		else
+			oidclr(&old_oid, revs->repo->hash_algo);
+	} else {
+		ref = advance ? advance : revert;
+		oidcpy(&old_oid, &onto->object.oid);
+	}
+
 	if (prepare_revision_walk(revs) < 0) {
 		ret = error(_("error preparing revisions"));
 		goto out;
@@ -406,7 +429,7 @@ int replay_revisions(struct rev_info *revs,
 		kh_value(replayed_commits, pos) = last_commit;
 
 		/* Update any necessary branches */
-		if (advance || revert)
+		if (ref)
 			continue;
 
 		for (decoration = get_name_decoration(&commit->object);
@@ -440,13 +463,9 @@ int replay_revisions(struct rev_info *revs,
 		goto out;
 	}
 
-	/* In --advance or --revert mode, update the target ref */
-	if (advance || revert) {
-		const char *ref = advance ? advance : revert;
-		replay_result_queue_update(out, ref,
-					   &onto->object.oid,
+	if (ref)
+		replay_result_queue_update(out, ref, &old_oid,
 					   &last_commit->object.oid);
-	}
 
 	ret = 0;
 
diff --git a/replay.h b/replay.h
index e916a5f975..0ab74b9805 100644
--- a/replay.h
+++ b/replay.h
@@ -25,6 +25,13 @@ struct replay_revisions_options {
 	const char *onto;
 
 	/*
+	 * Reference to update with the result of the replay. This will not
+	 * update any refs from `onto`, `advance`, or `revert`. Ignores
+	 * `contained`.
+	 */
+	const char *ref;
+
+	/*
 	 * Starting point at which to create revert commits; must be a branch
 	 * name. The branch will be updated to point to the revert commits.
 	 * This option is mutually exclusive with `onto` and `advance`.
diff --git a/t/t3650-replay-basics.sh b/t/t3650-replay-basics.sh
index 89819ad4d2..3353bc4a4d 100755
--- a/t/t3650-replay-basics.sh
+++ b/t/t3650-replay-basics.sh
@@ -499,4 +499,70 @@ test_expect_success 'git replay --revert incompatible with --advance' '
 	test_grep "cannot be used together" error
 '
 
+test_expect_success 'using --onto with --ref' '
+	git branch test-ref-onto topic2 &&
+	test_when_finished "git branch -D test-ref-onto" &&
+
+	git replay --ref-action=print --onto=main --ref=refs/heads/test-ref-onto topic1..topic2 >result &&
+
+	test_line_count = 1 result &&
+	test_grep "^update refs/heads/test-ref-onto " result &&
+
+	git log --format=%s $(cut -f 3 -d " " result) >actual &&
+	test_write_lines E D M L B A >expect &&
+	test_cmp expect actual
+'
+
+test_expect_success 'using --advance with --ref' '
+	git branch test-ref-advance main &&
+	git branch test-ref-target main &&
+	test_when_finished "git branch -D test-ref-advance test-ref-target" &&
+
+	git replay --ref-action=print --advance=test-ref-advance --ref=refs/heads/test-ref-target topic1..topic2 >result &&
+
+	test_line_count = 1 result &&
+	test_grep "^update refs/heads/test-ref-target " result
+'
+
+test_expect_success 'using --revert with --ref' '
+	git branch test-ref-revert topic4 &&
+	git branch test-ref-revert-target topic4 &&
+	test_when_finished "git branch -D test-ref-revert test-ref-revert-target" &&
+
+	git replay --ref-action=print --revert=test-ref-revert --ref=refs/heads/test-ref-revert-target topic4~1..topic4 >result &&
+
+	test_line_count = 1 result &&
+	test_grep "^update refs/heads/test-ref-revert-target " result
+'
+
+test_expect_success '--ref is incompatible with --contained' '
+	test_must_fail git replay --onto=main --ref=refs/heads/main --contained topic1..topic2 2>err &&
+	test_grep "cannot be used together" err
+'
+
+test_expect_success '--ref with nonexistent fully-qualified ref' '
+	test_when_finished "git update-ref -d refs/heads/new-branch" &&
+
+	git replay --onto=main --ref=refs/heads/new-branch topic1..topic2 &&
+
+	git log --format=%s -2 new-branch >actual &&
+	test_write_lines E D >expect &&
+	test_cmp expect actual
+'
+
+test_expect_success '--ref must be a valid refname' '
+	test_must_fail git replay --onto=main --ref="refs/heads/bad..ref" topic1..topic2 2>err &&
+	test_grep "is not a valid refname" err
+'
+
+test_expect_success '--ref requires fully qualified ref' '
+	test_must_fail git replay --onto=main --ref=main topic1..topic2 2>err &&
+	test_grep "is not a valid refname" err
+'
+
+test_expect_success '--onto with --ref rejects multiple revision ranges' '
+	test_must_fail git replay --onto=main --ref=refs/heads/topic2 ^topic1 topic2 topic4 2>err &&
+	test_grep "cannot be used with multiple revision ranges" err
+'
+
 test_done