SYNOPSIS
--------
[verse]
-(EXPERIMENTAL!) 'git replay' ([--contained] --onto <newbase> | --advance <branch>) <revision-range>...
+(EXPERIMENTAL!) 'git replay' ([--contained] --onto <newbase> | --advance <branch>) [--output-commands | --allow-partial] <revision-range>...
DESCRIPTION
-----------
Takes ranges of commits and replays them onto a new location. Leaves
-the working tree and the index untouched, and updates no references.
-The output of this command is meant to be used as input to
-`git update-ref --stdin`, which would update the relevant branches
-(see the OUTPUT section below).
+the working tree and the index untouched, and by default updates the
+relevant references using atomic transactions. Use `--output-commands`
+to get the old default behavior where update commands that can be piped
+to `git update-ref --stdin` are emitted (see the OUTPUT section below).
THIS COMMAND IS EXPERIMENTAL. THE BEHAVIOR MAY CHANGE.
will update the branch passed as an argument to `--advance` to point at
the new commits (in other words, this mimics a cherry-pick operation).
+--output-commands::
+ Output update-ref commands instead of updating refs directly.
+ When this option is used, the output can be piped to `git update-ref --stdin`
+ for successive, relatively slow, ref updates. This is equivalent to the
+ old default behavior.
+
+--allow-partial::
+ Allow some ref updates to succeed even if others fail. By default,
+ ref updates are atomic (all succeed or all fail). With this option,
+ failed updates are reported as warnings rather than causing the entire
+ command to fail. The command exits with code 0 only if all updates
+ succeed; any failures result in exit code 1. Cannot be used with
+ `--output-commands`.
+
<revision-range>::
Range of commits to replay. More than one <revision-range> can
be passed, but in `--advance <branch>` mode, they should have
OUTPUT
------
-When there are no conflicts, the output of this command is usable as
-input to `git update-ref --stdin`. It is of the form:
+By default, when there are no conflicts, this command updates the relevant
+references using atomic transactions and produces no output. All ref updates
+succeed or all fail (atomic behavior). Use `--allow-partial` to allow some
+updates to succeed while others fail.
+
+When `--output-commands` is used, the output is usable as input to
+`git update-ref --stdin`. It is of the form:
update refs/heads/branch1 ${NEW_branch1_HASH} ${OLD_branch1_HASH}
update refs/heads/branch2 ${NEW_branch2_HASH} ${OLD_branch2_HASH}
update refs/heads/branch3 ${NEW_branch3_HASH} ${OLD_branch3_HASH}
where the number of refs updated depends on the arguments passed and
-the shape of the history being replayed. When using `--advance`, the
+the shape of the history being replayed. When using `--advance`, the
number of refs updated is always one, but for `--onto`, it can be one
or more (rebasing multiple branches simultaneously is supported).
EXAMPLES
--------
-To simply rebase `mybranch` onto `target`:
+To simply rebase `mybranch` onto `target` (default behavior):
------------
$ git replay --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
-update refs/heads/target ${NEW_target_HASH} ${OLD_target_HASH}
------------
Note that the first two examples replay the exact same commits and on
top of the exact same new base, they only differ in that the first
-provides instructions to make mybranch point at the new commits and
-the second provides instructions to make target point at them.
+updates mybranch to point at the new commits and the second updates
+target to point at them.
+
+To get the old default behavior where update commands are emitted:
+
+------------
+$ git replay --output-commands --onto target origin/main..mybranch
+update refs/heads/mybranch ${NEW_mybranch_HASH} ${OLD_mybranch_HASH}
+------------
+
+To rebase multiple branches with partial failure tolerance:
+
+------------
+$ git replay --allow-partial --contained --onto origin/main origin/main..tipbranch
+------------
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
+------------
+
+This automatically finds and rebases all branches contained within the
+`origin/main..tipbranch` range.
+
+Or if you want to see the old default behavior where update commands are emitted:
+
+------------
+$ git replay --output-commands --contained --onto origin/main origin/main..tipbranch
update refs/heads/branch1 ${NEW_branch1_HASH} ${OLD_branch1_HASH}
update refs/heads/branch2 ${NEW_branch2_HASH} ${OLD_branch2_HASH}
update refs/heads/tipbranch ${NEW_tipbranch_HASH} ${OLD_tipbranch_HASH}
When calling `git replay`, one does not need to specify a range of
commits to replay using the syntax `A..B`; any range expression will
-do:
+do. Here's an example where you explicitly specify which branches to rebase:
------------
$ git replay --onto origin/main ^base branch1 branch2 branch3
+------------
+
+This gives you explicit control over exactly which branches are rebased,
+unlike the previous `--contained` example which automatically discovers them.
+
+To see the update commands that would be executed:
+
+------------
+$ git replay --output-commands --onto origin/main ^base branch1 branch2 branch3
update refs/heads/branch1 ${NEW_branch1_HASH} ${OLD_branch1_HASH}
update refs/heads/branch2 ${NEW_branch2_HASH} ${OLD_branch2_HASH}
update refs/heads/branch3 ${NEW_branch3_HASH} ${OLD_branch3_HASH}
return create_commit(repo, result->tree, pickme, replayed_base);
}
+static int add_ref_to_transaction(struct ref_transaction *transaction,
+ const char *refname,
+ const struct object_id *new_oid,
+ const struct object_id *old_oid,
+ struct strbuf *err)
+{
+ return ref_transaction_update(transaction, refname, new_oid, old_oid,
+ NULL, NULL, 0, "git replay", err);
+}
+
+static void print_rejected_update(const char *refname,
+ const struct object_id *old_oid UNUSED,
+ const struct object_id *new_oid UNUSED,
+ const char *old_target UNUSED,
+ const char *new_target UNUSED,
+ enum ref_transaction_error err,
+ void *cb_data UNUSED)
+{
+ const char *reason = ref_transaction_error_msg(err);
+ warning(_("failed to update %s: %s"), refname, reason);
+}
+
int cmd_replay(int argc,
const char **argv,
const char *prefix,
struct commit *onto = NULL;
const char *onto_name = NULL;
int contained = 0;
+ int output_commands = 0;
+ int allow_partial = 0;
struct rev_info revs;
struct commit *last_commit = NULL;
struct merge_result result;
struct strset *update_refs = NULL;
kh_oid_map_t *replayed_commits;
+ struct ref_transaction *transaction = NULL;
+ struct strbuf transaction_err = STRBUF_INIT;
+ int commits_processed = 0;
int ret = 0;
- const char * const replay_usage[] = {
+ const char *const replay_usage[] = {
N_("(EXPERIMENTAL!) git replay "
"([--contained] --onto <newbase> | --advance <branch>) "
- "<revision-range>..."),
+ "[--output-commands | --allow-partial] <revision-range>..."),
NULL
};
struct option replay_options[] = {
N_("replay onto given commit")),
OPT_BOOL(0, "contained", &contained,
N_("advance all branches contained in revision-range")),
+ OPT_BOOL(0, "output-commands", &output_commands,
+ N_("output update commands instead of updating refs")),
+ OPT_BOOL(0, "allow-partial", &allow_partial,
+ N_("allow some ref updates to succeed even if others fail")),
OPT_END()
};
usage_with_options(replay_usage, replay_options);
}
- if (advance_name_opt && contained)
- die(_("options '%s' and '%s' cannot be used together"),
- "--advance", "--contained");
+ die_for_incompatible_opt2(!!advance_name_opt, "--advance",
+ contained, "--contained");
+
+ die_for_incompatible_opt2(allow_partial, "--allow-partial",
+ output_commands, "--output-commands");
+
advance_name = xstrdup_or_null(advance_name_opt);
repo_init_revisions(repo, &revs, prefix);
determine_replay_mode(repo, &revs.cmdline, onto_name, &advance_name,
&onto, &update_refs);
+ if (!output_commands) {
+ unsigned int transaction_flags = allow_partial ? REF_TRANSACTION_ALLOW_FAILURE : 0;
+ transaction = ref_store_transaction_begin(get_main_ref_store(repo),
+ transaction_flags,
+ &transaction_err);
+ if (!transaction) {
+ ret = error(_("failed to begin ref transaction: %s"), transaction_err.buf);
+ goto cleanup;
+ }
+ }
+
if (!onto) /* FIXME: Should handle replaying down to root commit */
die("Replaying down to root commit is not supported yet!");
khint_t pos;
int hr;
+ commits_processed = 1;
+
if (!commit->parents)
die(_("replaying down to root commit is not supported yet!"));
if (commit->parents->next)
if (decoration->type == DECORATION_REF_LOCAL &&
(contained || strset_contains(update_refs,
decoration->name))) {
- printf("update %s %s %s\n",
- decoration->name,
- oid_to_hex(&last_commit->object.oid),
- oid_to_hex(&commit->object.oid));
+ if (output_commands) {
+ printf("update %s %s %s\n",
+ decoration->name,
+ oid_to_hex(&last_commit->object.oid),
+ oid_to_hex(&commit->object.oid));
+ } else if (add_ref_to_transaction(transaction, decoration->name,
+ &last_commit->object.oid,
+ &commit->object.oid,
+ &transaction_err) < 0) {
+ ret = error(_("failed to add ref update to transaction: %s"), transaction_err.buf);
+ goto cleanup;
+ }
}
decoration = decoration->next;
}
/* In --advance mode, advance the target ref */
if (result.clean == 1 && advance_name) {
- printf("update %s %s %s\n",
- advance_name,
- oid_to_hex(&last_commit->object.oid),
- oid_to_hex(&onto->object.oid));
+ if (output_commands) {
+ printf("update %s %s %s\n",
+ advance_name,
+ oid_to_hex(&last_commit->object.oid),
+ oid_to_hex(&onto->object.oid));
+ } else if (add_ref_to_transaction(transaction, advance_name,
+ &last_commit->object.oid,
+ &onto->object.oid,
+ &transaction_err) < 0) {
+ ret = error(_("failed to add ref update to transaction: %s"), transaction_err.buf);
+ goto cleanup;
+ }
+ }
+
+ /* Commit the ref transaction if we have one */
+ if (transaction && result.clean == 1) {
+ if (ref_transaction_commit(transaction, &transaction_err)) {
+ if (allow_partial) {
+ warning(_("some ref updates failed: %s"), transaction_err.buf);
+ ref_transaction_for_each_rejected_update(transaction,
+ print_rejected_update, NULL);
+ ret = 0; /* Set failure even with allow_partial */
+ } else {
+ ret = error(_("failed to update refs: %s"), transaction_err.buf);
+ goto cleanup;
+ }
+ }
}
merge_finalize(&merge_opt, &result);
strset_clear(update_refs);
free(update_refs);
}
- ret = result.clean;
+
+ /* Handle empty ranges: if no commits were processed, treat as success */
+ if (!commits_processed)
+ ret = 1; /* Success - no commits to replay is not an error */
+ else
+ ret = result.clean;
cleanup:
+ if (transaction)
+ ref_transaction_free(transaction);
+ strbuf_release(&transaction_err);
release_revisions(&revs);
free(advance_name);
'
test_expect_success 'using replay to rebase two branches, one on top of other' '
- git replay --onto main topic1..topic2 >result &&
+ git replay --output-commands --onto main topic1..topic2 >result &&
test_line_count = 1 result &&
test_cmp expect result
'
+test_expect_success 'using replay with default atomic behavior (no output)' '
+ # Create a test branch that wont interfere with others
+ git branch atomic-test topic2 &&
+ git rev-parse atomic-test >atomic-test-old &&
+
+ # Default behavior: atomic ref updates (no output)
+ git replay --onto main topic1..atomic-test >output &&
+ test_must_be_empty output &&
+
+ # Verify the branch was updated
+ git rev-parse atomic-test >atomic-test-new &&
+ ! test_cmp atomic-test-old atomic-test-new &&
+
+ # Verify the history is correct
+ git log --format=%s atomic-test >actual &&
+ test_write_lines E D M L B A >expect &&
+ test_cmp expect actual
+'
+
test_expect_success 'using replay on bare repo to rebase two branches, one on top of other' '
- git -C bare replay --onto main topic1..topic2 >result-bare &&
- test_cmp expect result-bare
+ git -C bare replay --output-commands --onto main topic1..topic2 >result-bare &&
+
+ # The result should match what we got from the regular repo
+ test_cmp result result-bare
'
test_expect_success 'using replay to rebase with a conflict' '
# 2nd field of result is refs/heads/main vs. refs/heads/topic2
# 4th field of result is hash for main instead of hash for topic2
- git replay --advance main topic1..topic2 >result &&
+ git replay --output-commands --advance main topic1..topic2 >result &&
test_line_count = 1 result &&
'
test_expect_success 'using replay on bare repo to perform basic cherry-pick' '
- git -C bare replay --advance main topic1..topic2 >result-bare &&
+ git -C bare replay --output-commands --advance main topic1..topic2 >result-bare &&
test_cmp expect result-bare
'
'
test_expect_success 'using replay to also rebase a contained branch' '
- git replay --contained --onto main main..topic3 >result &&
+ git replay --output-commands --contained --onto main main..topic3 >result &&
test_line_count = 2 result &&
cut -f 3 -d " " result >new-branch-tips &&
'
test_expect_success 'using replay on bare repo to also rebase a contained branch' '
- git -C bare replay --contained --onto main main..topic3 >result-bare &&
+ git -C bare replay --output-commands --contained --onto main main..topic3 >result-bare &&
test_cmp expect result-bare
'
test_expect_success 'using replay to rebase multiple divergent branches' '
- git replay --onto main ^topic1 topic2 topic4 >result &&
+ git replay --output-commands --onto main ^topic1 topic2 topic4 >result &&
test_line_count = 2 result &&
cut -f 3 -d " " result >new-branch-tips &&
'
test_expect_success 'using replay on bare repo to rebase multiple divergent branches, including contained ones' '
- git -C bare replay --contained --onto main ^main topic2 topic3 topic4 >result &&
+ git -C bare replay --output-commands --contained --onto main ^main topic2 topic3 topic4 >result &&
test_line_count = 4 result &&
cut -f 3 -d " " result >new-branch-tips &&
--onto rename-onto rename-onto..rename-from
'
+# Tests for new default atomic behavior and options
+
+test_expect_success 'replay default behavior should not produce output when successful' '
+ git replay --onto main topic1..topic3 >output &&
+ test_must_be_empty output
+'
+
+test_expect_success 'replay with --output-commands produces traditional output' '
+ git replay --output-commands --onto main topic1..topic3 >output &&
+ test_line_count = 1 output &&
+ grep "^update refs/heads/topic3 " output
+'
+
+test_expect_success 'replay with --allow-partial should not produce output when successful' '
+ git replay --allow-partial --onto main topic1..topic3 >output &&
+ test_must_be_empty output
+'
+
+test_expect_success 'replay fails when --output-commands and --allow-partial are used together' '
+ test_must_fail git replay --output-commands --allow-partial --onto main topic1..topic2 2>error &&
+ grep "cannot be used together" error
+'
+
+test_expect_success 'replay with --contained updates multiple branches atomically' '
+ # Create fresh test branches based on the original structure
+ # contained-topic1 should be contained within the range to contained-topic3
+ git branch contained-base main &&
+ git checkout -b contained-topic1 contained-base &&
+ test_commit ContainedC &&
+ git checkout -b contained-topic3 contained-topic1 &&
+ test_commit ContainedG &&
+ test_commit ContainedH &&
+ git checkout main &&
+
+ # Store original states
+ git rev-parse contained-topic1 >contained-topic1-old &&
+ git rev-parse contained-topic3 >contained-topic3-old &&
+
+ # Use --contained to update multiple branches - this should update both
+ git replay --contained --onto main contained-base..contained-topic3 &&
+
+ # Verify both branches were updated
+ git rev-parse contained-topic1 >contained-topic1-new &&
+ git rev-parse contained-topic3 >contained-topic3-new &&
+ ! test_cmp contained-topic1-old contained-topic1-new &&
+ ! test_cmp contained-topic3-old contained-topic3-new
+'
+
+test_expect_success 'replay atomic behavior: all refs updated or none' '
+ # Store original state
+ git rev-parse topic4 >topic4-old &&
+
+ # Default atomic behavior
+ git replay --onto main main..topic4 &&
+
+ # Verify ref was updated
+ git rev-parse topic4 >topic4-new &&
+ ! test_cmp topic4-old topic4-new &&
+
+ # Verify no partial state
+ git log --format=%s topic4 >actual &&
+ test_write_lines J I M L B A >expect &&
+ test_cmp expect actual
+'
+
+test_expect_success 'replay works correctly with bare repositories' '
+ # Test atomic behavior in bare repo (important for Gitaly)
+ git checkout -b bare-test topic1 &&
+ test_commit BareTest &&
+
+ # Test with bare repo - replay the commits from main..bare-test to get the full history
+ git -C bare fetch .. bare-test:bare-test &&
+ git -C bare replay --onto main main..bare-test &&
+
+ # Verify the bare repo was updated correctly (no output)
+ git -C bare log --format=%s bare-test >actual &&
+ test_write_lines BareTest F C M L B A >expect &&
+ test_cmp expect actual
+'
+
+test_expect_success 'replay --allow-partial with no failures produces no output' '
+ git checkout -b partial-test topic1 &&
+ test_commit PartialTest &&
+
+ # Should succeed silently even with partial mode
+ git replay --allow-partial --onto main topic1..partial-test >output &&
+ test_must_be_empty output
+'
+
+test_expect_success 'replay maintains ref update consistency' '
+ # Test that traditional vs atomic produce equivalent results
+ git checkout -b method1-test topic2 &&
+ git checkout -b method2-test topic2 &&
+
+ # Both methods should update refs to point to the same replayed commits
+ git replay --output-commands --onto main topic1..method1-test >update-commands &&
+ git update-ref --stdin <update-commands &&
+ git log --format=%s method1-test >traditional-result &&
+
+ # Direct atomic method should produce same commit history
+ git replay --onto main topic1..method2-test &&
+ git log --format=%s method2-test >atomic-result &&
+
+ # Both methods should produce identical commit histories
+ test_cmp traditional-result atomic-result
+'
+
+test_expect_success 'replay error messages are helpful and clear' '
+ # Test that error messages are clear
+ test_must_fail git replay --output-commands --allow-partial --onto main topic1..topic2 2>error &&
+ grep "cannot be used together" error
+'
+
+test_expect_success 'replay with empty range produces no output and no changes' '
+ # Create a test branch for empty range testing
+ git checkout -b empty-test topic1 &&
+ git rev-parse empty-test >empty-test-before &&
+
+ # Empty range should succeed but do nothing
+ git replay --onto main empty-test..empty-test >output &&
+ test_must_be_empty output &&
+
+ # Branch should be unchanged
+ git rev-parse empty-test >empty-test-after &&
+ test_cmp empty-test-before empty-test-after
+'
+
test_done
projects / thirdparty / git.git / commitdiff
