From: Adrian Ratiu Date: Fri, 10 Apr 2026 09:06:00 +0000 (+0300) Subject: hook: allow pre-push parallel execution X-Git-Url: http://git.ipfire.org/gitweb/?a=commitdiff_plain;h=f776b77f0032fb342d567156626ef3fe9586443f;p=thirdparty%2Fgit.git hook: allow pre-push parallel execution pre-push is the only hook that keeps stdout and stderr separate (for backwards compatibility with git-lfs and potentially other users). This prevents parallelizing it because run-command needs stdout_to_stderr=1 to buffer and de-interleave parallel outputs. Since we now default to jobs=1, backwards compatibility is maintained without needing any extension or extra config: when no parallelism is requested, pre-push behaves exactly as before. When the user explicitly opts into parallelism via hook.jobs > 1, hook..jobs > 1, or -jN, they accept the changed output behavior. Document this and let get_hook_jobs() set stdout_to_stderr=1 automatically when jobs > 1, removing the need for any extension infrastructure. Signed-off-by: Adrian Ratiu Signed-off-by: Junio C Hamano --- diff --git a/Documentation/config/hook.adoc b/Documentation/config/hook.adoc index 21800db648..94c7a9808e 100644 --- a/Documentation/config/hook.adoc +++ b/Documentation/config/hook.adoc @@ -39,3 +39,7 @@ hook.jobs:: + This setting has no effect unless all configured hooks for the event have `hook..parallel` set to `true`. ++ +For `pre-push` hooks, which normally keep stdout and stderr separate, +setting this to a value greater than 1 (or passing `-j`) will merge stdout +into stderr to allow correct de-interleaving of parallel output. diff --git a/hook.c b/hook.c index 85c0de5e47..25762b6c8d 100644 --- a/hook.c +++ b/hook.c @@ -555,18 +555,24 @@ static void run_hooks_opt_clear(struct run_hooks_opt *options) strvec_clear(&options->args); } +/* + * When running in parallel, stdout must be merged into stderr so + * run-command can buffer and de-interleave outputs correctly. This + * applies even to hooks like pre-push that normally keep stdout and + * stderr separate: the user has opted into parallelism, so the output + * stream behavior changes accordingly. + */ +static void merge_output_if_parallel(struct run_hooks_opt *options) +{ + if (options->jobs > 1) + options->stdout_to_stderr = 1; +} + /* Determine how many jobs to use for hook execution. */ static unsigned int get_hook_jobs(struct repository *r, struct run_hooks_opt *options, struct string_list *hook_list) { - /* - * Hooks needing separate output streams must run sequentially. - * Next commit will allow parallelizing these as well. - */ - if (!options->stdout_to_stderr) - return 1; - /* * An explicit job count overrides everything else: this covers both * FORCE_SERIAL callers (for hooks that must never run in parallel) @@ -575,7 +581,7 @@ static unsigned int get_hook_jobs(struct repository *r, * aggressively than the default. */ if (options->jobs) - return options->jobs; + goto cleanup; /* * Use hook.jobs from the already-parsed config cache (in-repo), or @@ -603,6 +609,8 @@ static unsigned int get_hook_jobs(struct repository *r, } } +cleanup: + merge_output_if_parallel(options); return options->jobs; } diff --git a/hook.h b/hook.h index ba7056f872..01db4226a6 100644 --- a/hook.h +++ b/hook.h @@ -106,8 +106,10 @@ struct run_hooks_opt { * Send the hook's stdout to stderr. * * This is the default behavior for all hooks except pre-push, - * which has separate stdout and stderr streams for backwards - * compatibility reasons. + * which keeps stdout and stderr separate for backwards compatibility. + * When parallel execution is requested (jobs > 1), get_hook_jobs() + * overrides this to 1 for all hooks so run-command can de-interleave + * their outputs correctly. */ unsigned int stdout_to_stderr:1; diff --git a/t/t1800-hook.sh b/t/t1800-hook.sh index a3011a01ca..4a978aff5e 100755 --- a/t/t1800-hook.sh +++ b/t/t1800-hook.sh @@ -800,4 +800,36 @@ test_expect_success 'one non-parallel hook forces the whole event to run seriall test_cmp expect hook.order ' +test_expect_success 'client hooks: pre-push parallel execution merges stdout to stderr' ' + test_when_finished "rm -rf remote-par stdout.actual stderr.actual" && + git init --bare remote-par && + git remote add origin-par remote-par && + test_commit par-commit && + mkdir -p .git/hooks && + setup_hooks pre-push && + test_config hook.jobs 2 && + git push origin-par HEAD:main >stdout.actual 2>stderr.actual && + check_stdout_merged_to_stderr pre-push +' + +test_expect_success 'client hooks: pre-push runs in parallel when hook.jobs > 1' ' + test_when_finished "rm -rf repo-parallel remote-parallel" && + git init --bare remote-parallel && + git init repo-parallel && + git -C repo-parallel remote add origin ../remote-parallel && + test_commit -C repo-parallel A && + + write_sentinel_hook repo-parallel/.git/hooks/pre-push && + git -C repo-parallel config hook.hook-2.event pre-push && + git -C repo-parallel config hook.hook-2.command \ + "$(sentinel_detector sentinel hook.order)" && + git -C repo-parallel config hook.hook-2.parallel true && + + git -C repo-parallel config hook.jobs 2 && + + git -C repo-parallel push origin HEAD >out 2>err && + echo parallel >expect && + test_cmp expect repo-parallel/hook.order +' + test_done diff --git a/transport.c b/transport.c index e53936d87b..9406ec4f2d 100644 --- a/transport.c +++ b/transport.c @@ -1391,8 +1391,10 @@ static int run_pre_push_hook(struct transport *transport, opt.feed_pipe_cb_data_free = pre_push_hook_data_free; /* - * pre-push hooks expect stdout & stderr to be separate, so don't merge - * them to keep backwards compatibility with existing hooks. + * pre-push hooks keep stdout and stderr separate by default for + * backwards compatibility. When the user opts into parallel execution + * via hook.jobs > 1 or -j, get_hook_jobs() will set stdout_to_stderr=1 + * automatically so run-command can de-interleave the outputs. */ opt.stdout_to_stderr = 0;