Re: [PATCH] commit: add --committer option

> Phillip Wood <phillip.wood123@gmail.com> 于2025年11月11日周二 00:50写道：
>> On 09/11/2025 10:22, ZheNing Hu via GitGitGadget wrote:
>>> From: ZheNing Hu <adlternative@gmail.com>
>>>
>>>
>>>       This patch introduces the --committer option to git-commit, providing:
>>>
>>>        1. Consistency with the existing --author option
>>>        2. A more convenient alternative to environment variables
>>>        3. Better support for automated workflows and scripts
>>>        4. Improved user experience when managing multiple identities
>>
>> What's the use case for the same person committing under different
>> identities? We already have a config mechanism to set different
>> identities for different repositories but I'm struggling to see why
>> someone would want to create commits under multiple identities in a
>> single repository. For scripts it easy enough to set the relevant
>> environment variables if a tool wants to create commits under its own
>> identity.
>>
> 
> I frequently need to distinguish between different user.name and user.email
> configurations on our company's internal GitHub.
> 
> The current problems are:
> 
> When I misconfigure (which happens occasionally), git commit --author only fixes
> the author part, I still need to additionally set GIT_COMMITTER_NAME and
> GIT_COMMITTER_EMAIL environment variables to fix the committer information
> These environment variables are painful to use, requiring manual setup
> every time

> If a --committer option could be provided to align with --author, users wouldn't
> need to remember and use these additional environment variables.
> This would greatly simplify the workflow and reduce cognitive overhead.
> 
> 
>> Thanks
>>
>> Phillip
>>
>>>       The implementation follows the same pattern as the --author option,
>>>       accepting the format "Name " and properly validating the input.
>>>
>>> Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-1997%2Fadlternative%2Fzh%2Fimplement-committer-option-v1
>>> Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-1997/adlternative/zh/implement-committer-option-v1
>>> Pull-Request: https://github.com/gitgitgadget/git/pull/1997
>>>
>>>    Documentation/git-commit.adoc |  9 +++-
>>>    builtin/commit.c              | 58 ++++++++++++++++++++++++-
>>>    t/t7509-commit-authorship.sh  | 80 +++++++++++++++++++++++++++++++++++
>>>    3 files changed, 144 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/Documentation/git-commit.adoc b/Documentation/git-commit.adoc
>>> index 54c207ad45..a015c8328e 100644
>>> --- a/Documentation/git-commit.adoc
>>> +++ b/Documentation/git-commit.adoc
>>> @@ -12,7 +12,7 @@ git commit [-a | --interactive | --patch] [-s] [-v] [-u[<mode>]] [--amend]
>>>           [--dry-run] [(-c | -C | --squash) <commit> | --fixup [(amend|reword):]<commit>]
>>>           [-F <file> | -m <msg>] [--reset-author] [--allow-empty]
>>>           [--allow-empty-message] [--no-verify] [-e] [--author=<author>]
>>> -        [--date=<date>] [--cleanup=<mode>] [--[no-]status]
>>> +        [--date=<date>] [--committer=<committer>] [--cleanup=<mode>] [--[no-]status]
>>>           [-i | -o] [--pathspec-from-file=<file> [--pathspec-file-nul]]
>>>           [(--trailer <token>[(=|:)<value>])...] [-S[<keyid>]]
>>>           [--] [<pathspec>...]
>>> @@ -181,6 +181,13 @@ See linkgit:git-rebase[1] for details.
>>>    `--date=<date>`::
>>>        Override the author date used in the commit.
>>>
>>> +`--committer=<committer>`::
>>> +     Override the committer for the commit. Specify an explicit committer using the
>>> +     standard `A U Thor <committer@example.com>` format. Otherwise _<committer>_
>>> +     is assumed to be a pattern and is used to search for an existing
>>> +     commit by that author (i.e. `git rev-list --all -i --author=<committer>`);
>>> +     the commit author is then copied from the first such commit found.
>>> +
>>>    `-m <msg>`::
>>>    `--message=<msg>`::
>>>        Use _<msg>_ as the commit message.
>>> diff --git a/builtin/commit.c b/builtin/commit.c
>>> index 0243f17d53..88e77cbaab 100644
>>> --- a/builtin/commit.c
>>> +++ b/builtin/commit.c
>>> @@ -49,7 +49,7 @@ static const char * const builtin_commit_usage[] = {
>>>           "           [--dry-run] [(-c | -C | --squash) <commit> | --fixup [(amend|reword):]<commit>]\n"
>>>           "           [-F <file> | -m <msg>] [--reset-author] [--allow-empty]\n"
>>>           "           [--allow-empty-message] [--no-verify] [-e] [--author=<author>]\n"
>>> -        "           [--date=<date>] [--cleanup=<mode>] [--[no-]status]\n"
>>> +        "           [--date=<date>] [--committer=<committer>] [--cleanup=<mode>] [--[no-]status]\n"
>>>           "           [-i | -o] [--pathspec-from-file=<file> [--pathspec-file-nul]]\n"
>>>           "           [(--trailer <token>[(=|:)<value>])...] [-S[<keyid>]]\n"
>>>           "           [--] [<pathspec>...]"),
>>> @@ -112,6 +112,7 @@ static enum {
>>>    } commit_style;
>>>
>>>    static const char *force_author;
>>> +static const char *force_committer;
>>>    static char *logfile;
>>>    static char *template_file;
>>>    /*
>>> @@ -690,6 +691,48 @@ static void determine_author_info(struct strbuf *author_ident)
>>>        free(date);
>>>    }
>>>
>>> +static void determine_committer_info(struct strbuf *committer_ident)
>>> +{
>>> +     char *name, *email, *date;
>>> +     struct ident_split committer;
>>> +
>>> +     name = xstrdup_or_null(getenv("GIT_COMMITTER_NAME"));
>>> +     email = xstrdup_or_null(getenv("GIT_COMMITTER_EMAIL"));
>>> +     date = xstrdup_or_null(getenv("GIT_COMMITTER_DATE"));
>>> +
>>> +     if (force_committer) {
>>> +             struct ident_split ident;
>>> +
>>> +             if (split_ident_line(&ident, force_committer, strlen(force_committer)) < 0)
>>> +                     die(_("malformed --committer parameter"));
>>> +             set_ident_var(&name, xmemdupz(ident.name_begin, ident.name_end - ident.name_begin));
>>> +             set_ident_var(&email, xmemdupz(ident.mail_begin, ident.mail_end - ident.mail_begin));
>>> +
>>> +             if (ident.date_begin) {
>>> +                     struct strbuf date_buf = STRBUF_INIT;
>>> +                     strbuf_addch(&date_buf, '@');
>>> +                     strbuf_add(&date_buf, ident.date_begin, ident.date_end - ident.date_begin);
>>> +                     strbuf_addch(&date_buf, ' ');
>>> +                     strbuf_add(&date_buf, ident.tz_begin, ident.tz_end - ident.tz_begin);
>>> +                     set_ident_var(&date, strbuf_detach(&date_buf, NULL));
>>> +             }
>>> +     }
>>> +
>>> +     if (force_date) {
>>> +             struct strbuf date_buf = STRBUF_INIT;
>>> +             if (parse_force_date(force_date, &date_buf))
>>> +                     die(_("invalid date format: %s"), force_date);
>>> +             set_ident_var(&date, strbuf_detach(&date_buf, NULL));
>>> +     }
>>> +
>>> +     strbuf_addstr(committer_ident, fmt_ident(name, email, WANT_COMMITTER_IDENT, date,
>>> +                             IDENT_STRICT));
>>> +     assert_split_ident(&committer, committer_ident);
>>> +     free(name);
>>> +     free(email);
>>> +     free(date);
>>> +}
>>> +
>>>    static int author_date_is_interesting(void)
>>>    {
>>>        return author_message || force_date;
>>> @@ -1321,6 +1364,9 @@ static int parse_and_validate_options(int argc, const char *argv[],
>>>        if (force_author && renew_authorship)
>>>                die(_("options '%s' and '%s' cannot be used together"), "--reset-author", "--author");
>>>
>>> +     if (force_committer && !strchr(force_committer, '>'))
>>> +             force_committer = find_author_by_nickname(force_committer);
>>> +
>>>        if (logfile || have_option_m || use_message)
>>>                use_editor = 0;
>>>
>>> @@ -1709,6 +1755,7 @@ int cmd_commit(int argc,
>>>                OPT_FILENAME('F', "file", &logfile, N_("read message from file")),
>>>                OPT_STRING(0, "author", &force_author, N_("author"), N_("override author for commit")),
>>>                OPT_STRING(0, "date", &force_date, N_("date"), N_("override date for commit")),
>>> +             OPT_STRING(0, "committer", &force_committer, N_("committer"), N_("override committer for commit")),
>>>                OPT_CALLBACK('m', "message", &message, N_("message"), N_("commit message"), opt_parse_m),
>>>                OPT_STRING('c', "reedit-message", &edit_message, N_("commit"), N_("reuse and edit message from specified commit")),
>>>                OPT_STRING('C', "reuse-message", &use_message, N_("commit"), N_("reuse message from specified commit")),
>>> @@ -1785,6 +1832,7 @@ int cmd_commit(int argc,
>>>
>>>        struct strbuf sb = STRBUF_INIT;
>>>        struct strbuf author_ident = STRBUF_INIT;
>>> +     struct strbuf committer_ident = STRBUF_INIT;
>>>        const char *index_file, *reflog_msg;
>>>        struct object_id oid;
>>>        struct commit_list *parents = NULL;
>>> @@ -1930,8 +1978,13 @@ int cmd_commit(int argc,
>>>                append_merge_tag_headers(parents, &tail);
>>>        }
>>>
>>> +     if (force_committer) {
>>> +             determine_committer_info(&committer_ident);
>>> +     }
>>> +
>>>        if (commit_tree_extended(sb.buf, sb.len, &the_repository->index->cache_tree->oid,
>>> -                              parents, &oid, author_ident.buf, NULL,
>>> +                              parents, &oid, author_ident.buf,
>>> +                              force_committer ? committer_ident.buf : NULL,
>>>                                 sign_commit, extra)) {
>>>                rollback_index_files();
>>>                die(_("failed to write commit object"));
>>> @@ -1980,6 +2033,7 @@ cleanup:
>>>        free_commit_extra_headers(extra);
>>>        free_commit_list(parents);
>>>        strbuf_release(&author_ident);
>>> +     strbuf_release(&committer_ident);
>>>        strbuf_release(&err);
>>>        strbuf_release(&sb);
>>>        free(logfile);
>>> diff --git a/t/t7509-commit-authorship.sh b/t/t7509-commit-authorship.sh
>>> index 8e373b566b..45527f6a70 100755
>>> --- a/t/t7509-commit-authorship.sh
>>> +++ b/t/t7509-commit-authorship.sh
>>> @@ -12,6 +12,11 @@ author_header () {
>>>        sed -n -e '/^$/q' -e '/^author /p'
>>>    }
>>>
>>> +committer_header () {
>>> +     git cat-file commit "$1" |
>>> +     sed -n -e '/^$/q' -e '/^committer /p'
>>> +}
>>> +
>>>    message_body () {
>>>        git cat-file commit "$1" |
>>>        sed -e '1,/^$/d'
>>> @@ -171,4 +176,79 @@ test_expect_success '--reset-author with CHERRY_PICK_HEAD' '
>>>        test_cmp expect actual
>>>    '
>>>
>>> +test_expect_success '--committer option overrides committer' '
>>> +     git checkout Initial &&
>>> +     echo "Test --committer" >>foo &&
>>> +     test_tick &&
>>> +     git commit -a -m "test committer" --committer="Custom Committer <custom@committer.example>" &&
>>> +     committer_header HEAD >actual &&
>>> +     grep "Custom Committer <custom@committer.example>" actual
>>> +'
>>> +
>>> +test_expect_success '--committer with pattern search' '
>>> +     echo "Test committer pattern" >>foo &&
>>> +     test_tick &&
>>> +     git commit -a -m "test committer pattern" --committer="Frigate" &&
>>> +     committer_header HEAD >actual &&
>>> +     grep "Frigate <flying@over.world>" actual
>>> +'
>>> +
>>> +test_expect_success '--committer malformed parameter' '
>>> +     echo "Test malformed" >>foo &&
>>> +     test_tick &&
>>> +     test_must_fail git commit -a -m "test malformed" --committer="malformed committer"
>>> +'
>>> +
>>> +test_expect_success '--committer with --amend option' '
>>> +     git checkout -f Initial &&
>>> +     echo "Test committer with amend" >>foo &&
>>> +     test_tick &&
>>> +     git commit -a -m "initial commit for amend test" &&
>>> +     echo "Modified for amend" >>foo &&
>>> +     test_tick &&
>>> +     git commit -a --amend --no-edit \
>>> +             --author="Test Author <test@author.example>" \
>>> +             --committer="Test Committer <test@committer.example>" &&
>>> +     author_header HEAD >actual_author &&
>>> +     grep "Test Author <test@author.example>" actual_author &&
>>> +     committer_header HEAD >actual_committer &&
>>> +     grep "Test Committer <test@committer.example>" actual_committer
>>> +'
>>> +
>>> +test_expect_success 'GIT_COMMITTER_* environment variables' '
>>> +     git checkout -f Initial &&
>>> +     echo "Test env vars" >>foo &&
>>> +     test_tick &&
>>> +     GIT_COMMITTER_NAME="Env Committer" \
>>> +     GIT_COMMITTER_EMAIL="env@test.example" \
>>> +     git commit -a -m "test committer env vars" &&
>>> +     committer_header HEAD >actual &&
>>> +     grep "Env Committer <env@test.example>" actual
>>> +'
>>> +
>>> +test_expect_success '--committer overrides GIT_COMMITTER_* environment variables' '
>>> +     echo "Test override" >>foo &&
>>> +     test_tick &&
>>> +     GIT_COMMITTER_NAME="Env Committer" \
>>> +     GIT_COMMITTER_EMAIL="env@test.example" \
>>> +     git commit -a -m "test override" \
>>> +             --committer="Override Committer <override@test.example>" &&
>>> +     committer_header HEAD >actual &&
>>> +     grep "Override Committer <override@test.example>" actual
>>> +'
>>> +
>>> +test_expect_success '--date with --committer changes both author and committer dates' '
>>> +     git checkout -f Initial &&
>>> +     echo "Test date override" >>foo &&
>>> +     test_tick &&
>>> +     git commit -a -m "test date" \
>>> +             --author="Date Author <date@author.example>" \
>>> +             --committer="Date Committer <date@committer.example>" \
>>> +             --date="2024-06-15 10:30:00 +0800" &&
>>> +     git log -1 --format="%ai" >author_date &&
>>> +     git log -1 --format="%ci" >committer_date &&
>>> +     grep "2024-06-15 10:30:00 +0800" author_date &&
>>> +     grep "2024-06-15 10:30:00 +0800" committer_date
>>> +'
>>> +
>>>    test_done
>>>
>>> base-commit: 4badef0c3503dc29059d678abba7fac0f042bc84
>>
>