Subject: Re: [PATCH] git-commit: search author pattern against mailmap

From: Junio C Hamano <[email-masked]>
Date: Fri, 23 Aug 2013 10:44:03 -0700

Antoine Pelisse <[email-masked]> writes:

> When committing for someone else, using the --author option, it can be
> nice to use the mailmap file to find the correct name spelling and email
> address.
>
> Currently, you would have to find the correct mapping in mailmap file
> first, and then use the full ident form when committing.
>
> Let's allow git-commit to find if an entry exists in mailmap file for
> that pattern, and use that instead.
>
> Signed-off-by: Antoine Pelisse <[email-masked]>
> ---
> Hi,
> I would use that feature at work where I happen to commit some work for
> other colleagues, while we heavily rely on mailmap file to have decent indents.
>
> On the other hand, I'm kind of embarrassed to add this new option to
> git-commit.

My initial reaction was "Why should something as important as 'git
commit' should be playing a guessing-game?" ;-) and I am kind of
ashamed to have added 146ea068 (git commit --author=$name: look
$name up in existing commits, 2008-08-26) and then am embarrased to
have completely forgotten about it. I never use the feature myself.

But for that old and established "--author parameter that does not
use the standard format guesses" feature to be useful, I agree that
it should honor the mailmap.

I wonder if it would hurt anybody if we made this unconditional, not
even with "--no-mailmap" override? Opinions?

>
>  Documentation/git-commit.txt |  6 +++++-
>  builtin/commit.c             | 16 +++++++++++++++-
>  2 files changed, 20 insertions(+), 2 deletions(-)
>
> diff --git a/Documentation/git-commit.txt b/Documentation/git-commit.txt
> index 1a7616c..9e3fe04 100644
> --- a/Documentation/git-commit.txt
> +++ b/Documentation/git-commit.txt
> @@ -12,7 +12,7 @@ SYNOPSIS
>  	   [--dry-run] [(-c | -C | --fixup | --squash) <commit>]
>  	   [-F <file> | -m <msg>] [--reset-author] [--allow-empty]
>  	   [--allow-empty-message] [--no-verify] [-e] [--author=<author>]
> -	   [--date=<date>] [--cleanup=<mode>] [--[no-]status]
> +	   [--use-mailmap] [--date=<date>] [--cleanup=<mode>] [--[no-]status]
>  	   [-i | -o] [-S[<keyid>]] [--] [<file>...]
>
>  DESCRIPTION
> @@ -131,6 +131,10 @@ OPTIONS
>  	commit by that author (i.e. rev-list --all -i --author=<author>);
>  	the commit author is then copied from the first such commit found.
>
> +--use-mailmap::
> +	When used with `--author=<author>`, match the <author> pattern
> +	against mapped name and email. See linkgit:git-shortlog[1].
> +
>  --date=<date>::
>  	Override the author date used in the commit.
>
> diff --git a/builtin/commit.c b/builtin/commit.c
> index 10acc53..fbd0664 100644
> --- a/builtin/commit.c
> +++ b/builtin/commit.c
> @@ -30,6 +30,7 @@
>  #include "column.h"
>  #include "sequencer.h"
>  #include "notes-utils.h"
> +#include "mailmap.h"
>
>  static const char * const builtin_commit_usage[] = {
>  	N_("git commit [options] [--] <pathspec>..."),
> @@ -87,6 +88,7 @@ static enum {
>  } commit_style;
>
>  static const char *logfile, *force_author;
> +static int mailmap;
>  static const char *template_file;
>  /*
>   * The _message variables are commit names from which to take
> @@ -945,13 +947,24 @@ static const char *find_author_by_nickname(const char *name)
>  	av[++ac] = buf.buf;
>  	av[++ac] = NULL;
>  	setup_revisions(ac, av, &revs, NULL);
> +	if (mailmap) {
> +		revs.mailmap = xcalloc(1, sizeof(struct string_list));
> +		read_mailmap(revs.mailmap, NULL);
> +	}
>  	prepare_revision_walk(&revs);
>  	commit = get_revision(&revs);
>  	if (commit) {
>  		struct pretty_print_context ctx = {0};
> +		const char *format;
> +
> +		if (mailmap)
> +			format = "%aN <%aE>";
> +		else
> +			format = "%an <%ae>";
> +
>  		ctx.date_mode = DATE_NORMAL;
>  		strbuf_release(&buf);
> -		format_commit_message(commit, "%an <%ae>", &buf, &ctx);
> +		format_commit_message(commit, format, &buf, &ctx);
>  		return strbuf_detach(&buf, NULL);
>  	}
>  	die(_("No existing author found with '%s'"), name);
> @@ -1428,6 +1441,7 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
>  		OPT_GROUP(N_("Commit message options")),
>  		OPT_FILENAME('F', "file", &logfile, N_("read message from file")),
>  		OPT_STRING(0, "author", &force_author, N_("author"), N_("override author for commit")),
> +		OPT_BOOLEAN(0, "use-mailmap", &mailmap, N_("Use mailmap file when searching for author")),
>  		OPT_STRING(0, "date", &force_date, N_("date"), N_("override date 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")),
> --
> 1.8.4.rc4.1.g0d8beaa.dirty