commit: use split_ident_line to compare author/committer

Instead of string-wise comparing the author/committer lines
with their timestamps truncated, we can use split_ident_line
and ident_cmp. These functions are more robust than our
ad-hoc parsing, though in practice it should not matter, as
we just generated these ident lines ourselves.

However, this will also allow us easy access to the
timestamp and tz fields in future patches.
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

builtin/commit.c

@@ -585,13 +585,11 @@ static void determine_author_info(struct strbuf *author_ident)
 	}
 }
 
-static char *cut_ident_timestamp_part(char *string)
+static void split_ident_or_die(struct ident_split *id, const struct strbuf *buf)
 {
-	char *ket = strrchr(string, '>');
-	if (!ket || ket[1] != ' ')
-		die(_("Malformed ident string: '%s'"), string);
-	*++ket = '\0';
-	return ket;
+	if (split_ident_line(id, buf->buf, buf->len) ||
+	    !sane_ident_split(id))
+		die(_("Malformed ident string: '%s'"), buf->buf);
 }
 
 static int prepare_to_commit(const char *index_file, const char *prefix,
@@ -755,7 +753,8 @@ static int prepare_to_commit(const char *index_file, const char *prefix,
 	if (use_editor && include_status) {
 		int ident_shown = 0;
 		int saved_color_setting;
-		char *ai_tmp, *ci_tmp;
+		struct ident_split ci, ai;
+
 		if (whence != FROM_COMMIT) {
 			if (cleanup_mode == CLEANUP_SCISSORS)
 				wt_status_add_cut_line(s->fp);
@@ -795,21 +794,24 @@ static int prepare_to_commit(const char *index_file, const char *prefix,
 			status_printf_ln(s, GIT_COLOR_NORMAL,
 					"%s", only_include_assumed);
 
-		ai_tmp = cut_ident_timestamp_part(author_ident->buf);
-		ci_tmp = cut_ident_timestamp_part(committer_ident.buf);
-		if (strcmp(author_ident->buf, committer_ident.buf))
+		split_ident_or_die(&ai, author_ident);
+		split_ident_or_die(&ci, &committer_ident);
+
+		if (ident_cmp(&ai, &ci))
 			status_printf_ln(s, GIT_COLOR_NORMAL,
 				_("%s"
-				"Author:    %s"),
+				"Author:    %.*s <%.*s>"),
 				ident_shown++ ? "" : "\n",
-				author_ident->buf);
+				(int)(ai.name_end - ai.name_begin), ai.name_begin,
+				(int)(ai.mail_end - ai.mail_begin), ai.mail_begin);
 
 		if (!committer_ident_sufficiently_given())
 			status_printf_ln(s, GIT_COLOR_NORMAL,
 				_("%s"
-				"Committer: %s"),
+				"Committer: %.*s <%.*s>"),
 				ident_shown++ ? "" : "\n",
-				committer_ident.buf);
+				(int)(ci.name_end - ci.name_begin), ci.name_begin,
+				(int)(ci.mail_end - ci.mail_begin), ci.mail_begin);
 
 		if (ident_shown)
 			status_printf_ln(s, GIT_COLOR_NORMAL, "");
@@ -818,9 +820,6 @@ static int prepare_to_commit(const char *index_file, const char *prefix,
 		s->use_color = 0;
 		commitable = run_status(s->fp, index_file, prefix, 1, s);
 		s->use_color = saved_color_setting;
-
-		*ai_tmp = ' ';
-		*ci_tmp = ' ';
 	} else {
 		unsigned char sha1[20];
 		const char *parent = "HEAD";