Compact commit template message

We recently let the user know explicitly that an empty
commit message will abort the commit. However, this adds yet
another line to the template; let's rephrase and re-wrap so
that this fits back on two lines.

This patch also makes the "fatal: empty commit message?"
warning a bit less scary, since this is now a "feature"
instead of an error. However, we retain the non-zero exit
status to indicate to callers that nothing was committed.
Signed-off-by: NJeff King <peff@peff.net>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

builtin-commit.c

@@ -554,14 +554,18 @@ static int prepare_to_commit(const char *index_file, const char *prefix)
 
 		fprintf(fp,
 			"\n"
-			"# Please enter the commit message for your changes.\n"
-			"# To abort the commit, use an empty commit message.\n"
-			"# (Comment lines starting with '#' will ");
+			"# Please enter the commit message for your changes.");
 		if (cleanup_mode == CLEANUP_ALL)
-			fprintf(fp, "not be included)\n");
+			fprintf(fp,
+				" Lines starting\n"
+				"# with '#' will be ignored, and an empty"
+				" message aborts the commit.\n");
 		else /* CLEANUP_SPACE, that is. */
-			fprintf(fp, "be kept.\n"
-				"# You can remove them yourself if you want to)\n");
+			fprintf(fp,
+				" Lines starting\n"
+				"# with '#' will be kept; you may remove them"
+				" yourself if you want to.\n"
+				"# An empty message aborts the commit.\n");
 		if (only_include_assumed)
 			fprintf(fp, "# %s\n", only_include_assumed);
 
@@ -1004,7 +1008,8 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
 		stripspace(&sb, cleanup_mode == CLEANUP_ALL);
 	if (sb.len < header_len || message_is_empty(&sb, header_len)) {
 		rollback_index_files();
-		die("no commit message?  aborting commit.");
+		fprintf(stderr, "Aborting commit due to empty commit message.\n");
+		exit(1);
 	}
 	strbuf_addch(&sb, '\0');
 	if (is_encoding_utf8(git_commit_encoding) && !is_utf8(sb.buf))

t/t7502-commit.sh

@@ -141,16 +141,15 @@ test_expect_success 'cleanup commit messages (strip,-F)' '
 
 echo "sample
 
-# Please enter the commit message for your changes.
-# To abort the commit, use an empty commit message.
-# (Comment lines starting with '#' will not be included)" >expect
+# Please enter the commit message for your changes. Lines starting
+# with '#' will be ignored, and an empty message aborts the commit." >expect
 
 test_expect_success 'cleanup commit messages (strip,-F,-e)' '
 
 	echo >>negative &&
 	{ echo;echo sample;echo; } >text &&
 	git commit -e -F text -a &&
-	head -n 5 .git/COMMIT_EDITMSG >actual &&
+	head -n 4 .git/COMMIT_EDITMSG >actual &&
 	test_cmp expect actual
 
 '
@@ -163,7 +162,7 @@ test_expect_success 'author different from committer' '
 
 	echo >>negative &&
 	git commit -e -m "sample"
-	head -n 8 .git/COMMIT_EDITMSG >actual &&
+	head -n 7 .git/COMMIT_EDITMSG >actual &&
 	test_cmp expect actual
 '
 
@@ -182,7 +181,7 @@ test_expect_success 'committer is automatic' '
 		# must fail because there is no change
 		test_must_fail git commit -e -m "sample"
 	) &&
-	head -n 9 .git/COMMIT_EDITMSG |	\
+	head -n 8 .git/COMMIT_EDITMSG |	\
 	sed "s/^# Committer: .*/# Committer:/" >actual &&
 	test_cmp expect actual
 '