Merge branch 'as/describe-broken-refresh-index-fix'

"git describe --dirty --broken" forgot to refresh the index before
seeing if there is any chang, ("git describe --dirty" correctly did
so), which has been corrected.

* as/describe-broken-refresh-index-fix:
  describe: refresh the index when 'broken' flag is used

Author: gitster

builtin/describe.c

@@ -53,6 +53,10 @@ static const char *diff_index_args[] = {
 	"diff-index", "--quiet", "HEAD", "--", NULL
 };
 
+static const char *update_index_args[] = {
+	"update-index", "--unmerged", "-q", "--refresh", NULL
+};
+
 struct commit_name {
 	struct hashmap_entry entry;
 	struct object_id peeled;
@@ -645,6 +649,14 @@ int cmd_describe(int argc, const char **argv, const char *prefix)
 	if (argc == 0) {
 		if (broken) {
 			struct child_process cp = CHILD_PROCESS_INIT;
+
+			strvec_pushv(&cp.args, update_index_args);
+			cp.git_cmd = 1;
+			cp.no_stdin = 1;
+			cp.no_stdout = 1;
+			run_command(&cp);
+
+			child_process_init(&cp);
 			strvec_pushv(&cp.args, diff_index_args);
 			cp.git_cmd = 1;
 			cp.no_stdin = 1;

t/t6120-describe.sh

@@ -671,4 +671,40 @@ test_expect_success 'setup misleading taggerdates' '
 
 check_describe newer-tag-older-commit~1 --contains unique-file~2
 
+test_expect_success 'describe --dirty with a file with changed stat' '
+	test_when_finished "rm -fr stat-dirty" &&
+	git init stat-dirty &&
+	(
+		cd stat-dirty &&
+
+		echo A >file &&
+		git add file &&
+		git commit -m A &&
+		git tag A -a -m A &&
+		echo "A" >expect &&
+
+		test-tool chmtime -10 file &&
+		git describe --dirty >actual &&
+		test_cmp expect actual
+	)
+'
+
+test_expect_success 'describe --broken --dirty with a file with changed stat' '
+	test_when_finished "rm -fr stat-dirty" &&
+	git init stat-dirty &&
+	(
+		cd stat-dirty &&
+
+		echo A >file &&
+		git add file &&
+		git commit -m A &&
+		git tag A -a -m A &&
+		echo "A" >expect &&
+
+		test-tool chmtime -10 file &&
+		git describe --dirty --broken >actual &&
+		test_cmp expect actual
+	)
+'
+
 test_done