Merge branch 'ob/sequencer-empty-hint-fix'

The use of API for consistency between two calls to
require_clean_work_tree() from the sequencer code has been cleaned
up.

* ob/sequencer-empty-hint-fix:
  sequencer: rectify empty hint in call of require_clean_work_tree()

Author: gitster

sequencer.c

@@ -6229,7 +6229,7 @@ int complete_action(struct repository *r, struct replay_opts *opts, unsigned fla
 	if (checkout_onto(r, opts, onto_name, &oid, orig_head))
 		goto cleanup;
 
-	if (require_clean_work_tree(r, "rebase", "", 1, 1))
+	if (require_clean_work_tree(r, "rebase", NULL, 1, 1))
 		goto cleanup;
 
 	todo_list_write_total_nr(&new_todo);

wt-status.c

@@ -2655,8 +2655,12 @@ int require_clean_work_tree(struct repository *r,
 	}
 
 	if (err) {
-		if (hint)
+		if (hint) {
+			if (!*hint)
+				BUG("empty hint passed to require_clean_work_tree();"
+				    " use NULL instead");
 			error("%s", hint);
+		}
 		if (!gently)
 			exit(128);
 	}