tests DOC white space
diff --git a/tests/test_io.c b/tests/test_io.c
index 6b08f42..8c6fb67 100644
--- a/tests/test_io.c
+++ b/tests/test_io.c
@@ -8,7 +8,7 @@
  * This source code is licensed under BSD 3-Clause License (the "License").
  * You may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
- * 
+ *
  *     https://opensource.org/licenses/BSD-3-Clause
  */