diff --git a/Gemfile.lock b/Gemfile.lock
index f2d9add7..6ab6debf 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -144,7 +144,7 @@ GEM
     strscan (3.1.0)
     terminal-table (3.0.2)
       unicode-display_width (>= 1.1.1, < 3)
-    test-unit (3.6.3)
+    test-unit (3.6.4)
       power_assert
     tzinfo (2.0.6)
       concurrent-ruby (~> 1.0)