1 files changed, 2 insertions, 0 deletions
diff --git a/lib/diff.rb b/lib/diff.rb
index 90adc7e33..30bba39a0 100644
--- a/lib/diff.rb
+++ b/lib/diff.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: false
+
 module RedmineDiff
   class Diff