diff --git a/Library/.rubocop_todo.yml b/Library/.rubocop_todo.yml
index 04a2cdd6e9..d044796fe8 100644
--- a/Library/.rubocop_todo.yml
+++ b/Library/.rubocop_todo.yml
@@ -288,13 +288,6 @@ Style/Semicolon:
   Exclude:
     - 'Homebrew/descriptions.rb'
 
-# Offense count: 1
-# Configuration parameters: Methods.
-# Methods: {"reduce"=>["a", "e"]}, {"inject"=>["a", "e"]}
-Style/SingleLineBlockParams:
-  Exclude:
-    - 'Homebrew/diagnostic.rb'
-
 # Offense count: 2
 # Cop supports --auto-correct.
 # Configuration parameters: SupportedStyles.
diff --git a/Library/Homebrew/diagnostic.rb b/Library/Homebrew/diagnostic.rb
index 8f158ddd81..62e916ce19 100644
--- a/Library/Homebrew/diagnostic.rb
+++ b/Library/Homebrew/diagnostic.rb
@@ -78,8 +78,8 @@ module Homebrew
         end
       end
 
-      def inject_file_list(list, str)
-        list.inject(str) { |s, f| s << "    #{f}\n" }
+      def inject_file_list(list, string)
+        list.inject(string) { |a, e| a << "    #{e}\n" }
       end
       ############# END HELPERS