diff --git a/Library/Homebrew/Gemfile.lock b/Library/Homebrew/Gemfile.lock
index 4082da7ab9..6a283b5a44 100644
--- a/Library/Homebrew/Gemfile.lock
+++ b/Library/Homebrew/Gemfile.lock
@@ -98,13 +98,13 @@ GEM
     rspec-support (3.9.3)
     rspec-wait (0.0.9)
       rspec (>= 3, < 4)
-    rubocop (0.90.0)
+    rubocop (0.91.0)
       parallel (~> 1.10)
       parser (>= 2.7.1.1)
       rainbow (>= 2.2.2, < 4.0)
       regexp_parser (>= 1.7)
       rexml
-      rubocop-ast (>= 0.3.0, < 1.0)
+      rubocop-ast (>= 0.4.0, < 1.0)
       ruby-progressbar (~> 1.7)
       unicode-display_width (>= 1.4.0, < 2.0)
     rubocop-ast (0.4.0)