diff --git a/Library/.rubocop.yml b/Library/.rubocop.yml
index 2aba282c45..be2fb4a67a 100644
--- a/Library/.rubocop.yml
+++ b/Library/.rubocop.yml
@@ -139,6 +139,9 @@ Style/RegexpLiteral:
 Style/SpaceAroundOperators:
   Enabled: false
 
+Style/SingleLineBlockParams:
+  Enabled: false
+
 # not a problem for typical shell users
 Style/SpecialGlobalVars:
   Enabled: false
diff --git a/Library/Homebrew/cask/lib/hbc/utils.rb b/Library/Homebrew/cask/lib/hbc/utils.rb
index 88b8a88c4b..ef3e5eda37 100644
--- a/Library/Homebrew/cask/lib/hbc/utils.rb
+++ b/Library/Homebrew/cask/lib/hbc/utils.rb
@@ -147,7 +147,7 @@ module Hbc
     end
 
     def self.size_in_bytes(files)
-      Array(files).reduce(0) { |a, e| a + (File.size?(e) || 0) }
+      Array(files).reduce(0) { |acc, elem| acc + (File.size?(elem) || 0) }
     end
 
     def self.capture_stderr
diff --git a/Library/Homebrew/dev-cmd/boneyard-formula-pr.rb b/Library/Homebrew/dev-cmd/boneyard-formula-pr.rb
index 487f0c9dbe..3d95f14b9f 100644
--- a/Library/Homebrew/dev-cmd/boneyard-formula-pr.rb
+++ b/Library/Homebrew/dev-cmd/boneyard-formula-pr.rb
@@ -62,7 +62,7 @@ module Homebrew
       end
       tap_migrations = Utils::JSON.load(File.read(tap_migrations_path))
       tap_migrations[formula.name] = boneyard_tap.name
-      tap_migrations = tap_migrations.sort.inject({}) { |a, e| a.merge!(e[0] => e[1]) }
+      tap_migrations = tap_migrations.sort.inject({}) { |acc, elem| acc.merge!(elem[0] => elem[1]) }
       tap_migrations_path.atomic_write(JSON.pretty_generate(tap_migrations) + "\n")
     end
     unless which("hub") || local_only
diff --git a/Library/Homebrew/diagnostic.rb b/Library/Homebrew/diagnostic.rb
index 0b32f64c7c..19148a6ae2 100644
--- a/Library/Homebrew/diagnostic.rb
+++ b/Library/Homebrew/diagnostic.rb
@@ -69,7 +69,7 @@ module Homebrew
       end
 
       def inject_file_list(list, string)
-        list.inject(string) { |a, e| a << "  #{e}\n" }
+        list.inject(string) { |acc, elem| acc << "  #{elem}\n" }
       end
       ############# END HELPERS