Merge pull request #4183 from commitay/upgrade-cache

cask upgrade: ensure cache exists

Library/Homebrew/cask/lib/hbc/cli/upgrade.rb

@@ -82,6 +82,10 @@ module Hbc
       def self.help
         "upgrades all outdated casks"
       end
+
+      def self.needs_init?
+        true
+      end
     end
   end
 end