brew style --fix (and a manual one)

Library/Homebrew/cask/cask_loader.rb

@@ -59,7 +59,7 @@ module Cask
 
       attr_reader :token, :path
 
-      def initialize(path)
+      def initialize(path) # rubocop:disable Lint/MissingSuper
         path = Pathname(path).expand_path
 
         @token = path.basename(path.extname).to_s

Library/Homebrew/extend/pathname.rb

@@ -418,7 +418,7 @@ class Pathname
   def install_metafiles(from = Pathname.pwd)
     Pathname(from).children.each do |p|
       next if p.directory?
-      next if File.zero?(p)
+      next if File.empty?(p)
       next unless Metafiles.copy?(p.basename.to_s)
 
       # Some software symlinks these files (see help2man.rb)