# File lib/grit/git-ruby/repository.rb, line 535
      def files_changed?(tree_sha1, tree_sha2, path_limiter = nil)
        if path_limiter
          mod = quick_diff(tree_sha1, tree_sha2)
          files = mod.map { |c| c.first }
          path_limiter.to_a.each do |filepath|
            if files.include?(filepath)
              return true
            end
          end
          return false
        end
        true
      end