code: def redis_mock(replies = {})
        begin
          pid = fork do
            trap("TERM") { exit }
  
            RedisMock.start do |command, *args|
              (replies[command.to_sym] || lambda { |*_| "+OK" }).call(*args)
            end
          end
  
          sleep 1 # Give time for the socket to start listening.
  
          yield
  
        ensure
          if pid
            Process.kill("TERM", pid)
            Process.wait(pid)
          end
        end
      end
docs: Forks the current process and starts a new mock Redis server on
   port 6380.
  
   The server will reply with a `+OK` to all commands, but you can
   customize it by providing a hash. For example:
  
       redis_mock(:ping => lambda { "+PONG" }) do
         assert_equal "PONG", Redis.new(:port => 6380).ping
       end