你如何使用rspec测试分叉的代码

Question

我有以下代码

  def start_sunspot_server
    unless @server
      pid = fork do
        STDERR.reopen("/dev/null")
        STDOUT.reopen("/dev/null")
        server.run
      end

      at_exit { Process.kill("TERM", pid) }

      wait_until_solr_starts
    end
  end

我如何有效地使用rspec进行测试？

我在想什么

Kernel.should_receive(:fork)
STDERR.should_receive(:reopen).with("/dev/null")
STDOUT.should_receive(:reopen).with("/dev/null")
server.should_receive(:run)

等等

Answer 1

我对你的例子中的@server实例变量和server方法感到困惑,但是这里有一个例子可以帮助你到达你想去的地方:

class Runner
  def run
    fork do
      STDERR.reopen("/dev/null")
    end
  end
end

describe "runner" do
  it "#run reopens STDERR at /dev/null" do
    runner = Runner.new

    runner.should_receive(:fork) do |&block|
      STDERR.should_receive(:reopen).with("/dev/null")
      block.call
    end

    runner.run
  end
end

关键是fork消息被发送到Runner对象本身,即使它的实现在Kernel模块中.

HTH,大卫