Chefspec - 预期的异常但没有提出

Question

我的食谱代码

bash 'capture-aide-output' do
  code <<-EOH
   aide --check | grep differences | tee /tmp/output.txt
  EOH
end

ruby_block 'check-output' do
  block do
    output_file = '/tmp/output.txt'
    if File.exist?(output_file) && File.read(output_file).include?('differences')
      raise('Halting Converge')
    else
      Chef::Log.info("Aide check output does not contain 'differences', proceeding converge")
    end
    if ::File.exist?(output_file)
      ::File.delete(output_file)
      Chef::Log.info("Deleted #{output_file}")
    end
  end
end

对应的chefspec代码

require 'spec_helper'
require 'chefspec'

describe 'your_cookbook::your_recipe' do
  let(:chef_run) { ChefSpec::SoloRunner.new.converge(described_recipe) }

  context 'when the output file contains differences' do
    before do
      allow(File).to receive(:exist?).with('/tmp/output.txt').and_return(true)
      allow(File).to receive(:read).with('/tmp/output.txt').and_return('differences')
    end

    it 'raises an exception and halts the converge' do
      expect { chef_run }.to raise_error(RuntimeError, 'Halting Converge')      
    end
  end
end 

Chefspec 测试，抛出以下错误。

Failures:
1) your_cookbook::your_recipe , when the output file contains differences
  Failures/Error: expect { chef_run }.to raise_error 'Halting Converge'
  expected Exception with "Halting Converge" but nothing was raised

你能帮忙找出我在 ChefSpec 测试中遗漏了什么不起作用吗