Question

当我遇到some issue时，我决定检查执行before和after个挂钩的顺序。这就是我所做的：

require "spec_helper"

describe "The order:" do

  before(:all) {
    puts "before_all"
  }

  after(:all) {
    puts "after_all"
  }

  before(:each) {
    puts "before_each"
  }

  after(:each) {
    puts "after_each"
  }

  describe "DESC A" do
    before {
      puts "A_before"
    }
    it "A_it_1" do      
      expect(1).to eq(1)
    end
    it "A_it_2" do
      expect(1).to eq(1)
    end
  end

  describe "DESC B" do
    before {
      puts "B_before"
    }
    it "B_it_1" do      
      expect(1).to eq(1)
    end
    it "B_it_2" do
      expect(1).to eq(1)
    end
  end  
end

以及我得到了什么：

The order:

before_all

  DESC A
before_each
A_before
after_each
    A_it_1
before_each
A_before
after_each
    A_it_2
  DESC B
before_each
B_before
after_each
    B_it_1
before_each
B_before
after_each
    B_it_2

after_all

这里发生了什么？为什么after_each在A_it_1之前运行？

更新

添加around(:each)会更有趣：

 around(:each) do |example|
    puts "around_in"
    example.run
    puts "around_out"
  end

和结果：

The order:
before_all
  DESC A
around_in
before_each
A_before
after_each
around_out
    A_it_1
around_in
before_each
A_before
after_each
around_out
    A_it_2
  DESC B
around_in
before_each
B_before
after_each
around_out
    B_it_1
around_in
before_each
B_before
after_each
around_out
    B_it_2
after_all

Answer 1

您的输出以及relishapp.com上记录的官方输出是正确的。发生的事情是rspec需要在每个示例之后运行after（：each）es，因为after（：each）中的异常会导致示例失败。在rspec可以在输出中显示示例之前，它需要知道它是绿色还是红色，这意味着在示例的描述出现在输出之前需要运行after（：eaches）。

但是，如果在实际示例中放置了puts语句，您将看到before（：each）es出现在它之前，然后运行示例代码（包括puts），然后是after（：each） es，正如您所期望的那样，最后，示例的描述将输出到屏幕。

和你一样，我也很困惑，直到我意识到rspec打印出的示例标签与它实际做的事情并不一致 - 标签只会打印出来之前（：all）s，before（：each）es和after（：each）之后运行示例。

注意：在打印完示例标签后运行（：all）之后运行，因为它们不会影响测试结果（生成警告，表示在after（：all）挂钩中发生异常，但是这不会使测试变红。）

Answer 2

RSpec's documentation for before and after hooks指定它们运行的顺序。但是，RSpec's documentation for around hooks未指定其运行顺序。

此规范测试执行around，before和after :all和:each以及示例的顺序。当我使用rspec（-core）2.14.8运行它时，它们按照你期望的顺序执行：

describe "order in which rspec around/before/after hooks run" do
  before :all do
    defined?($previous_hook).should be_false # this hook runs first
    $previous_hook = "before :all"
  end

  around :each do |example|
    $previous_hook.should == "before :all"
    $previous_hook = "around :each 1"
    example.run
    $previous_hook.should == "after :each"
    $previous_hook = "around :each 2"
  end

  before :each do
    $previous_hook.should == "around :each 1"
    $previous_hook = "before :each"
  end

  it "should not raise an exception or print anything" do
    $previous_hook.should == "before :each"
    $previous_hook = "example"
  end

  after :each do
    $previous_hook.should == "example"
    $previous_hook = "after :each"
  end

  after :all do
    # rspec ignores assertion failures and any other exceptions raised here, so all we can do is puts.
    # $previous_hook is a global because if it's an instance variable it is "before :all" at this point.
    warn "Previous hook was #{$previous_hook}, NOT around :each 2 as expected" unless $previous_hook == "around :each 2"
  end

end

注意一些可能令人惊讶的事情：

self在:all和:each块中有所不同，因此我需要使用全局变量而不是实例变量。
after :all（但不是before :all）吃异常。
查看所有这些地方.should的作品！并不是说你通常想在那里使用它。

Answer 3

上面已经回答了这个问题，但是添加了一个简单的答案。

要查看钩子以什么顺序运行，还必须在“ it”中添加“ puts”语句

所以

describe "The order:" do

  before(:all) {
    puts "before_all"
  }

  after(:all) {
    puts "after_all"
  }

  before(:each) {
    puts "before_each"
  }

  after(:each) {
    puts "after_each"
  }

  describe "DESC A" do
    before {
      puts "A_before"
    }
    it "A_it_1" do      
      # expect(1).to eq(1)       <<<<---- Change Here
      puts "Inside the test"
    end
  end
end

RSpec在钩子之前，之后和周围以什么顺序运行？

3 个答案: