RSpec之前,之后和周围的顺序是以什么顺序运行的？

Question

当我遇到一些问题时,我决定检查执行的顺序before和after挂钩.这就是我做的:

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

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要跑A_it_1？

更新:

添加around(:each)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

RSpec 的关于before和after钩子的文档指定了它们运行的​​顺序。但是，RSpec 的around钩子文档没有指定它们运行的​​顺序。

该规范试验中，顺序around，before和after :all和:each，和实例，执行。当我使用 rspec(-core) 2.14.8 运行它时，它们会按照您期望的顺序执行：

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:all和:each块不同，所以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。
• 看看所有这些地方都.should有效！并不是说您通常想在那里使用它。

Answer 2

您的输出和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,这意味着需要在示例的描述出现在输出之前运行after(:eaches).

但是,如果在实际示例中放置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,只是正如您所期望的那样,最后,示例的描述输出到屏幕.

和你一样,我也很困惑,直到我意识到rspec打印出的例子的标签与它实际做的不一致 - 标签只在所有之前(:all)s,之前(:每个)打印出来es,以及在(:each)之后运行示例.

注意:在打印完示例标签之后运行(: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,但这不是让测试变红).