[每周软件]：Cucumber：Third Day

简介

OSChina 的链接 Cucumber

ruby 的 BDD框架，类似自然语言的DSL，适用于BDD模式和验收测试。

Book

The Rspec Book

The Cucumber Book

本系列所有内容取自The Rspec Book 虽标记原创 但其实我只是翻译总结了一下

Step Definition

参数

   Given a "150" tickets and "0" taken do |arg1,arg2|
        #arg1 and arg2 都是字符串类型！
    end

嵌套

你可以把一个Step继续划分，在Step Definition里继续定义

When /I transfer (.*) from (.*) to (.*)/ do |amount, source, target|
    steps %Q{
        When I select #{source} as the source account
        And I select #{target} as the target account
        And I set #{amount} as the amount
        And I click transfer
    }
end

Hooks

• Before: 每个Scenario之前执行

• After: 每个Scenario之后执行

• AfterStep: 每个Step之后执行

• 上面三个方法可以跟标签 例如 Before(@foo) 使用标签的规则跟标签规则一致
例子：

# -*- encoding : utf-8 -*-
class Hello
  def greet
    "Hello Cucumber!"
  end
end
Before do
  puts "Now im going to work!"
end
After do
  puts "Now i have finished my work!"
end
AfterStep do
  puts "I finish one step!"
end
Given /^如该我给了你一个测试的hello$/ do
  @hello = Hello.new
end

When /^当我给你一个greet的时候$/ do
  @message = @hello.greet
end

Then /^我应该看到 "(.*?)"$/ do |greeting|
  @message.should == greeting
end

执行结果：

$ cucumber features
    Feature: greeter says hello
      Cucumber的Hello World

      Scenario: 对世界打个招呼吧             # features/greeter_says_hello.feature:3
        Given 如该我给了你一个测试的hello       # features/step_definitions/g_steps.rb:16
          Now im going to work!
          I finish one step!
        When 当我给你一个greet的时候          # features/step_definitions/g_steps.rb:20
          I finish one step!
        Then 我应该看到 "Hello Cucumber!" # features/step_definitions/g_steps.rb:24
          I finish one step!

    1 scenario (1 passed)
    3 steps (3 passed)
    0m0.004s

Background

Background 是feature的hook （上面的是step definition里的hook）

例子如下：

Feature: invite friends
    Background: Logged in
        Given I am logged in as "Aslak"
        And the following people exist:
            | name| David |
            | friend? |yes|
            | Vidkun | no|
    Scenario: Invite someone who is already a friend
    Scenario: Invite someone who is not a friend
    Scenario: Invite someone who doesn't have an account

执行顺序是：Before–>Backgroun–>Scenario

Tables

 Scenario:Booking ticket
    When I need a table
      |name|number|
      |abc |1|
      |def |2|

一个Table传递过去是一个Cucumber::Ast::Table 一种类似Hash的结构 用ruby处理如下，其他语言也可以处理：

When /^I need a table$/ do |table|
    table.hashes.each do |hash|
      hash.each do |k,v|
        puts "#{k}:#{v}"
      end
    end
end

执行结果：

 Scenario: Booking ticket # features/say_good_night.feature:6
    When I need a table    # features/step_definitions/good_steps.rb:11
      name:abc
      number:1
      name:def
      number:2
      | name | number |
      | abc  | 1      |
      | def  | 2      |

1 scenario (1 passed)
1 step (1 passed)
0m0.006s

Outline

outline是处理类似的Scenario的时候使用的

比如：

Scenario: One Scenario
    Given the secret code is 1234
    When I guess 1234
    Then the mark should be bbbb

Scenario: Another Scenario
    Given the secret code is 1234
    When I guess 1235
    Then the mark should be bbb

可以用另一种形式写出来：

Scenario Outline: submit guess
    Given the secret code is "<code>"
    When I guess "<guess>"
    Then the mark should be "<mark>"
 Examples: all numbers correct
    | code |  guess | mark |
    | 1234 | 1234    | ++++ |
    | 1234 | 1243    | ++--  |
    | 1234 | 1423    | +---  |
    | 1234 | 4321    | ----    |

在这种情况下，cucumber会自动依次带入Scenarios里的table到Scenario Outline里来执行。

To Be Continued

明天Cucumber in Rails