尝试在单元测试中验证 Groovy 闭包

Question

我正在尝试验证名为 CUTService 的 class 中的这个 groovy 闭包是否具有正确的值：

mailService.sendMail {
    to 'hey@example.com'
    from 'hey@example.com'
    subject 'Stuff'
    body 'More stuff'
}

我看过 https://github.com/craigatk/spock-mock-cheatsheet/raw/master/spock-mock-cheatsheet.pdf，但他的语法产生错误：

1 * mailService.sendMail({ Closure c -> c.to == 'hey@example.com'})

groovy.lang.MissingPropertyException: No such property: to for class: com...CUTService

我查看了 Is there any way to do mock argument capturing in Spock 并尝试了这个：

1 * mailService.sendMail({closure -> captured = closure })
assertEquals 'hey@example.com', captured.to

产生：

groovy.lang.MissingPropertyException: No such property: to for class: com...CUTService

我也试过这个：

1 * mailService.sendMail({captured instanceof Closure })
assertEquals 'hey@example.com', captured.to

产生：

Too few invocations for:
1 * mailService.sendMail({captured instanceof Closure })   (0 invocations)

...

Unmatched invocations (ordered by similarity):
1 * mailService.sendMail(com...CUTService$_theMethod_closure5@21a4c83b)

我需要做什么才能让它正常工作？

Answer 1

当你写：

mailService.sendMail {
    to 'hey@example.com'
    from 'hey@example.com'
    subject 'Stuff'
    body 'More stuff'
}

实际上，您正在执行方法 sendMail，并带有闭包 c。 sendMail 创建一个委托，并用这个委托调用你的闭包。您的闭包实际上执行为：

delegate.to('hey@example.com')
delegate.from('hey@example.com')
delegate.subject('Stuff')
delegate.body('More stuff')

要测试这个闭包，您应该创建一个模拟，将闭包的委托配置到这个模拟，调用闭包，并验证模拟期望。

因为这个任务不是很简单，所以最好重用邮件插件并创建自己的邮件生成器：

given:
  def messageBuilder = Mock(MailMessageBuilder)

when:
   // calling a service

then: 
    1 * sendMail(_) >> { Closure callable ->
      callable.delegate = messageBuilder
      callable.resolveStrategy = Closure.DELEGATE_FIRST
      callable.call(messageBuilder)
   }
   1 * messageBuilder.to("hey@example.com")
   1 * messageBuilder.from("hey@example.com")

尝试在单元测试中验证 Groovy 闭包

Trying to validate Groovy closure in a unit test

groovy

unit-testing

spock