模拟对象与测试用例无关的验证

Question

class ServiceA(serviceB: ServiceB) {

  def methodA(): String = {
    "methodA called"
    serviceB.methodB()
  }

  def methodA2(): String = {
    "methodA2 called"
    serviceB.methodB()
  }
}

class ServiceATest extends FlatSpec with IdiomaticMockito {
  val serviceB: ServiceB = mock[ServiceB]
  val serviceA: ServiceA = new ServiceA(serviceB)
  "methodA" should "called" in {
    serviceA.methodA()
    serviceB.methodB wasCalled once // Passes
  }
  "methodA2" should "called" in {
    serviceA.methodA2()
    serviceB.methodB wasCalled once // Fail. was 2 times
  }
}

Answer 1

您的ServiceA和ServiceB对象实际上是测试夹具，但您以错误的方式共享它们。与您的代码一样，相同的对象由所有测试共享，这意味着测试通过共享的脏状态彼此交互。ScalaTest支持多种共享固定装置的方法。其中一种更干净的方法是贷款模式，如：

class ServiceATest extends FlatSpec with IdiomaticMockito {

  def withServicesAandBMock(testCode: (ServiceA, ServiceB) => Any) {
    val serviceB: ServiceB = mock[ServiceB]
    val serviceA: ServiceA = new ServiceA(serviceB)
    testCode(serviceA, serviceB)
  }

  "methodA" should "called" in withServicesAandBMock { (serviceA, serviceB) =>
    serviceA.methodA()
    serviceB.methodB wasCalled once // Passes
  }

  "methodA2" should "called" in withServicesAandBMock { (serviceA, serviceB) =>
    serviceA.methodA2()
    serviceB.methodB wasCalled once // now passes as well
  }
}

或者，您可以使用resetmocksaftereachtest

class ServiceATest extends FlatSpec with IdiomaticMockito with ResetMocksAfterEachTest {

  val serviceB: ServiceB = mock[ServiceB]
  val serviceA: ServiceA = new ServiceA(serviceB)
  "methodA" should "called" in {
    serviceA.methodA()
    serviceB.methodB wasCalled once // Passes
  }
  "methodA2" should "called" in {
    serviceA.methodA2()
    serviceB.methodB wasCalled once // now passes as well
  }
}

但这是一种欺骗