对模拟对象的验证不尊重测试用例

Question

问题：

假设我们有两个不同的服务

class ServiceA(serviceB: ServiceB) {

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

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

我编写了两个测试方法并尝试验证是否调用了methodB。当我分别运行两个测试用例时，测试通过了。当我运行所有测试方法时，验证给出了第二次测试的错误结果。 在测试类上下文中，mockito-verification 记录对模拟对象的所有调用。我认为 mockito-scala 应该在每次测试后重置模拟对象的验证计数

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
  }
}

顺便说一句，我尝试了 mockito-core，它给出了同样的错误。

Answer 1

您的 serviceA 和 serviceB 对象实际上是测试装置，但您以错误的方式共享它们。使用像您这样的代码，所有测试都共享相同的对象，这意味着测试通过共享脏状态相互交互。 ScalaTest 支持多种方式share fixtures。一种更简洁的方法是loan pattern，如下所示：

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
  }
}

您也可以使用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
  }
}

但是恕我直言，这是一种作弊