We need to use mock-maker-inline to mock final classes of some third party library (e.g. Azure SDK).

We are using below versions of scalatest and mockito:

scalaVersion := "2.12.2"

val ScalaTestVersion              = "3.2.5"
val ScalaCheckVersion             = "1.14.2"
val MockitoVersion                = "3.4.0"
val DockerItVersion               = "0.9.9"
val MockJavaMailVersion           = "1.9"
val MockitoScalaVersion           = "1.1.4"
val ScalaPlusScalaCheckVersion    = "3.2.2.0"
val ScalaPlusMockitoVersion       = "3.2.10.0"


lazy val MockitoIssueSample = (project in file("."))
  .settings(
    name := "MockitoIssueSample",
    libraryDependencies  = "org.scalatest" %% "scalatest" % ScalaTestVersion % Test,
    libraryDependencies  = "org.scalacheck"                %% "scalacheck"               % ScalaCheckVersion % Test,
    libraryDependencies  = "org.mockito"                   %  "mockito-core"             % MockitoVersion  % Test,
    libraryDependencies  = "org.mockito"                   %% "mockito-scala"            % MockitoScalaVersion  % Test,
    libraryDependencies  = "org.scalatestplus"             %% "scalacheck-1-14"          % ScalaPlusScalaCheckVersion  % Test,
    libraryDependencies  = "org.scalatestplus"             %% "mockito-3-4"              % ScalaPlusMockitoVersion  % Test,
  )

After enabling mock-maker-inline in our Scala application, other test cases which are using trait having final methods are started to fail with below error:

[info] - should should invoke area of the appropriate shape *** FAILED ***
[info]   org.mockito.exceptions.misusing.UnnecessaryStubbingException: Unnecessary stubbings detected.
[info] Clean & maintainable test code requires zero unnecessary code.
[info] Following stubbings are unnecessary (click to navigate to relevant line of code):
[info]   1. -> at cortex.mockito.sample.AreaCalculatorSpec$$anon$1.<init>(AreaCalculatorSpec.scala:27)
[info] Please remove unnecessary stubbings or use 'lenient' strictness. More info: javadoc for UnnecessaryStubbingException class.
[info]   at scala.runtime.java8.JFunction0$mcV$sp.apply(JFunction0$mcV$sp.java:12)
[info]   at scala.Option.fold(Option.scala:158)
[info]   at cortex.mockito.sample.AreaCalculatorSpec.withFixture(AreaCalculatorSpec.scala:13)
[info]   at org.scalatest.wordspec.AnyWordSpecLike.invokeWithFixture$1(AnyWordSpecLike.scala:1075)
[info]   at org.scalatest.wordspec.AnyWordSpecLike.$anonfun$runTest$1(AnyWordSpecLike.scala:1087)
[info]   at org.scalatest.SuperEngine.runTestImpl(Engine.scala:306)
[info]   at org.scalatest.wordspec.AnyWordSpecLike.runTest(AnyWordSpecLike.scala:1087)
[info]   at org.scalatest.wordspec.AnyWordSpecLike.runTest$(AnyWordSpecLike.scala:1069)
[info]   at org.scalatest.wordspec.AnyWordSpec.runTest(AnyWordSpec.scala:1879)
[info]   at org.scalatest.wordspec.AnyWordSpecLike.$anonfun$runTests$1(AnyWordSpecLike.scala:1146)
[info]   ...

We have simulated this issue with test Scala application. If we disable mock-maker-inline then this test case works. Here, in this sample application we have added just single problematic test case.

Below is sample code:

1. Shape.scala

   package mockito.sample

   trait Shape {

   final def printArea(): Unit = { println(s"Area is: $getArea()") }

   def getArea(): Double

   }

2. Rectangle.scala

   package mockito.sample

   class Rectangle(l: Long, b: Long) extends Shape {

   override def getArea(): Double = { l * b }

   }

3. AreaCalculator.scala

   package mockito.sample

   class AreaCalculator(shape: Shape) {

   def printArea(): Boolean = { shape.printArea() true }

   }

4. AreaCalculatorSpec.scala

   package mockito.sample

   import org.mockito.integrations.scalatest.IdiomaticMockitoFixture

   import org.scalatest.concurrent.ScalaFutures

   import org.scalatest.matchers.must.Matchers.convertToAnyMustWrapper

   import org.scalatest.matchers.should.Matchers

   import org.scalatest.wordspec.AnyWordSpec

   import org.scalatest.{EitherValues, TryValues}

   import org.scalatestplus.scalacheck.ScalaCheckPropertyChecks

   class AreaCalculatorSpec extends AnyWordSpec with Matchers with ScalaFutures with EitherValues with TryValues with IdiomaticMockitoFixture with ScalaCheckPropertyChecks {

   trait Setup { val rectangle = mock[Rectangle] val areaCalculator = new AreaCalculator(rectangle) }

   "AreaCalculator#printArea" should { "should invoke area of the appropriate shape" in new Setup { rectangle.getArea() shouldReturn 40.0 areaCalculator.printArea() mustBe true } }

   }

Please check and suggest your valuable inputs. Let me know if any other details are required.

Thank you,

Rakesh Dhandhukiya

CodePudding user response：

Can you update mockito and scalatest to the latest versions ? I tried reproducing the error but the test passes in my case. How are you disabling the mock-maker-inline ?

It appears IdiomaticMockitoFixture is deprecated and you should use IdiomaticMockito.

However, I do get this warning when adding mock-maker-inline:

OpenJDK 64-Bit Server VM warning: Sharing is only supported for boot loader classes because bootstrap classpath has been appended

It seems to be a harmless warning. Even though I disabled my

My build.sbt:

libraryDependencies  = "org.scalatest" %% "scalatest" % "3.2.12" % Test
libraryDependencies  = "org.scalamock" %% "scalamock" % "5.2.0" % Test
libraryDependencies  = "org.scalatestplus" %% "scalacheck-1-16" % "3.2.12.0" % Test
libraryDependencies  = "org.scalatestplus" %% "mockito-4-5" % "3.2.12.0" % Test
libraryDependencies  = "org.mockito" % "mockito-core" % "4.6.1" % Test
libraryDependencies  = "org.mockito" %% "mockito-scala" % "1.17.7" % Test