如何模拟Scala单身对象？

[error]    MockitoException: : 
[error] Cannot mock/spy class play.api.libs.ws.WS$
[error] Mockito cannot mock/spy following:
[error]   - final classes
[error]   - anonymous classes
[error]   - primitive types  (GeolocationSpec.scala:18)

阅读here,似乎Scalamock允许这样做：

To mock a standalone singleton object,use
org.scalamock.annotation.mockObject.

我的服务组件是这样的：

trait GeolocationService {
  def wsClient = WS
  def getPath(origin: Location,destination: Location): Future[Route]
}

class DefaultGeolocationService extends GeolocationService {

  val serviceProviderEndpoint = Play.current.configuration.getString("api.directions.endpoint")

  override def getPath(origin: Location,destination: Location): Future[Route] = {

    val params = Seq(
      "origin" -> s"${origin.lat},${origin.lon}","destination" -> s"${destination.lat},${destination.lon}"
    );
    val resp = wsClient.url(serviceProviderEndpoint.get).withQueryString(params: _*).get()
    resp.map {
      // omitted code
    }
  }
}

我的build.sbt具有所有这些依赖关系：

[...]
"org.scalatest" %% "scalatest" % "2.2.1","org.specs2" %% "specs2" % "2.3.13" % "test","org.scalamock" %% "scalamock-specs2-support" % "3.0.1" % "test","org.scalamock" %% "scalamock-scalatest-support" % "3.0.1" % "test","org.scalamock" %% "scalamock" % "3.0.1",[...]

但我找不到这个：org.scalamock.annotation.mockObject

也许这也可以使用EasyMock和PowerMock,但是我找不到任何Scala示例代码.

任何想法？