模拟一个没有参数但带有隐式参数的方法

Question

abstract trait MyApi {

  def getResult()(implicit ec: ExecutionContext): Future[String]

}

以下不有效：

val m = mock[MyApi]
(m.getResult _).expects() returning "..."

它失败了：

java.lang.ClassCastException: org.scalamock.MockFunction1 cannot be cast to org.scalamock.MockFunction0

注：http://scalamock.org/user-guide/advanced_topics/ is only useful if the method has at least one argument. So we can't use the solution as in mocking methods which use ClassTag in scala using scalamock

中给出的例子

Answer 1

我猜你没有看到正确的例子。查看示例 4 的隐式参数：

class Codec()

trait Memcached {
  def get(key: String)(implicit codec: Codec): Option[Int]
}

val memcachedMock = mock[Memcached]

implicit val codec = new Codec
(memcachedMock.get(_ : String)(_ : Codec)).expects("some_key", *).returning(Some(123))

在你的例子中，当然，非隐式参数是空的，所以你想要：

(m.getResult()(_: ExecutionContext)).expects(*) returning "..."

Answer 2

只是为了完成案件。如果有人试图用更多的参数做同样的事情，片段如下：

trait MemcachedV2 {
   def get(key: String, value: String)(implicit codec: Codec): Option[Int]
}

val memcachedMock2 = mock[MemcachedV2]

(memcachedMock2.get(_, _)(_))
   .expects("some_key","another value", *)
   .returning(Some(123))

模拟一个没有参数但带有隐式参数的方法

Mock a method without arguments but with implicit parameters

unit-testing

scala

scalatest

scalamock