ScalaMock 模拟通用 Java 接口重载方法

Question

我正在尝试模拟 Java 具有不同参数数量的重载方法的通用接口。接口代码为：

import java.util.concurrent.Callable;

public interface GOInterface<T> {
    void send(T record);
    void send(T record, Callable<T> onComplete);
}

我尝试使用 onComplete 功能模拟发送，如下所示：

进口java.util.concurrent.Callable

import org.scalamock.scalatest.MockFactory
import org.scalatest.{FlatSpec, Matchers}

class JavaInterfaceTest extends FlatSpec with Matchers with MockFactory {
  behavior of "scalamock"

  it should "mock java generic interface with overloaded method (with different number of parameters)" in {
    var result = ""
    val m = mock[GOInterface[String]]
    (m.send(_: String, _: Callable[String])).expects(*, *)
      .onCall{ case(s: String, c: Callable[String]) => c.call()}.once

    m.send("hello", new Callable[String] {
      override def call(): String = {result = "world"; result}
    })

    result should be("world")
  }


  it should "mock java generic interface with overloaded method (with different number of parameters) 2" in {
    var result = ""
    val m = mock[GOInterface[String]]
    (m.send(_: String)).expects(*).once

    m.send("hello")

    result should be("")
  }
}

我从编译器得到的错误是：

error: value expects is not a member of (String, java.util.concurrent.Callable[String]) => Unit
[ERROR]     (m.send(_: String, _: Callable[String])).expects(*, *)
[ERROR]                                              ^

error: value expects is not a member of String => Unit
[ERROR]     (m.send(_: String)).expects(*).once
[ERROR]

查看 ScalaMock 的不同示例 git 我可以看到没有测试使用具有不同参数计数的重载方法检查通用接口。

我的依赖项是：

        <dependency>
            <groupId>org.scalamock</groupId>
            <artifactId>scalamock-scalatest-support_2.11</artifactId>
            <version>3.6.0</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.scalamock</groupId>
            <artifactId>scalamock-core_2.11</artifactId>
            <version>3.6.0</version>
            <scope>test</scope>
        </dependency>

我同时在 ScalaMock 存储库中创建了一个 bug。

Answer 1

首先，我建议升级到最新版本的 ScalaMock，但可能也存在关于泛型和重载的极端情况。

要解决这个问题，在很多情况下，先锁定类型，然后再创建模拟会有所帮助：

trait StringGoInterface extends GoInterface[String]
val m = mock[StringGoInterface]

Answer 2

我设法克服了这个问题。不是以最干净的方式，而是它的作品。正如@PhilippM 建议我需要修复类型，但不幸的是这还不够，我需要创建一个虚拟 class。这是对我有用的解决方案：

class JavaInterfaceTest extends FlatSpec with Matchers with MockFactory {
  behavior of "scalamock"

  class StringInterface extends GOInterface[String] {
    override def send(record: String): Unit = ()

    override def send(record: String, onComplete: Callable[String]): Unit = ()
  }

  val call: (String, Callable[String]) => Unit = { case(s: String, c: Callable[String]) => c.call()}

  it should "mock java generic interface with overloaded method (with different number of parameters)" in {
    var result = ""
    val m = mock[StringInterface]
    (m.send(_: String, _: Callable[String])).expects(*, *)
      .onCall{ call }.once

    m.send("hello", new Callable[String] {
      override def call(): String = {result = "world"; result}
    })

    result should be("world")
  }


  it should "mock java generic interface with overloaded method (with different number of parameters) 2" in {
    var result = ""
    val m = mock[StringInterface]
    (m.send(_: String)).expects(*).once

    m.send("hello")

    result should be("")
  }
}

我觉得这有点难看，当需要模拟更复杂的接口时，这可能是最糟糕的，但我希望它对其他人有所帮助。

ScalaMock 模拟通用 Java 接口重载方法

ScalaMock mocking generic Java interface overloaded method

java

generics

unit-testing

scala

scalamock