Kotlin Mocked suspend lambda在Mockito中返回null

依赖关系：

testImplementation "androidx.arch.core:core-testing:2.0.0"
testImplementation 'org.mockito:mockito-core:3.3.0'
testImplementation 'org.mockito:mockito-inline:2.8.47'
testImplementation "com.nhaarman.mockitokotlin2:mockito-kotlin:2.2.0"

fun <T : Any> doSomething(
    result: Result<T>,
    callback: Callback<T>? = null
) {

    when (result.status) {
        Result.Status.SUCCESS -> {
            callback?.success(result.data)
        }
        Result.Status.ERROR -> {
            callback?.error(result)
        }
    }
}

suspend fun <T : Any> handleCall(
    call: suspend () -> Result<T>,
    callback: Callback<T>? = null
) {
    doSomething(call.invoke(), object : Callback<T> {
        override fun success(t: T?) {
            callback?.success(t)
        }

        override fun error(result: Result<T>) {
            ...
            callback?.error(result)
        }
    })
}

fun testHandleCallSuccess() {

    val call = mock<suspend () -> Result<Int>>()
    val callback = Mockito.mock(Callback::class.java) as Callback<Int>
    runBlocking {
        whenever(call.invoke()).thenReturn(Result.success(0))
        baseViewModel.handleCall(call, callback)
    }
    verify(callback).success(0)
}

视图模型：

testImplementation "androidx.arch.core:core-testing:2.0.0"
testImplementation 'org.mockito:mockito-core:3.3.0'
testImplementation 'org.mockito:mockito-inline:2.8.47'
testImplementation "com.nhaarman.mockitokotlin2:mockito-kotlin:2.2.0"

fun <T : Any> doSomething(
    result: Result<T>,
    callback: Callback<T>? = null
) {

    when (result.status) {
        Result.Status.SUCCESS -> {
            callback?.success(result.data)
        }
        Result.Status.ERROR -> {
            callback?.error(result)
        }
    }
}

suspend fun <T : Any> handleCall(
    call: suspend () -> Result<T>,
    callback: Callback<T>? = null
) {
    doSomething(call.invoke(), object : Callback<T> {
        override fun success(t: T?) {
            callback?.success(t)
        }

        override fun error(result: Result<T>) {
            ...
            callback?.error(result)
        }
    })
}

fun testHandleCallSuccess() {

    val call = mock<suspend () -> Result<Int>>()
    val callback = Mockito.mock(Callback::class.java) as Callback<Int>
    runBlocking {
        whenever(call.invoke()).thenReturn(Result.success(0))
        baseViewModel.handleCall(call, callback)
    }
    verify(callback).success(0)
}

---

调用调用.invoke（）时，该函数不起作用，始终返回null。

是否有理由使用

回调

而不是高阶函数？实际上，它可能是高阶函数。但我认为这在这个问题上无关紧要=）