假设我们要测试以下函数
fun loadData(dataId: Long, completion: (JsonElement?, Exception?) -> Unit) {
underlayingApi.post(url = "some/rest/url",
completion = { rawResult, exception ->
val processedResult = processJson(rawResult)
completion(processedResult, exception)
})
}
我很清楚如何模拟、注入、存根和验证对underlayingApi的调用.
How to verify the result returned via completion(processedResult, exception)?
为了测试lambdas行为，必须模拟underlayingApi，其中lambda是通过InvoactionOnMock对象调用的，如下所示.
`when`(underlayingApi.post(eq("some/rest/url"),
any())).thenAnswer {
val argument = it.arguments[1]
val completion = argument as ((rawResult: String?, exception: Exception?) -> Unit)
completion.invoke("result", null)
}
This leads to the invocation of the callback within the object under test. Now to check if the callback out of the object under test is working verify it like that.
objUnderTest.loadData(id,
{ json, exception ->
assert....
})