itAnswers should allow original Mockito Answer types

[jpopadak]

In order to return the first argument using the infix notations, this is what I am required to do without any additional functions:

When calling questionService.updateQuestion(any()) itAnswers { it.getArgument(0) }

Rather, in the original Mockito or even in com.nhaarman:mockito-kotlin I can do this notation:

whenever(questionService.updateQuestion(any())).then(returnsFirstArg<Question>())

In order to achieve this, I must use the following function that should be added to your API:

infix fun <T> OngoingStubbing<T>.itAnswers(value: Answer<T>): OngoingStubbing<T> = this.thenAnswer(value)

You could also include these to make the grammar more accurate with the arguments:

fun <T> withFirstArg(): Answer<T> = org.mockito.AdditionalAnswers.returnsFirstArg()
fun <T> withSecondArg(): Answer<T> = org.mockito.AdditionalAnswers.returnsSecondArg()
fun <T> withThirdArg(): Answer<T> = org.mockito.AdditionalAnswers.returnsArgAt(3)
fun <T> withFourthArg(): Answer<T> = org.mockito.AdditionalAnswers.returnsArgAt(4)
fun <T> withLastArg(): Answer<T> = org.mockito.AdditionalAnswers.returnsLastArg()

The combination of this all allows me to do the following:

When calling questionRepo.save(any(Question::class)) itAnswers withFirstArg()

[MarkusAmshove]

I've just released v1.32 which contains these changes 👍