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The Argument Is the (Mockito) Answer

Make a Method Return Values Based on Its Input Arguments

In this article:
* The Service I Want to Test
* Testing Approaches
* Setting Expectations
* Is There a Better Way?
* Simplifying the Test
* A More Elegant Solution
* Summing Up

For developers who prefer to watch a video rather than read a blog post, here a video covering this topic:

If, on the other hand, you prefer to read text, please continue. Of course, ideally you’ll enjoy doing both. :)

The Service I Want to Test

I am trying to test a service that saves a list of Person objects. In my case, the PersonService class has a method called savePeople that takes a vararg list of persons and saves them one by one:

public class PersonService {
    private final PersonRepository repository;

    public PersonService(PersonRepository repository) {
        this.repository = repository;
    }

    public List<Integer> savePeople(Person... person) {
        return Arrays.stream(person)…