单元测试：如何验证参数是否传递给构造函数？

Question

I have the following code on my Android application:

public Observable<Person> execute(MyObject myObject) {
    return service.execute(new MyApiRequest(myObject));
}

What I want to test, using Mockito is that the same instance of MyObject is passed to MyApiRequest constructor. Let's say we don't know how MyApiRequest looks. I only want to test that there "myObject" param from execute() method is the same as MyApiRequest recieves.

Answer 1

Yes, you can use an ArgumentCaptor to inspect the MyApiRequest that comes back.

// Create the object and the captor.
ArgumentCaptor<MyApiRequest> myApiRequestCaptor =
    ArgumentCaptor.forClass(MyApiRequest.class);
MyObject myObject = new MyObject();

// Run the test.
systemUnderTest.execute(myObject);

// Capture the MyApiRequest.
verify(service).execute(myApiRequestCaptor.capture());
MyApiRequest myApiRequest = myApiRequestCaptor.getValue();

// Now check the object identity.
assertSame("MyApiRequest should have the exact same passed-in object.",
    myObject, myApiRequest.getParameter());