on official repository of Retrofit there's an example which can be useful:
https://github.com/square/retrofit/tree/master/retrofit-mock
I've also found: https://touk.pl/blog/2014/02/26/mock-retrofit-using-dagger-and-mockito/
Here you would find this fragment:
Unit Tests
During develop of app, you can send requests the server all time(or
most of time) so it is possible to live without mocked server, it
sucks but is possible. Unfortunately you are not able to write good
tests without the mock. Below there are two unit tests. Actually they
do not test anything but in simple way shows how to mock Retrofit
service using Mockito
and Dagger
.
@RunWith(RobolectricTestRunner.class)
public class EchoServiceTest {
@Inject
protected EchoService loginService;
@Inject
protected Client client;
@Before
public void setUp() throws Exception {
Injector.add(new AndroidModule(),
new RestServicesModule(),
new RestServicesMockModule(),
new TestModule());
Injector.inject(this);
}
@Test
public void shouldReturnOfferInAsyncMode() throws IOException {
//given
int expectedQuantity = 765;
String responseContent = "{" +
" \"message\": \"mock message\"," +
" \"quantity\": \"" + expectedQuantity + "\"" +
"}";
mockResponseWithCodeAndContent(200, responseContent);
//when
EchoResponse echoResponse = loginService.getMessageAndQuantity("test", "test");
//then
assertThat(echoResponse.getQuantity()).isEqualTo(expectedQuantity);
}
@Test
public void shouldReturnOfferInAsyncModea() throws IOException {
//given
int expectedQuantity = 2;
String responseContent = "{" +
" \"message\": \"mock message\"," +
" \"quantity\": \"" + expectedQuantity + "\"" +
"}";
mockResponseWithCodeAndContent(200, responseContent);
//when
EchoResponse echoResponse = loginService.getMessageAndQuantity("test", "test");
//then
assertThat(echoResponse.getQuantity()).isEqualTo(expectedQuantity);
}
protected void mockResponseWithCodeAndContent(int httpCode, String content) throws IOException {
Response response = createResponseWithCodeAndJson(httpCode, content);
when(client.execute(Matchers.anyObject())).thenReturn(response);
}
private Response createResponseWithCodeAndJson(int responseCode, String json) {
return new Response(responseCode, "nothing", Collections.EMPTY_LIST, new TypedByteArray("application/json", json.getBytes()));
}
Read also: Square retrofit server mock for testing
Hope it help