If you end up mocking every non-private method of a class in order to write tests, it is a strong sign that your test became too complex, or that
you misunderstood the way you are supposed to use the mocking mechanism.
You should either refactor the test code into multiple units, or consider using the class itself, by either directly instantiating it, or creating
a new one inheriting from it, with the expected behavior.
This rule reports an issue when every member of a given class are mocked.
Noncompliant code example
@Test
void test_requiring_MyClass() {
MyClass myClassMock = mock(MyClass.class); // Noncompliant
when(myClassMock.f()).thenReturn(1);
when(myClassMock.g()).thenReturn(2);
//...
}
abstract class MyClass {
abstract int f();
abstract int g();
}
Compliant solution
@Test
void test_requiring_MyClass() {
MyClass myClass = new MyClassForTest();
//...
}
class MyClassForTest extends MyClass {
@Override
int f() {
return 1;
}
@Override
int g() {
return 2;
}
}
or
@Test
void test_requiring_f() {
MyClass myClassMock = mock(MyClass.class);
when(myClassMock.f()).thenReturn(1);
//...
}
@Test
void test_requiring_g() {
MyClass myClassMock = mock(MyClass.class);
when(myClassMock.g()).thenReturn(2);
//...
}
abstract class MyClass {
abstract int f();
abstract int g();
}
