Support for @Mock fields in JUnit5's @Nested classes

[sinhote]

• Version of JMockit that was used: 1.41

• Description of the problem or enhancement request:

I've seen that if one uses a @Nested class containing fields annotated with @Mocked, those are not initialized (resulting in NPEs).

An obvious workaround is to move those fields to the outer class, but this somewhat goes against the spirit of nested classes, which allow to encapsulate related groups of tests. If the mocked fields are only relevant to the nested class, why should they be defined outside?

I've seen this was already reported in #458, but it was closed by simply saying "only fields in outer classes are supported by @Mock". Can this be reconsidered?

Here's a sample code demonstrating the issue:

class MockedNestedTest {
    @Nested
    class Field {
        @Mocked Foo foo;
        @Test
        void shouldInitializeField() {
            Assertions.assertNotNull(foo); // this fails
        }
    }

Thanks!