@Test
  public void testOmitNullableWithBuilder() {
    NullablePropertyWithBuilder instance1 =
        NullablePropertyWithBuilder.builder().notNullable("hello").build();
    assertThat(instance1.notNullable()).isEqualTo("hello");
    assertThat(instance1.nullable()).isNull();

    NullablePropertyWithBuilder instance2 =
        NullablePropertyWithBuilder.builder().notNullable("hello").nullable(null).build();
    assertThat(instance2.notNullable()).isEqualTo("hello");
    assertThat(instance2.nullable()).isNull();
    assertThat(instance1).isEqualTo(instance2);

    NullablePropertyWithBuilder instance3 =
        NullablePropertyWithBuilder.builder().notNullable("hello").nullable("world").build();
    assertThat(instance3.notNullable()).isEqualTo("hello");
    assertThat(instance3.nullable()).isEqualTo("world");

    IllegalStateException e =
        assertThrows(
            IllegalStateException.class, () -> NullablePropertyWithBuilder.builder().build());
    assertThat(e).hasMessageThat().contains("notNullable");

    NullablePropertyWithBuilder.Builder builder = NullablePropertyWithBuilder.builder();
    Truth.assertThat(builder.nullable()).isEmpty();
  }
Returns a set containing this test's {@link Nullable @Nullable} annotation, plus possibly
another {@code @Nullable} that is present on the parameter of {@link Object#equals}.
value/src/it/functional/src/test/java/com/google/auto/value/AutoValueJava8Test.java