@Test
    public void testGetCustomDefinition_withMappingReturningValue() {
        CustomDefinition value = Mockito.mock(CustomDefinition.class);
        Mockito.when(this.typesInGeneralConfigPart.getCustomDefinitionProviders())
                .thenReturn(Collections.singletonList((type, context) -> value));
        Assertions.assertSame(value, this.instance.getCustomDefinition(Mockito.mock(ResolvedType.class), this.getContext(), null));
    }
Test for the {@link SchemaGeneratorConfigImpl} class.
jsonschema-generator/src/test/java/com/github/victools/jsonschema/generator/impl/SchemaGeneratorConfigImplTest.java