Description

Fixes #2659 by updating tests, that were verifying outdated semantic of except.

Previously provider.except(filter) wasn't recursive and was removing all the fallbacks.

Semantic of except was updated to solve the issues with using .except { it is ObjectValueProvider } on the following provider causing AbstractsObjectValueProvider and BuilderObjectValueProvider to be remoed (since they are fallbacks) and ObjectValueProvider itself not to be removed (since it's not on the top level, i.e. it's a part of ValueProvider.Combined that is nested into ValueProvider.Fallback that is nested into another ValueProvider.Combined).

ValueProvider.of(listOf(
    BooleanValueProvider,
    IntegerValueProvider,
    FloatValueProvider,
    StringValueProvider,
    NumberValueProvider,
    anyObjectValueProvider(idGenerator),
    ArrayValueProvider(idGenerator),
    EnumValueProvider(idGenerator),
    ListSetValueProvider(idGenerator),
    MapValueProvider(idGenerator),
    IteratorValueProvider(idGenerator),
    EmptyCollectionValueProvider(idGenerator),
    DateValueProvider(idGenerator),
    (ObjectValueProvider(idGenerator)
        with ArrayValueProvider(idGenerator)
        with EnumValueProvider(idGenerator)
        with ListSetValueProvider(idGenerator)
        with MapValueProvider(idGenerator)
        with IteratorValueProvider(idGenerator)
        with EmptyCollectionValueProvider(idGenerator)
        with DateValueProvider(idGenerator))
            .withFallback(
                AbstractsObjectValueProvider(idGenerator)
                        with BuilderObjectValueProvider(idGenerator)
            ),
    VoidValueProvider,
    NullValueProvider,
))

How to test

Automated tests

The proposed changes are verified with tests:
utbot-fuzzing/src/test/kotlin/org/utbot/fuzzing/ProvidersTest.kt

Self-check list

• I've set the proper labels for my PR (at least, for category and component).
• PR title and description are clear and intelligible.
• I've added enough comments to my code, particularly in hard-to-understand areas.
• The functionality I've repaired, changed or added is covered with automated tests.
• Manual tests have been provided optionally.
• The documentation for the functionality I've been working on is up-to-date.