Make `test_c_subclass_of_heap_ctype_with_tpdealloc_decrefs_once` and `test_c_subclass_of_heap_ctype_with_del_modifying_dunder_class_only_decrefs_once` behavioral tests

Feature or enhancement

Proposal:

The test_c_subclass_of_heap_ctype_with_tpdealloc_decrefs_once and test_c_subclass_of_heap_ctype_with_del_modifying_dunder_class_only_decrefs_once tests were added to verify that we don't decref a type object too many times when destroying an instance of the type in certain scenarios. The tests currently verify this by checking reference counts. This is sensitive to implementation details and likely to break in the future. To make this more robust, we'd like to refactor the tests and supporting C code to verify that we don't crash (a symptom of decrefing too many times).

Has this already been discussed elsewhere?

This is a minor feature, which does not need previous discussion elsewhere

Links to previous discussion of this feature:

No response

test_c_subclass_of_heap_ctype_with_tpdealloc_decrefs_once と test_c_subclass_of_heap_ctype_with_del_modifying_dunder_class_only_decrefs_once を検索し、その後、これらのテストで使用されている補助 C コードを調査します。テストと C のサポートコードをリファクタリングし、参照カウントを確認するのではなく、シナリオがクラッシュしないことを検証するようにします。影響を受けるテストを実行して、この動作を確認します。