Latest changes for PHP 7.4 broke compatibility for PHP 8.1/8.2:
During inheritance of ArrayAccess: Uncaught Return type of SaintSystems\OData\Entity::offsetGet($offset) should either be compatible with ArrayAccess::offsetGet(mixed $offset): mixed, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice
This error occurs only when trying to subclass SaintSystems\OData\Entity that's why it was not caught by the unit tests.
Latest changes for PHP 7.4 broke compatibility for PHP 8.1/8.2:
During inheritance of ArrayAccess: Uncaught Return type of SaintSystems\OData\Entity::offsetGet($offset) should either be compatible with ArrayAccess::offsetGet(mixed $offset): mixed, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice
This error occurs only when trying to subclass
SaintSystems\OData\Entity
that's why it was not caught by the unit tests.