Implementation methods inherited from `kotlin-stdlib` `Abstract[x]` are not visible in interfaces

[Lordfirespeed]

For example, PersistentList. The interface declaration:

public interface ImmutableList<out E> : List<E>, ImmutableCollection<E> { /* ... */ }
public interface PersistentList<out E> : ImmutableList<E>, PersistentCollection<E> { /* ... */ }

reasonably claims it implements the List interface.

The base implementation declaration:

abstract class AbstractPersistentList<E> : PersistentList<E>, AbstractList<E>() { /* ... */ }

inherits stdlib's AbstractList, which contains methods not present in the List interface, such as

• fun equals(other: Any?): Boolean
• fun hashCode(): Int

Which means that following the declaration of a PersistentList's hashCode function, for example, will go to Any#hashCode, which is misleading.

val myPersistentList: PersistentList<T> = persistentListOf(1,2,3)
myPersistentList.hashCode() // go to declaration -> `Any#hashCode`. Should be `AbstractList#hashCode`

[Lordfirespeed]

Truthfully, the same issue is apparent with stdlib builtins such as listOf, so perhaps this is more of a them problem. :joy:

[qurbonzoda]

Hi, Because PersistentList is an interface and does not provide hashCode implementation, navigating to the function leads to the Any.hashCode(). This is an expected behavior of the IntelliJ IDEA.