clone() method is on wrong interface

[gertjanschouten]

The Trigger interface extends Cloneable. However, the clone() method is specified on the MutableTrigger interface. This can sometimes lead to issues with mocking libraries such as mockk.

It would be better if the clone() method would be defined on Trigger, because that's the interface that extends Cloneable. Alternatively, the MutableTrigger interface should be the one extending Cloneable, instead of the Trigger interface. In any case, the clone() method should be on the interface that extends Cloneable, not on a subinterface.

[jhouserizer]

Hi! Although I agree that the class hierarchy is a bit wonky, it's a valid (legal) hierarchy, and has been that way for 15+ years. Changing in the hierarchy in a dot release is likely to cause problems for others (e.g. moving the clone method to Trigger would break third-party implementers of Trigger - which there are) .

(Note that the clone() method on MutableTrigger is changing the signature of clone, so that it doesn't throw a checked exception).