Any way to write unit tests for a custom editor?

Is there any good way to unit test a custom editor? For example, if I've got a custom editor that adds an item to a MonoBehavior's list, I have to make that addition via the editor's serializedObject, which is read-only, so it can't be assigned on the fly to an instance of the editor created within the test. Should I just give up trying to do this, or is there another way?