class PrimaryKeyString : RealmObject {
    @PrimaryKey
    var primaryKey: String = Random.nextULong().toString()
}

realm.writeBlocking {
    val first = copyToRealm(PrimaryKeyString().apply { primaryKey = PRIMARY_KEY })
    val second = copyToRealm(PrimaryKeyString().apply { primaryKey = "Other key" })
    
    // expect update to cause an error
    assertFailsWith<RuntimeException> { 
        second.primaryKey = PRIMARY_KEY
    }
    
    // eliminating the above assert will render the following to pass, which shows that we end up with two objects both with the same primary key value
    val objects = objects(PrimaryKeyString::class)
    assertEquals(2, objects.size)
    val first2 = objects[0]
    val second2 = objects[1]
    assertEquals(objects[0].primaryKey, objects[1].primaryKey)
}