integration-test.kt

private object TestObject : Serializable

@Test
fun `object instance is the same after deserialization`() {
    assertEquals(TestObject, serializeDeserialize(TestObject))
}

private fun serializeDeserialize(instance: Serializable): Serializable {
    val out = ByteArrayOutputStream()
    ObjectOutputStream(out).use {
        it.writeObject(instance)
    }
    return ObjectInputStream(ByteArrayInputStream(out.toByteArray())).use {
        it.readObject() as TestObject
    }
}