MqttConnectTest demo code for higher order function as an argument

HighOrderDemoTest.kt

class HighOrderDemoTest {

    private lateinit var highOrderDemo: HighOrderDemo

    private var connectRemote: ConnectRemote = mockk(relaxed = true)

    @Before
    fun before() {
        highOrderDemo = HighOrderDemo(
            connectRemote
        )
    }

    @Test
    fun `test successful connection`() {
        
        every { connectRemote.connect(captureLambda<(isConnected: Boolean) -> Unit>()) } answers {
            lambda<(isConnected: Boolean) -> Unit>().captured.invoke(true)
        }
        
        highOrderDemo.connect {
            assertEquals(it, true)
        }
    }
}