How initialize binding in android test class?

Question

How initialize binding in test class? , I'm trying to write UI tests using espresso and I want to fetch views by binding.

@RunWith(AndroidJUnit4::class) class AuthFragmentTest{

private lateinit var scenario: FragmentScenario<AuthFragment>
private lateinit var binding: FragmentAuthBinding
private lateinit var usernameEditText: TextInputEditText
private lateinit var passwordEditText: TextInputEditText
private lateinit var submitButton: MaterialButton

@Before
fun setup(){
    scenario = launchFragmentInContainer(themeResId = R.style.Theme_Main)
    scenario.moveToState(Lifecycle.State.STARTED)
    binding
    usernameEditText = binding.usernameInputEditText
    passwordEditText = binding.passwordInputEditText
    submitButton = binding.uSubmit
}

@Test
fun testUserInput(){
    usernameEditText.setText("user")
    passwordEditText.setText("pass")
    Espresso.closeSoftKeyboard()
    val a = submitButton.isVisible
    Thread.sleep(10000)
    assertThat(a).isTrue()
}