Testing JUnit in Android Studio with FirebaseAuth?

How to create unit tests with LoginPresenter FirebaseAuth

my LoginPresenter

public void loginUsingEmail(String email, String password) {
    if (TextUtils.isEmpty(email)) {
        view.showEmailError();
        return;
    }

    if (TextUtils.isEmpty(password)) {
        view.showPasswordError();
        return;
    }
    Log.v("loginUsingEmail","enter");
    auth.signInWithEmailAndPassword(email, password)
            .addOnCompleteListener(view, new OnCompleteListener<AuthResult>() {
                @Override
                public void onComplete(@NonNull Task<AuthResult> task) {
                    Log.v("enter auth","enter");
                    if (!task.isSuccessful())
                        view.loginFail(true);
                    else
                        view.loginSuccess();
                }
            });
}