在Android Studio中，当我调试工具测试时，测试不会在任何断点处停止。调试单元测试可以正常工作。我有一个简单的工具测试，它只检查是否显示用户名edittext：

@RunWith(AndroidJUnit4.class)
public class LogonActivityTest {

    @Rule
    public ActivityTestRule<LogOnActivity> mActivityRule = new ActivityTestRule<>(LogOnActivity.class, true, false);

    @Before
    public void setUp() throws Exception {
        mActivityRule.launchActivity(new Intent()); // breakpoint here
    }

    @Test
    public void testSimple() throws Exception {
        onView(withId(R.id.act_logon_et_username)).check(matches(isDisplayed())); // breakpoint here
    }
}

在build.gradle中，我正确设置了

testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"

如何调试插桩测试？我使用Espresso，Mockito和Dagger2.