android espresso测试用例输出说明

Question

我正在使用Espresso进行仪器测试。我想检查一下按钮是否显示了吐司。通过搜索，我得到了以下代码，检查吐司`

onView(withId(R.id.btnLogin))
                .perform(click())
                .inRoot(withDecorView(
                        not(mActivityRule.getActivity().
                                getWindow().getDecorView()))).
                check(matches(isDisplayed()));

. This is the output of when I run the test

$ adb shell am instrument -w -r   -e debug false -e class 'com.example.shantanub.mvpsample.LoginActivityTest#checkClick' com.example.shantanub.mvpsample.test/android.support.test.runner.AndroidJUnitRunner
Client not ready yet..
Started running tests
Tests ran to completion.

` 我应该如何解释此输出。测试成功。代码到底在做什么。