android - Espresso 测试时如何从 Asset 文件夹中读取 json 文件？

Question

我正在尝试基于 .json 文件创建一些假对象。所以我的项目的架构是这样的:

- MyProject
- app
---- src
-------- androidTest
------------ assets
---------------- FirstObject.json
---------------- SecondObject.json
------------ java
-------- main
-------- test

我正在使用 Espresso 进行测试，并且在 assets 文件夹下有一些 .json 文件。

我的测试类是这样的:

@RunWith(AndroidJUnit4.class)
public class LocatingActivityTest
{
    @Rule
    public ActivityTestRule<BookingActivity> mActivityTestRule = new ActivityTestRule<>(BookingActivity.class);

    private BookingActivity mBookingActivity;

    @Before
    public void setup()
    {
        mBookingActivity = mActivityTestRule.getActivity();
    }

    @Test
    public void viewsMustBeVisible()
    {
        onView(withId(R.id.fab_booking)).perform(click());
        onView(withId(R.id.booking_book_now)).check(matches(not(isEnabled())));

        mBookingActivity.setTestBooking(BookingTest.getStandardFlight(),
                MyServiceProvider.getServices1(mBookingActivity), // <= Problem
                true,
                MyServiceProvider.getServices2(mBookingActivity), // <= Problem
                MyServiceProvider.getServices3(mBookingActivity)); // <= Problem

        onView(withId(R.id.booking_book_now)).check(matches(isEnabled()));
        onView(withId(R.id.booking_book_now)).perform(click());

        onView(withId(R.id.text)).check(matches(isCompletelyDisplayed()));
        onView(withId(R.id.sonarView)).check(matches(isCompletelyDisplayed()));
        onView(withId(R.id.cancel_booking)).check(matches(isCompletelyDisplayed()));
    }
}

问题出在我的 MyServiceProvider 类中:

public final class MyServiceProvider
{
    public static List<FlightType> getServices1(Context context)
    {
        try
        {
            InputStream inputStream = context.getAssets().open("FlightTypes.json");
            String jsonString = read(inputStream);
            Log.e("XXX", "getServices1() => " + jsonString);
            Type listType = new TypeToken<List<FlightType>>(){}.getType();
            List<FlightType> flightTypeList = new Gson().fromJson(jsonString, listType);

            return flightTypeList;
        }
        catch (IOException e)
        {
            e.printStackTrace();
        }

        return null;
    }

    private static String read(InputStream inputStream) throws IOException
    {
        StringWriter writer = new StringWriter();
        IOUtils.copy(inputStream, writer, "UTF-8");
        return writer.toString();
    }
.
.
.
}

由于某些原因 InputStream inputStream = context.getAssets().open("FlightTypes.json"); 无法打开 json 文件并抛出异常。这是我的日志:

02-17 21:00:58.984 5686-5706/com.xxx.xxx W/System.err: java.io.FileNotFoundException: FlightTypes.json
02-17 21:00:58.984 5686-5706/com.xxx.xxx W/System.err:     at android.content.res.AssetManager.openAsset(Native Method)
02-17 21:00:58.984 5686-5706/com.xxx.xxx W/System.err:     at android.content.res.AssetManager.open(AssetManager.java:313)
02-17 21:00:58.984 5686-5706/com.xxx.xxx W/System.err:     at android.content.res.AssetManager.open(AssetManager.java:287)
02-17 21:00:58.984 5686-5706/com.xxx.xxx W/System.err:     at com.xxx.xxx.utility.MyServiceProvider.getServices1(MyServiceProvider.java:31)

Answer 1

不要将 Activity 作为上下文传递。而是传递 InstrumentationRegistry.getContext() 看看是否有帮助。