Robolectric ContentProvider测试

Question

我注意到,不时有一个关于使用Robolectric测试自定义ContentProviders的问题.但是,对于如何正确地做到这一点,从来没有一个具体而明确的答案.我偶然发现了两种不同的方法:

• 一个说你可以简单地实例化一个内存中的ContentProvider,你可以使用它来插入和查询数据(https://gist.github.com/anonymous/6139359)

• 另一个说使用ShadowContentResolver设置模拟光标数据(https://groups.google.com/d/msg/robolectric/r35mMirIkTs/xJJBNXl_RgwJ)

但是,我得到了两种方法的java.lang.InstantiationException.有一些SO帖子说这是由于SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java)没有在Robolectric中被覆盖(Android + Robolectric - 在ContentProvider中的queryBuilder.query()中的RuntimeException/InstantiationException).

我想我的问题是 - 是否有任何优先解决方法可以使测试ContentProviders成为可能.或者是否有任何其他方法比上面提到的那些更好.

Answer 1

这是Robolectric测试对我来说很好:

import android.content.ContentResolver;
import android.database.Cursor;
import android.net.Uri;

import org.joda.time.LocalDate;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.robolectric.Robolectric;
import org.robolectric.RobolectricTestRunner;
import org.robolectric.annotation.Config;
import org.robolectric.shadows.ShadowContentResolver;

import co.tomup.app.db.DbSchema;
import co.tomup.app.db.TomupContentProvider;
import co.tomup.app.db.model.CalendarDay;
import co.tomup.app.db.tables.CalendarDayTable;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;

@Config(emulateSdk = 18)
@RunWith(RobolectricTestRunner.class)
public class CalendarDayProviderTest {

    private ContentResolver mContentResolver;
    private ShadowContentResolver mShadowContentResolver;
    private TomupContentProvider mProvider;

    @Before
    public void setup() {
        mProvider = new TomupContentProvider();
        mContentResolver = Robolectric.application.getContentResolver();
        mShadowContentResolver = Robolectric.shadowOf(mContentResolver);
        mProvider.onCreate();
        ShadowContentResolver.registerProvider(DbSchema.AUTHORITY, mProvider);
    }

    @Test
    public void testInsertAndDelete() {
        // insert
        CalendarDay calendarDay = new CalendarDay();
        calendarDay.setId(1L);
        calendarDay.setDay(new LocalDate());
        calendarDay.setMoonPhase("new");
        calendarDay.setSunrise(1);
        calendarDay.setSunset(100);
        Uri insertionId = mContentResolver.insert(CalendarDayTable.CONTENT_URI,
                calendarDay.toSQLiteContentValues());
        Cursor cursorCheck = mShadowContentResolver.query(CalendarDayTable.CONTENT_URI,
                null, null, null, null);
        while (cursorCheck.moveToNext()) {
            CalendarDay calendarDayCheck = CalendarDay.fromSQLiteCursor(cursorCheck);
            assertEquals(calendarDay, calendarDayCheck);
        }
        assertTrue(cursorCheck.getCount() > 0);
        // delete
        mShadowContentResolver.delete(insertionId,
                null, null);
        cursorCheck = mShadowContentResolver.query(CalendarDayTable.CONTENT_URI,
                null, null, null, null);
        assertTrue(cursorCheck.getCount() == 0);
    }
}

Answer 2

您所要做的就是ShadowContentResolver在测试之前设置,因此它将正确地将您的权限ContentProvider与ContentProvider自身相关联.这是一个例子:

ShadowContentResolver.registerProvider(
        "com.example.provider",    //authority of your provider
        contentProvider    //instance of your ContentProvider (you can just use default constructor)    
);

最简单的方法是将这些东西放入一些带@Before注释的设置方法中.但是,更正确(因此长期更好)的方法是将其放入您的TestApplication#onCreate方法中,因此应用程序中的所有测试都将使用此配置.