与这个问题有点关联，但我在寻求帮助时来到了这里。可能对一些人有帮助。如果你用RenamingDelegatingContext初始化你的数据库，它会在运行之间清理数据库。

public class DataManagerTest extends InstrumentationTestCase {

  private DataManager subject;

  @Before
  public void setUp() {
    super.setUp();

    RenamingDelegatingContext newContext = new RenamingDelegatingContext(getInstrumentation().getContext(), "test_");
    subject = new DataManager(newContext);
  }

  // tests...
}

和关联的数据管理器类。

public class DataManager {

    private SQLiteDatabase mDatabase;
    private SQLiteOpenHelper mHelper;
    private final String mDatabaseName = "table";
    private final int mDatabaseVersion = 1;

    protected DataManager(Context context) {
    this.mContext = context;
    createHelper();
  }

  private void createHelper() {
    mHelper = new SQLiteOpenHelper(mContext, mDatabaseName, null, mDatabaseVersion) {
      @Override
      public void onCreate(SQLiteDatabase sqLiteDatabase) {
        // createTable...
      }

      @Override
      public void onUpgrade(SQLiteDatabase sqLiteDatabase, int oldVersion, int newVersion) {
        // upgrade table
      }
    };
  }
    ...
}

mDb.delete(DATABASE_TABLE_NAME, null, null);

这确实是解决办法/可行之道...
我将setUp（..）方法中的第一行更改为：

cleanUpDatabase(tableList);

然后我添加了方法cleanUpDatabasese（..），类似于：

private void cleanUpDatabase(List<String> dbTables) {
    Log.i(LOG_TAG, "Preparing to clean up database...");
    DatabaseHelper dbHelper = new DatabaseHelper(getInstrumentation().getTargetContext());
    ConnectionSource cs = dbHelper.getConnectionSource();
    SQLiteDatabase db = dbHelper.getWritableDatabase();

    Log.i(LOG_TAG, "Dropping all tables");
    for (String table : dbTables) {
        db.execSQL("DROP TABLE IF EXISTS " + table);
    }

    Log.i(LOG_TAG, "Executing the onCreate(..)");
    dbHelper.onCreate(db, cs);

    Log.i(LOG_TAG, "Verifying the data...");
    for (String table : dbTables) {
        Cursor c = db.query(table, new String[]{"id"}, null, null, null, null, null);
        int count = c.getCount();
        if (count != 1 && (table.equals("project") || table.equals("task"))) {
            dbHelper.close();
            Log.e(LOG_TAG, "We should have 1 record for table " + table + " after cleanup but we found " + count + " record(s)");
            throw new RuntimeException("Error during cleanup of DB, exactly one record should be present for table " + table + " but we found " + count + " record(s)");
        } else if (count != 0 && !(table.equals("project") || table.equals("task"))) {
            dbHelper.close();
            Log.e(LOG_TAG, "We should have 0 records for table " + table + " after cleanup but we found " + count + " record(s)");
            throw new RuntimeException("Error during cleanup of DB, no records should be present for table " + table + " but we found " + count + " record(s)");
        }
    }

    Log.i(LOG_TAG, "The database has been cleaned!");
    dbHelper.close();
}

这段代码在每个测试之前执行，这使得我的所有测试彼此独立。

警告：为了检索对您的DatabaseHelper的引用（您自己的实现偏离了轨道;））您不能调用getActivity()，因为这将启动您的活动（并因此执行所有初始DB加载（如果有..）

仪器注册表→获取上下文→删除数据库

android.support.test.InstrumentationRegistry的getTargetContext和可能与直觉相反的getContext应该可以实现这个功能：

概要

使用 * getContext * 删除数据库（不是*getTargetContext *）。
getContext().deleteDatabase(DbHelper.DATABASE_NAME);

示例

public class DbHelperTest {
private DbHelper mDb;

    @Before
    public void setUp() throws Exception {
        getContext().deleteDatabase(DbHelper.DATABASE_NAME);
        mDb = new DbHelper(getTargetContext());
    }

    @After
    public void tearDown() throws Exception {
        mDb.close();
    }

    @Test
    public void onCreate() throws Exception {
        mDb.onCreate(mDb.getWritableDatabase());
    }

    @Test
    public void onUpgrade() throws Exception {
        mDb.onUpgrade(mDb.getWritableDatabase(), 1, 2);
    }

    @Test
    public void dropTable() throws Exception {
        String tableName = "mesa";
        mDb.getReadableDatabase().execSQL("CREATE TABLE "
            + tableName + "(_id INTEGER PRIMARY KEY AUTOINCREMENT)");
        mDb.dropTable(mDb.getWritableDatabase(), tableName);
    }
}

您尝试开始时间所有表数据删除更改本机解决方案。

mDb.delete(DATABASE_TABLE_NAME, null, null);

由于我的数据库是加密的，我需要在每个测试用例后删除实际的数据库文件。我在从RenamingDelegatingContext创建deleteDatabase时遇到了麻烦，因为RenamingDelegatingContext由于某种原因找不到以前创建的数据库。
AndroidTestCase子类的解决方案：

@Override
protected void setUp() throws Exception {
    super.setUp();
    mContext = new RenamingDelegatingContext(getContext(), TEST_DB_PREFIX);

   // create db here
}

@Override
protected void tearDown() throws Exception {
    // Making RenamingDelegatingContext find the test database
    ((RenamingDelegatingContext) mContext).makeExistingFilesAndDbsAccessible();
     mContext.deleteDatabase(DB_NAME);

    super.tearDown();
}

在每次测试运行它之前

val context: Context = ApplicationProvider.getApplicationContext()
context.deleteDatabase("myDatabaseName.db")

这也可以作为一个规则