Testing guidelines

Testing Best Practices

Parceling

Since we need to maintain compatibility with respect to variances in CMSDK vs CM Framework versions, and we can't rely on runtime stubs like AOSP, we've adopted a "header" for any parcels which are sent over IPC. This header is fairly straightforward and is generously borrowed from the implementation in DashClock.

Since we rely so heavily on making sure that custom objects can pass over IPC correctly, our testing paradigms needs to enforce this.

A quick example is shown (from):

@SmallTest
public void testCustomTileOnSettingsClickIntentUnravelFromParcel() {
    Intent intent = new Intent(mContext, DummySettings.class);
    CustomTile expectedCustomTile = new CustomTile.Builder(mContext)
        .setOnSettingsClickIntent(intent)
        .build();

    // Write to parcel
    Parcel parcel = Parcel.obtain();
    expectedCustomTile.writeToParcel(parcel, 0);

    // Rewind
    parcel.setDataPosition(0);

    // Verify data when unraveling
    CustomTile fromParcel = CustomTile.CREATOR.createFromParcel(parcel);

    assertNotNull(fromParcel.onSettingsClick);
    assertEquals(expectedCustomTile.onSettingsClick.toString(),
            fromParcel.onSettingsClick.toString());
}

As you can see, we populate the members we want to test when sending over IPC. Instead of directly sending the parcel over IPC, and mocking out way too many things, we cheat a bit. Take the custom object, write it to a parcel, rewind the parcel to its original data position and leverage the custom objects CREATOR to recreate a new Object for comparison.

Common Builder Pattern

The common builder pattern is tested mostly the same way (we're essentially just testing that the builders .build() invocation actually gives us the data we want.

@SmallTest
public void testCustomTileBuilderOnClickIntent() {
    Intent intent = new Intent(Intent.ACTION_DIAL);
    PendingIntent pendingIntent = PendingIntent.getActivity(mContext, 0, intent, 0);
    CustomTile customTile = new CustomTile.Builder(mContext)
        .setOnClickIntent(pendingIntent)
        .build();
    assertNotNull(customTile.onClick);
    assertEquals(pendingIntent, customTile.onClick);
}

The above assertion simply tests that the pending intent we're passing in actually comes out of the built custom tile object as expected.