Robolectric and IntentServices

Using Robolectric, how would one go about testing an IntentService that broadcasts intents as a response?

Assuming the following class:

class MyService extends IntentService {
    @Override
    protected void onHandleIntent(Intent intent) {
        LocalBroadcastManager.getInstance(this).sendBroadcast(new Intent("action"));
    }
}

In my test case, I'm attempting to do something like this:

@RunWith(RobolectricTestRunner.class)
public class MyServiceTest{
    @Test
    public void testPurchaseHappyPath() throws Exception {

        Context context = new Activity();

        // register broadcast receiver
        BroadcastReceiver br = new BroadcastReceiver() {

            @Override
            public void onReceive(Context context, Intent intent) {
                // test logic to ensure that this is called
            }

        };
        context.registerReceiver(br, new IntentFilter("action"));

        // This doesn't work
        context.startService(new Intent(context, MyService.class));

    }

}

MyService is never started using this approach. I'm relatively new to Robolectric, so I'm probably missing something obvious. Is there some sort of binding I have to do before calling startService? I've verified that broadcasting works by just calling sendBroadcast on the context. Any ideas?