### Question:
ConsumeTask extends AsyncTask<Purchase, Void, List<IabResult>> { @Override protected List<IabResult> doInBackground(final Purchase... purchases) { if (purchases == null || purchases.length == 0) throw new IllegalArgumentException("no purchases"); mPurchases = new ArrayList<Purchase>(purchases.length); Collections.addAll(mPurchases, purchases); final List<IabResult> results = new ArrayList<IabResult>(purchases.length); for (Purchase purchase : purchases) { try { mIabHelper.consume(purchase); results.add(new IabResult(OK, "Successful consume of sku " + purchase.getSku())); } catch (IabException ex) { results.add(ex.getResult()); } } return results; } ConsumeTask(IabHelper iabHelper,
                       OnConsumeFinishedListener singleListener,
                       OnConsumeMultiFinishedListener multiListener);   }### Answer:
@Test(expected = IllegalArgumentException.class) public void shouldVerifyArgumentsEmpty() throws Exception { task.doInBackground(); }
@Test(expected = IllegalArgumentException.class) public void shouldVerifyArgumentsNull() throws Exception { task.doInBackground((Purchase[]) null); }