/**
  * マイナスしてからプラスする。
  *
  * <p>最初のマイナスは取り消されて、プラスだけが残る
  *
  * @author shin1ogawa
  */
 @Test
 public void minusAndPlus() {
   int beforePlusCount = tester.count(Plus.class);
   int beforeMinusCount = tester.count(Minus.class);
   PlusAndMinusService.minus(account.getKey(), discussions.get(0).getKey());
   PlusAndMinusService.plus(account.getKey(), discussions.get(0).getKey());
   int afterPlusCount = tester.count(Plus.class);
   int afterMinusCount = tester.count(Minus.class);
   assertThat(afterPlusCount, is(beforePlusCount + 1));
   assertThat(afterMinusCount, is(beforeMinusCount));
 }
  @Override
  public void setUp() throws Exception {
    super.setUp();
    account = new Account();
    account.setKey(Datastore.createKey(Account.class, 1));
    Datastore.put(account);

    discussions = new ArrayList<Submission>();
    for (int i = 0; i < 10; i++) {
      Submission submission = new Submission();
      submission.setTitle("title" + i);
      submission.setDescription("description" + i);
      submission.setAuthor(Datastore.createKey(Account.class, i + 1));
      submission.setAuthorName("author" + i);
      discussions.add(submission);
    }
    Datastore.put(discussions);
  }