func TestCanCountTheTweetsSentByAnUser(t *testing.T) {

    // Initialization
    service.InitializeService()

    var tweet, secondTweet, thirdTweet *domain.Tweet

    user := "grupoesfera"
    anotherUser := "nick"
    text := "This is my first tweet"
    secondText := "This is my second tweet"

    tweet = domain.NewTweet(user, text)
    secondTweet = domain.NewTweet(user, secondText)
    thirdTweet = domain.NewTweet(anotherUser, text)

    service.PublishTweet(tweet)
    service.PublishTweet(secondTweet)
    service.PublishTweet(thirdTweet)

    // Operation
    count := service.CountTweetsByUser(user)

    // Validation
    if count != 2 {
        t.Errorf("Expected count is 2 but was %d", count)
    }

}