def _prev_index(self, s):
        self.set_index(max(0, self.index - 1))
def test_get_task_is_watcher(client):
    user = f.UserFactory.create()
    task = f.create_task(owner=user, milestone=None)
    f.MembershipFactory.create(project=task.project, user=user, is_admin=True)
    url_detail = reverse("tasks-detail", args=(task.id,))
    url_watch = reverse("tasks-watch", args=(task.id,))
    url_unwatch = reverse("tasks-unwatch", args=(task.id,))

    client.login(user)

    response = client.get(url_detail)
    assert response.status_code == 200
    assert response.data['watchers'] == []
    assert response.data['is_watcher'] == False

    response = client.post(url_watch)
    assert response.status_code == 200

    response = client.get(url_detail)
    assert response.status_code == 200
    assert response.data['watchers'] == [user.id]
    assert response.data['is_watcher'] == True

    response = client.post(url_unwatch)
    assert response.status_code == 200

    response = client.get(url_detail)
    assert response.status_code == 200
    assert response.data['watchers'] == []
    assert response.data['is_watcher'] == False