mozilla/nunjucks-docs — pull request #16 by christiangenco (2014-10-13 06:48:58+00:00)
Title: "hasn't been problems".tr("hasn't", "haven't")

{% block grammarNazi %}
If there were problems, you would say "There *have* been problems," not "there *has* been problems." The subject, "problems," is plural, so you use "have," and therefore "haven't."
{% endblock %}