==========
Test Utils
==========

.. module:: djem.utils.tests


``setup_test_app()``
====================

.. versionadded:: 0.7

.. autofunction:: setup_test_app

    This solution is adapted from Simon Charette's `comment on Django ticket #7835 <https://code.djangoproject.com/ticket/7835#comment:46>`_.


``MessagingRequestFactory``
===========================

.. versionadded:: 0.6

.. class:: MessagingRequestFactory

    An extension of Django's ``RequestFactory`` `helper for tests <https://docs.djangoproject.com/en/stable/topics/testing/advanced/#the-request-factory>`_ that enables the use of the messages framework within the generated request. It does not use the standard message storage backend (as per the ``MESSAGE_STORAGE`` setting), but rather a memory-only backend that does not involve the use of sessions, cookies or any other means of persistent storage of the messages. Thus, messages need to be read in the same request they were added, or they will be lost.

    It is used in the same way as ``RequestFactory``:

    .. code-block:: python

        from django.contrib.auth.models import User
        from django.contrib import messages
        from django.test import TestCase

        from djem.utils.tests import MessagingRequestFactory

        # Views expected to set messages
        from .views import MyView, my_view


        class SimpleTest(TestCase):

            def setUp(self):

                self.factory = MessagingRequestFactory()
                self.user = User.objects.create_user(
                    username='test.user', email='test@…', password='top_secret'
                )

            def test_details(self):

                request = self.factory.get('/customer/details')

                # Recall that middleware are not supported. You can simulate a
                # logged-in user by setting request.user manually.
                request.user = self.user

                # Test my_view() as if it were deployed at /customer/details
                response = my_view(request)

                # Use this syntax for class-based views
                response = MyView.as_view()(request)

                self.assertEqual(response.status_code, 200)

                # Test the expected message was set
                message_list = list(messages.get_messages(request))
                self.assertEqual(len(message_list), 1)
                self.assertEqual(message_list[0].message, 'An error occurred.')


``TemplateRendererMixin``
=========================

.. versionadded:: 0.6

.. class:: TemplateRendererMixin

    A mixin for ``TestCase`` classes whose tests render templates from strings (as opposed to rendering them from files), using the Django template engine.

    .. automethod:: render_template

    .. code-block:: python

        from django.contrib.auth.models import User
        from django.test import TestCase

        from djem.utils.tests import TemplateRendererMixin


        class SomeTestCase(TemplateRendererMixin, TestCase):

            def setUp(self):

                self.user = self.user = User.objects.create_user(
                    username='test.user', email='test@…', password='top_secret'
                )

            def test_something(self):

                template_string = (
                    '{% if something %}'
                    '    <p>'
                    '        The user is: {{ user.username }}'
                    '    </p>'
                    '{% endif %}'
                )

                output = self.render_template(template_string, {
                    'something': True
                })

                self.assertEqual(output, '<p> The user is: test.user </p>')