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+.. _topics-testing:
+
+===========================
+Testing Django applications
+===========================
+
+.. module:: django.test
+   :synopsis: Testing tools for Django applications.
+
+Automated testing is an extremely useful bug-killing tool for the modern
+Web developer. You can use a collection of tests -- a **test suite** -- to
+solve, or avoid, a number of problems:
+
+    * When you're writing new code, you can use tests to validate your code
+      works as expected.
+
+    * When you're refactoring or modifying old code, you can use tests to
+      ensure your changes haven't affected your application's behavior
+      unexpectedly.
+
+Testing a Web application is a complex task, because a Web application is made
+of several layers of logic -- from HTTP-level request handling, to form
+validation and processing, to template rendering. With Django's test-execution
+framework and assorted utilities, you can simulate requests, insert test data,
+inspect your application's output and generally verify your code is doing what
+it should be doing.
+
+The best part is, it's really easy.
+
+This document is split into two primary sections. First, we explain how to
+write tests with Django. Then, we explain how to run them.
+
+Writing tests
+=============
+
+There are two primary ways to write tests with Django, corresponding to the
+two test frameworks that ship in the Python standard library. The two
+frameworks are:
+
+    * **Doctests** -- tests that are embedded in your functions' docstrings and
+      are written in a way that emulates a session of the Python interactive
+      interpreter. For example::
+
+          def my_func(a_list, idx):
+              """
+              >>> a = ['larry', 'curly', 'moe']
+              >>> my_func(a, 0)
+              'larry'
+              >>> my_func(a, 1)
+              'curly'
+              """
+              return a_list[idx]
+
+    * **Unit tests** -- tests that are expressed as methods on a Python class
+      that subclasses ``unittest.TestCase``. For example::
+
+          import unittest
+
+          class MyFuncTestCase(unittest.TestCase):
+              def testBasic(self):
+                  a = ['larry', 'curly', 'moe']
+                  self.assertEquals(my_func(a, 0), 'larry')
+                  self.assertEquals(my_func(a, 1), 'curly')
+
+You can choose the test framework you like, depending on which syntax you
+prefer, or you can mix and match, using one framework for some of your code and
+the other framework for other code. You can also use any *other* Python test
+frameworks, as we'll explain in a bit.
+
+Writing doctests
+----------------
+
+Doctests use Python's standard doctest_ module, which searches your docstrings
+for statements that resemble a session of the Python interactive interpreter.
+A full explanation of how doctest works is out of the scope of this document;
+read Python's official documentation for the details.
+
+.. admonition:: What's a **docstring**?
+
+    A good explanation of docstrings (and some guidelines for using them
+    effectively) can be found in :pep:`257`:
+
+        A docstring is a string literal that occurs as the first statement in
+        a module, function, class, or method definition.  Such a docstring
+        becomes the ``__doc__`` special attribute of that object.
+
+    For example, this function has a docstring that describes what it does::
+
+        def add_two(num):
+          "Return the result of adding two to the provided number."
+           return num + 2
+
+    Because tests often make great documentation, putting tests directly in
+    your docstrings is an effective way to document *and* test your code.
+
+For a given Django application, the test runner looks for doctests in two
+places:
+
+    * The ``models.py`` file. You can define module-level doctests and/or a
+      doctest for individual models. It's common practice to put
+      application-level doctests in the module docstring and model-level
+      doctests in the model docstrings.
+
+    * A file called ``tests.py`` in the application directory -- i.e., the
+      directory that holds ``models.py``. This file is a hook for any and all
+      doctests you want to write that aren't necessarily related to models.
+
+Here is an example model doctest::
+
+    # models.py
+
+    from django.db import models
+
+    class Animal(models.Model):
+        """
+        An animal that knows how to make noise
+
+        # Create some animals
+        >>> lion = Animal.objects.create(name="lion", sound="roar")
+        >>> cat = Animal.objects.create(name="cat", sound="meow")
+
+        # Make 'em speak
+        >>> lion.speak()
+        'The lion says "roar"'
+        >>> cat.speak()
+        'The cat says "meow"'
+        """
+        name = models.CharField(max_length=20)
+        sound = models.CharField(max_length=20)
+
+        def speak(self):
+            return 'The %s says "%s"' % (self.name, self.sound)
+
+When you :ref:`run your tests <running-tests>`, the test runner will find this docstring, notice
+that portions of it look like an interactive Python session, and execute those
+lines while checking that the results match.
+
+In the case of model tests, note that the test runner takes care of
+creating its own test database. That is, any test that accesses a
+database -- by creating and saving model instances, for example --
+will not affect your production database. Each doctest begins with a
+"blank slate" -- a fresh database containing an empty table for each
+model. (See the section on fixtures, below, for more on this.) Note
+that to use this feature, the database user Django is connecting as
+must have ``CREATE DATABASE`` rights.
+
+For more details about how doctest works, see the `standard library
+documentation for doctest`_
+
+.. _doctest: http://docs.python.org/lib/module-doctest.html
+.. _standard library documentation for doctest: doctest_
+
+Writing unit tests
+------------------
+
+Like doctests, Django's unit tests use a standard library module: unittest_.
+This module uses a different way of defining tests, taking a class-based
+approach.
+
+As with doctests, for a given Django application, the test runner looks for
+unit tests in two places:
+
+    * The ``models.py`` file. The test runner looks for any subclass of
+      ``unittest.TestCase`` in this module.
+
+    * A file called ``tests.py`` in the application directory -- i.e., the
+      directory that holds ``models.py``. Again, the test runner looks for any
+      subclass of ``unittest.TestCase`` in this module.
+
+This example ``unittest.TestCase`` subclass is equivalent to the example given
+in the doctest section above::
+
+    import unittest
+    from myapp.models import Animal
+
+    class AnimalTestCase(unittest.TestCase):
+        def setUp(self):
+            self.lion = Animal.objects.create(name="lion", sound="roar")
+            self.cat = Animal.objects.create(name="cat", sound="meow")
+
+        def testSpeaking(self):
+            self.assertEquals(self.lion.speak(), 'The lion says "roar"')
+            self.assertEquals(self.cat.speak(), 'The cat says "meow"')
+
+When you :ref:`run your tests <running-tests>`, the default behavior of the test utility is
+to find all the test cases (that is, subclasses of ``unittest.TestCase``)
+in ``models.py`` and ``tests.py``, automatically build a test suite out of
+those test cases, and run that suite.
+
+In the Django development version, there is a second way to define the test
+suite for a module: if you define a function called ``suite()`` in either
+``models.py`` or ``tests.py``, the Django test runner will use that function
+to construct the test suite for that module. This follows the
+`suggested organization`_ for unit tests. See the Python documentation for
+more details on how to construct a complex test suite.
+
+For more details about ``unittest``, see the `standard library unittest
+documentation`_.
+
+.. _unittest: http://docs.python.org/lib/module-unittest.html
+.. _standard library unittest documentation: unittest_
+.. _suggested organization: http://docs.python.org/lib/organizing-tests.html
+
+Which should I use?
+-------------------
+
+Because Django supports both of the standard Python test frameworks, it's up to
+you and your tastes to decide which one to use. You can even decide to use
+*both*.
+
+For developers new to testing, however, this choice can seem confusing. Here,
+then, are a few key differences to help you decide which approach is right for
+you:
+
+    * If you've been using Python for a while, ``doctest`` will probably feel
+      more "pythonic". It's designed to make writing tests as easy as possible,
+      so it requires no overhead of writing classes or methods. You simply put
+      tests in docstrings. This has the added advantage of serving as
+      documentation (and correct documentation, at that!).
+
+      If you're just getting started with testing, using doctests will probably
+      get you started faster.
+
+    * The ``unittest`` framework will probably feel very familiar to developers
+      coming from Java. ``unittest`` is inspired by Java's JUnit, so you'll
+      feel at home with this method if you've used JUnit or any test framework
+      inspired by JUnit.
+
+    * If you need to write a bunch of tests that share similar code, then
+      you'll appreciate the ``unittest`` framework's organization around
+      classes and methods. This makes it easy to abstract common tasks into
+      common methods. The framework also supports explicit setup and/or cleanup
+      routines, which give you a high level of control over the environment
+      in which your test cases are run.
+
+Again, remember that you can use both systems side-by-side (even in the same
+app). In the end, most projects will eventually end up using both. Each shines
+in different circumstances.
+
+.. _running-tests:
+
+Running tests
+=============
+
+Once you've written tests, run them using your project's ``manage.py`` utility::
+
+    $ ./manage.py test
+
+By default, this will run every test in every application in
+:setting:`INSTALLED_APPS`. If you only want to run tests for a particular
+application, add the application name to the command line. For example, if your
+:setting:`INSTALLED_APPS` contains ``'myproject.polls'`` and
+``'myproject.animals'``, you can run the ``myproject.animals`` unit tests alone
+with this command::
+
+    # ./manage.py test animals
+
+Note that we used ``animals``, not ``myproject.animals``.
+
+**New in Django development version:** If you use unit tests, as opposed to
+doctests, you can be even *more* specific in choosing which tests to execute.
+To run a single test case in an application (for example, the
+``AnimalTestCase`` described in the "Writing unit tests" section), add the
+name of the test case to the label on the command line::
+
+    $ ./manage.py test animals.AnimalTestCase
+
+And it gets even more granular than that! To run a *single* test method inside
+a test case, add the name of the test method to the label::
+
+    $ ./manage.py test animals.AnimalTestCase.testFluffyAnimals
+
+The test database
+-----------------
+
+Tests that require a database (namely, model tests) will not use
+your "real" (production) database. A separate, blank database is created
+for the tests.
+
+Regardless of whether the tests pass or fail, the test database is destroyed
+when all the tests have been executed.
+
+By default this test database gets its name by prepending ``test_`` to the value
+of the :setting:`DATABASE_NAME` setting. When using the SQLite database engine
+the tests will by default use an in-memory database (i.e., the database will be
+created in memory, bypassing the filesystem entirely!). If you want to use a
+different database name, specify the :setting:`TEST_DATABASE_NAME` setting.
+
+Aside from using a separate database, the test runner will otherwise use all of
+the same database settings you have in your settings file:
+:setting:`DATABASE_ENGINE`, :setting:`DATABASE_USER`, :setting:`DATABASE_HOST`,
+etc. The test database is created by the user specified by
+:setting:`DATABASE_USER`, so you'll need to make sure that the given user
+account has sufficient privileges to create a new database on the system.
+
+**New in Django development version:** For fine-grained control over the
+character encoding of your test database, use the
+:setting:`TEST_DATABASE_CHARSET` setting. If you're using MySQL, you can also
+use the :setting:`TEST_DATABASE_COLLATION` setting to control the particular
+collation used by the test database. See the :ref:`settings documentation
+<ref-settings>` for details of these advanced settings.
+
+Understanding the test output
+-----------------------------
+
+When you run your tests, you'll see a number of messages as the test runner
+prepares itself. You can control the level of detail of these messages with the
+``verbosity`` option on the command line::
+
+    Creating test database...
+    Creating table myapp_animal
+    Creating table myapp_mineral
+    Loading 'initial_data' fixtures...
+    No fixtures found.
+
+This tells you that the test runner is creating a test database, as described
+in the previous section.
+
+Once the test database has been created, Django will run your tests.
+If everything goes well, you'll see something like this::
+
+    ----------------------------------------------------------------------
+    Ran 22 tests in 0.221s
+
+    OK
+
+If there are test failures, however, you'll see full details about which tests
+failed::
+
+    ======================================================================
+    FAIL: Doctest: ellington.core.throttle.models
+    ----------------------------------------------------------------------
+    Traceback (most recent call last):
+      File "/dev/django/test/doctest.py", line 2153, in runTest
+        raise self.failureException(self.format_failure(new.getvalue()))
+    AssertionError: Failed doctest test for myapp.models
+      File "/dev/myapp/models.py", line 0, in models
+
+    ----------------------------------------------------------------------
+    File "/dev/myapp/models.py", line 14, in myapp.models
+    Failed example:
+        throttle.check("actor A", "action one", limit=2, hours=1)
+    Expected:
+        True
+    Got:
+        False
+
+    ----------------------------------------------------------------------
+    Ran 2 tests in 0.048s
+
+    FAILED (failures=1)
+
+A full explanation of this error output is beyond the scope of this document,
+but it's pretty intuitive. You can consult the documentation of Python's
+``unittest`` library for details.
+
+Note that the return code for the test-runner script is the total number of
+failed and erroneous tests. If all the tests pass, the return code is 0. This
+feature is useful if you're using the test-runner script in a shell script and
+need to test for success or failure at that level.
+
+Testing tools
+=============
+
+Django provides a small set of tools that come in handy when writing tests.
+
+The test client
+---------------
+
+.. module:: django.test.client
+   :synopsis: Django's test client.
+
+The test client is a Python class that acts as a dummy Web browser, allowing
+you to test your views and interact with your Django-powered application
+programmatically.
+
+Some of the things you can do with the test client are:
+
+    * Simulate GET and POST requests on a URL and observe the response --
+      everything from low-level HTTP (result headers and status codes) to
+      page content.
+
+    * Test that the correct view is executed for a given URL.
+
+    * Test that a given request is rendered by a given Django template, with
+      a template context that contains certain values.
+
+Note that the test client is not intended to be a replacement for Twill_,
+Selenium_, or other "in-browser" frameworks. Django's test client has
+a different focus. In short:
+
+    * Use Django's test client to establish that the correct view is being
+      called and that the view is collecting the correct context data.
+
+    * Use in-browser frameworks such as Twill and Selenium to test *rendered*
+      HTML and the *behavior* of Web pages, namely JavaScript functionality.
+
+A comprehensive test suite should use a combination of both test types.
+
+.. _Twill: http://twill.idyll.org/
+.. _Selenium: http://www.openqa.org/selenium/
+
+Overview and a quick example
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+To use the test client, instantiate ``django.test.client.Client`` and retrieve
+Web pages::
+
+    >>> from django.test.client import Client
+    >>> c = Client()
+    >>> response = c.post('/login/', {'username': 'john', 'password': 'smith'})
+    >>> response.status_code
+    200
+    >>> response = c.get('/customer/details/')
+    >>> response.content
+    '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 ...'
+
+As this example suggests, you can instantiate ``Client`` from within a session
+of the Python interactive interpreter.
+
+Note a few important things about how the test client works:
+
+    * The test client does *not* require the Web server to be running. In fact,
+      it will run just fine with no Web server running at all! That's because
+      it avoids the overhead of HTTP and deals directly with the Django
+      framework. This helps make the unit tests run quickly.
+
+    * When retrieving pages, remember to specify the *path* of the URL, not the
+      whole domain. For example, this is correct::
+
+          >>> c.get('/login/')
+
+      This is incorrect::
+
+          >>> c.get('http://www.example.com/login/')
+
+      The test client is not capable of retrieving Web pages that are not
+      powered by your Django project. If you need to retrieve other Web pages,
+      use a Python standard library module such as urllib_ or urllib2_.
+
+    * To resolve URLs, the test client uses whatever URLconf is pointed-to by
+      your :setting:`ROOT_URLCONF` setting.
+
+    * Although the above example would work in the Python interactive
+      interpreter, some of the test client's functionality, notably the
+      template-related functionality, is only available *while tests are
+      running*.
+
+      The reason for this is that Django's test runner performs a bit of black
+      magic in order to determine which template was loaded by a given view.
+      This black magic (essentially a patching of Django's template system in
+      memory) only happens during test running.
+
+.. _urllib: http://docs.python.org/lib/module-urllib.html
+.. _urllib2: http://docs.python.org/lib/module-urllib2.html
+
+Making requests
+~~~~~~~~~~~~~~~
+
+Use the ``django.test.client.Client`` class to make requests. It requires no
+arguments at time of construction::
+
+.. class:: Client()
+
+Once you have a ``Client`` instance, you can call any of the following methods:
+
+.. method:: Client.get(path, data={})
+
+    Makes a GET request on the provided ``path`` and returns a ``Response``
+    object, which is documented below.
+
+    The key-value pairs in the ``data`` dictionary are used to create a GET
+    data payload. For example::
+
+        >>> c = Client()
+        >>> c.get('/customers/details/', {'name': 'fred', 'age': 7})
+
+    ...will result in the evaluation of a GET request equivalent to::
+
+        /customers/details/?name=fred&age=7
+
+.. method:: Client.post(path, data={}, content_type=MULTIPART_CONTENT)
+
+    Makes a POST request on the provided ``path`` and returns a ``Response``
+    object, which is documented below.
+
+    The key-value pairs in the ``data`` dictionary are used to submit POST
+    data. For example::
+
+        >>> c = Client()
+        >>> c.post('/login/', {'name': 'fred', 'passwd': 'secret'})
+
+    ...will result in the evaluation of a POST request to this URL::
+
+        /login/
+
+    ...with this POST data::
+
+        name=fred&passwd=secret
+
+    If you provide ``content_type`` (e.g., ``text/xml`` for an XML payload),
+    the contents of ``data`` will be sent as-is in the POST request, using
+    ``content_type`` in the HTTP ``Content-Type`` header.
+
+    If you don't provide a value for ``content_type``, the values in
+    ``data`` will be transmitted with a content type of ``multipart/form-data``.
+    In this case, the key-value pairs in ``data`` will be encoded as a
+    multipart message and used to create the POST data payload.
+
+    To submit multiple values for a given key -- for example, to specify
+    the selections for a ``<select multiple>`` -- provide the values as a
+    list or tuple for the required key. For example, this value of ``data``
+    would submit three selected values for the field named ``choices``::
+
+        {'choices': ('a', 'b', 'd')}
+
+    Submitting files is a special case. To POST a file, you need only provide
+    the file field name as a key, and a file handle to the file you wish to
+    upload as a value. For example::
+
+        >>> c = Client()
+        >>> f = open('wishlist.doc')
+        >>> c.post('/customers/wishes/', {'name': 'fred', 'attachment': f})
+        >>> f.close()
+
+    (The name ``attachment`` here is not relevant; use whatever name your
+    file-processing code expects.)
+
+    Note that you should manually close the file after it has been provided to
+    ``post()``.
+
+.. method:: Client.login(**credentials)
+
+    **New in Django development version**
+
+    If your site uses Django's :ref:`authentication system<topics-auth>` and you deal with
+    logging in users, you can use the test client's ``login()`` method to
+    simulate the effect of a user logging into the site.
+
+    After you call this method, the test client will have all the cookies and
+    session data required to pass any login-based tests that may form part of
+    a view.
+
+    The format of the ``credentials`` argument depends on which
+    :ref:`authentication backend <authentication-backends>` you're using (which is configured by your
+    :setting:`AUTHENTICATION_BACKENDS` setting). If you're using the standard
+    authentication backend provided by Django (``ModelBackend``),
+    ``credentials`` should be the user's username and password, provided as
+    keyword arguments::
+
+        >>> c = Client()
+        >>> c.login(username='fred', password='secret')
+        
+        # Now you can access a view that's only available to logged-in users.
+
+    If you're using a different authentication backend, this method may require
+    different credentials. It requires whichever credentials are required by
+    your backend's ``authenticate()`` method.
+
+    ``login()`` returns ``True`` if it the credentials were accepted and login
+    was successful.
+
+    Finally, you'll need to remember to create user accounts before you can use
+    this method. As we explained above, the test runner is executed using a
+    test database, which contains no users by default. As a result, user
+    accounts that are valid on your production site will not work under test
+    conditions. You'll need to create users as part of the test suite -- either
+    manually (using the Django model API) or with a test fixture.
+
+.. method:: Client.logout()
+
+    **New in Django development version**
+
+    If your site uses Django's :ref:`authentication system<topics-auth>`, the ``logout()``
+    method can be used to simulate the effect of a user logging out of
+    your site.
+
+    After you call this method, the test client will have all the cookies and
+    session data cleared to defaults. Subsequent requests will appear to
+    come from an AnonymousUser.
+
+Testing responses
+~~~~~~~~~~~~~~~~~
+
+The ``get()`` and ``post()`` methods both return a ``Response`` object. This
+``Response`` object is *not* the same as the ``HttpResponse`` object returned
+Django views; the test response object has some additional data useful for
+test code to verify.
+
+Specifically, a ``Response`` object has the following attributes:
+
+.. class:: Response()
+
+.. attribute:: Response.client``       
+    The test client that was used to make the request that resulted in the
+    response.
+
+.. attribute:: Response.content
+    The body of the response, as a string. This is the final page content as
+    rendered by the view, or any error message.
+
+.. attribute:: Response.context
+    The template ``Context`` instance that was used to render the template that
+    produced the response content.
+
+    If the rendered page used multiple templates, then ``context`` will be a
+    list of ``Context`` objects, in the order in which they were rendered.
+
+.. attribute:: Response.request``      
+    The request data that stimulated the response.
+
+.. attribute:: Response.status_code 
+    The HTTP status of the response, as an integer. See RFC2616_ for a full list
+    of HTTP status codes.
+
+.. attribute:: template
+    The ``Template`` instance that was used to render the final content. Use
+    ``template.name`` to get the template's file name, if the template was
+    loaded from a file. (The name is a string such as ``'admin/index.html'``.)
+    
+    If the rendered page used multiple templates -- e.g., using :ref:`template
+    inheritance<template-inheritance>` -- then ``template`` will be a list of ``Template`` instances,
+    in the order in which they were rendered.
+
+You can also use dictionary syntax on the response object to query the value
+of any settings in the HTTP headers. For example, you could determine the
+content type of a response using ``response['Content-Type']``.
+
+.. _RFC2616: http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html
+
+Exceptions
+~~~~~~~~~~
+
+If you point the test client at a view that raises an exception, that exception
+will be visible in the test case. You can then use a standard ``try...catch``
+block or ``unittest.TestCase.assertRaises()`` to test for exceptions.
+
+The only exceptions that are not visible to the test client are ``Http404``,
+``PermissionDenied`` and ``SystemExit``. Django catches these exceptions
+internally and converts them into the appropriate HTTP response codes. In these
+cases, you can check ``response.status_code`` in your test.
+
+Persistent state
+~~~~~~~~~~~~~~~~
+
+The test client is stateful. If a response returns a cookie, then that cookie
+will be stored in the test client and sent with all subsequent ``get()`` and
+``post()`` requests.
+
+Expiration policies for these cookies are not followed. If you want a cookie
+to expire, either delete it manually or create a new ``Client`` instance (which
+will effectively delete all cookies).
+
+A test client has two attributes that store persistent state information. You
+can access these properties as part of a test condition.
+
+.. attribute:: Client.cookies
+    A Python ``SimpleCookie`` object, containing the current values of all the
+    client cookies. See the `Cookie module documentation`_ for more.
+
+.. attribute:: Client.session
+    A dictionary-like object containing session information. See the :ref:`session
+    documentation<topics-http-sessions>` for full details.
+
+.. _Cookie module documentation: http://docs.python.org/lib/module-Cookie.html
+
+Example
+~~~~~~~
+
+The following is a simple unit test using the test client::
+
+    import unittest
+    from django.test.client import Client
+
+    class SimpleTest(unittest.TestCase):
+        def setUp(self):
+            # Every test needs a client.
+            self.client = Client()
+
+        def test_details(self):
+            # Issue a GET request.
+            response = self.client.get('/customer/details/')
+
+            # Check that the response is 200 OK.
+            self.failUnlessEqual(response.status_code, 200)
+
+            # Check that the rendered context contains 5 customers.
+            self.failUnlessEqual(len(response.context['customers']), 5)
+
+TestCase
+--------
+
+.. currentmodule:: django.test
+
+Normal Python unit test classes extend a base class of ``unittest.TestCase``.
+Django provides an extension of this base class:
+
+.. class:: TestCase()
+
+This class provides some additional capabilities that can be useful for testing
+Web sites.
+
+Converting a normal ``unittest.TestCase`` to a Django ``TestCase`` is easy:
+just change the base class of your test from ``unittest.TestCase`` to
+``django.test.TestCase``. All of the standard Python unit test functionality
+will continue to be available, but it will be augmented with some useful
+additions.
+
+Default test client
+~~~~~~~~~~~~~~~~~~~
+
+**New in Django development version**
+
+.. attribute:: TestCase.client
+
+Every test case in a ``django.test.TestCase`` instance has access to an
+instance of a Django test client. This client can be accessed as
+``self.client``. This client is recreated for each test, so you don't have to
+worry about state (such as cookies) carrying over from one test to another.
+
+This means, instead of instantiating a ``Client`` in each test::
+
+    import unittest
+    from django.test.client import Client
+
+    class SimpleTest(unittest.TestCase):
+        def test_details(self):
+            client = Client()
+            response = client.get('/customer/details/')
+            self.failUnlessEqual(response.status_code, 200)
+
+        def test_index(self):
+            client = Client()
+            response = client.get('/customer/index/')
+            self.failUnlessEqual(response.status_code, 200)
+
+...you can just refer to ``self.client``, like so::
+
+    from django.test import TestCase
+
+    class SimpleTest(TestCase):
+        def test_details(self):
+            response = self.client.get('/customer/details/')
+            self.failUnlessEqual(response.status_code, 200)
+
+        def test_index(self):
+            response = self.client.get('/customer/index/')
+            self.failUnlessEqual(response.status_code, 200)
+
+.. _topics-testing-fixtures:
+
+Fixture loading
+~~~~~~~~~~~~~~~
+
+.. attribute:: TestCase.fixtures
+
+A test case for a database-backed Web site isn't much use if there isn't any
+data in the database. To make it easy to put test data into the database,
+Django's custom ``TestCase`` class provides a way of loading **fixtures**.
+
+A fixture is a collection of data that Django knows how to import into a
+database. For example, if your site has user accounts, you might set up a
+fixture of fake user accounts in order to populate your database during tests.
+
+The most straightforward way of creating a fixture is to use the
+``manage.py dumpdata`` command. This assumes you already have some data in
+your database. See the :djadmin:`dumpdata documentation<dumpdata>` for more details.
+
+.. note::
+    If you've ever run ``manage.py syncdb``, you've already used a fixture
+    without even knowing it! When you call ``syncdb`` in the database for
+    the first time, Django installs a fixture called ``initial_data``.
+    This gives you a way of populating a new database with any initial data,
+    such as a default set of categories.
+
+    Fixtures with other names can always be installed manually using the
+    ``manage.py loaddata`` command.
+
+Once you've created a fixture and placed it somewhere in your Django project,
+you can use it in your unit tests by specifying a ``fixtures`` class attribute
+on your ``django.test.TestCase`` subclass::
+
+    from django.test import TestCase
+    from myapp.models import Animal
+
+    class AnimalTestCase(TestCase):
+        fixtures = ['mammals.json', 'birds']
+
+        def setUp(self):
+            # Test definitions as before.
+
+        def testFluffyAnimals(self):
+            # A test that uses the fixtures.
+
+Here's specifically what will happen:
+
+    * At the start of each test case, before ``setUp()`` is run, Django will
+      flush the database, returning the database to the state it was in
+      directly after ``syncdb`` was called.
+
+    * Then, all the named fixtures are installed. In this example, Django will
+      install any JSON fixture named ``mammals``, followed by any fixture named
+      ``birds``. See the :djadmin:`loaddata documentation<loaddata>` for more details on defining
+      and installing fixtures.
+
+This flush/load procedure is repeated for each test in the test case, so you
+can be certain that the outcome of a test will not be affected by
+another test, or by the order of test execution.
+
+URLconf configuration
+~~~~~~~~~~~~~~~~~~~~~
+
+**New in Django development version**
+
+.. attribute:: TestCase.urls
+
+If your application provides views, you may want to include tests that
+use the test client to exercise those views. However, an end user is free
+to deploy the views in your application at any URL of their choosing.
+This means that your tests can't rely upon the fact that your views will
+be available at a particular URL.
+
+In order to provide a reliable URL space for your test,
+``django.test.TestCase`` provides the ability to customize the URLconf
+configuration for the duration of the execution of a test suite.
+If your ``TestCase`` instance defines an ``urls`` attribute, the
+``TestCase`` will use the value of that attribute as the ``ROOT_URLCONF``
+for the duration of that test. 
+
+For example::
+
+    from django.test import TestCase
+    
+    class TestMyViews(TestCase):
+        urls = 'myapp.test_urls'
+
+        def testIndexPageView(self):
+            # Here you'd test your view using ``Client``.
+
+This test case will use the contents of ``myapp.test_urls`` as the
+URLconf for the duration of the test case.
+
+.. _emptying-test-outbox:
+
+Emptying the test outbox
+~~~~~~~~~~~~~~~~~~~~~~~~
+
+**New in Django development version**
+
+If you use Django's custom ``TestCase`` class, the test runner will clear the
+contents of the test e-mail outbox at the start of each test case.
+
+For more detail on e-mail services during tests, see `E-mail services`_.
+
+Assertions
+~~~~~~~~~~
+
+**New in Django development version**
+
+As Python's normal ``unittest.TestCase`` class implements assertion
+methods such as ``assertTrue`` and ``assertEquals``, Django's custom
+``TestCase`` class provides a number of custom assertion methods that are
+useful for testing Web applications:
+
+.. method:: TestCase.assertContains(response, text, count=None, status_code=200)
+    Asserts that a ``Response`` instance produced the given ``status_code`` and
+    that ``text`` appears in the content of the response. If ``count`` is
+    provided, ``text`` must occur exactly ``count`` times in the response.
+
+.. method:: TestCase.assertNotContains(response, text, status_code=200)
+    Asserts that a ``Response`` instance produced the given ``status_code`` and
+    that ``text`` does not appears in the content of the response.
+
+.. method:: assertFormError(response, form, field, errors)
+    Asserts that a field on a form raises the provided list of errors when
+    rendered on the form.
+
+    ``form`` is the name the ``Form`` instance was given in the template
+    context. Note that this works only for ``forms.Form`` instances, not
+    ``oldforms.Form`` instances.
+
+    ``field`` is the name of the field on the form to check. If ``field``
+    has a value of ``None``, non-field errors (errors you can access via
+    ``form.non_field_errors()``) will be checked.
+
+    ``errors`` is an error string, or a list of error strings, that are
+    expected as a result of form validation.
+
+.. method:: assertTemplateUsed(response, template_name)
+    Asserts that the template with the given name was used in rendering the
+    response.
+
+    The name is a string such as ``'admin/index.html'``.
+
+.. method:: assertTemplateNotUsed(response, template_name)
+    Asserts that the template with the given name was *not* used in rendering
+    the response.
+
+.. method:: assertRedirects(response, expected_url, status_code=302, target_status_code=200)
+    Asserts that the response return a ``status_code`` redirect status,
+    it redirected to ``expected_url`` (including any GET data), and the subsequent
+    page was received with ``target_status_code``.
+
+E-mail services
+---------------
+
+**New in Django development version**
+
+If any of your Django views send e-mail using :ref:`Django's e-mail
+functionality <topics-email>`, you probably don't want to send e-mail each time
+you run a test using that view. For this reason, Django's test runner
+automatically redirects all Django-sent e-mail to a dummy outbox. This lets you
+test every aspect of sending e-mail -- from the number of messages sent to the
+contents of each message -- without actually sending the messages.
+
+The test runner accomplishes this by transparently replacing the normal
+:class:`~django.core.mail.SMTPConnection` class with a different version. (Don't
+worry -- this has no effect on any other e-mail senders outside of Django, such
+as your machine's mail server, if you're running one.)
+
+.. currentmodule:: django.core.mail
+
+.. data:: django.core.mail.output
+
+During test running, each outgoing e-mail is saved in
+``django.core.mail.outbox``. This is a simple list of all :class:`<~django.core.mail.EmailMessage>`
+instances that have been sent. It does not exist under normal execution
+conditions, i.e., when you're not running unit tests. The outbox is created
+during test setup, along with the dummy :class:`<~django.core.mail.SMTPConnection>`. When the test
+framework is torn down, the standard :class:`<~django.core.mail.SMTPConnection>` class is restored, and
+the test outbox is destroyed.
+
+Here's an example test that examines ``django.core.mail.outbox`` for length
+and contents::
+
+    from django.core import mail
+    from django.test import TestCase
+
+    class EmailTest(TestCase):
+        def test_send_email(self):
+            # Send message.
+            mail.send_mail('Subject here', 'Here is the message.',
+                'from@example.com', ['to@example.com'],
+                fail_silently=False)
+
+            # Test that one message has been sent.
+            self.assertEqual(len(mail.outbox), 1)
+
+            # Verify that the subject of the first message is correct.
+            self.assertEqual(mail.outbox[0].subject, 'Subject here')
+
+As noted :ref:`previously <emptying-test-outbox>`, the test outbox is emptied at the start of every
+test in a Django ``TestCase``. To empty the outbox manually, assign the
+empty list to ``mail.outbox``::
+
+    from django.core import mail
+
+    # Empty the test outbox
+    mail.outbox = []
+
+Using different testing frameworks
+==================================
+
+Clearly, ``doctest`` and ``unittest`` are not the only Python testing
+frameworks. While Django doesn't provide explicit support for alternative
+frameworks, it does provide a way to invoke tests constructed for an
+alternative framework as if they were normal Django tests.
+
+When you run ``./manage.py test``, Django looks at the :setting:`TEST_RUNNER`
+setting to determine what to do. By default, :setting:`TEST_RUNNER` points to
+``'django.test.simple.run_tests'``. This method defines the default Django
+testing behavior. This behavior involves:
+
+    #. Performing global pre-test setup.
+
+    #. Creating the test database.
+
+    #. Running ``syncdb`` to install models and initial data into the test
+       database.
+
+    #. Looking for unit tests and doctests in the ``models.py`` and
+       ``tests.py`` files in each installed application.
+
+    #. Running the unit tests and doctests that are found.
+
+    #. Destroying the test database.
+
+    #. Performing global post-test teardown.
+
+If you define your own test runner method and point :setting:`TEST_RUNNER` at
+that method, Django will execute your test runner whenever you run ``./manage.py
+test``. In this way, it is possible to use any test framework that can be
+executed from Python code.
+
+Defining a test runner
+----------------------
+
+**New in Django development version**
+
+.. currentmodule:: django.test.simple
+
+By convention, a test runner should be called ``run_tests``. The only strict
+requirement is that it has the same arguments as the Django test runner:
+
+.. function:: run_tests(test_labels, verbosity=1, interactive=True, extra_tests=[])
+    ``test_labels`` is a list of strings describing the tests to be run. A test
+    label can take one of three forms:
+
+        * ``app.TestCase.test_method`` -- Run a single test method in a test
+          case.
+        * ``app.TestCase`` -- Run all the test methods in a test case.
+        * ``app`` -- Search for and run all tests in the named application.
+
+    If ``test_labels`` has a value of ``None``, the test runner should run
+    search for tests in all the applications in :setting:`INSTALLED_APPS`.
+
+    ``verbosity`` determines the amount of notification and debug information
+    that will be printed to the console; ``0`` is no output, ``1`` is normal
+    output, and ``2`` is verbose output.
+
+    If ``interactive`` is ``True``, the test suite has permission to ask the
+    user for instructions when the test suite is executed. An example of this
+    behavior would be asking for permission to delete an existing test
+    database. If ``interactive`` is ``False``, the test suite must be able to
+    run without any manual intervention.
+
+    ``extra_tests`` is a list of extra ``TestCase`` instances to add to the
+    suite that is executed by the test runner. These extra tests are run
+    in addition to those discovered in the modules listed in ``module_list``.
+
+    This method should return the number of tests that failed.
+
+Testing utilities
+-----------------
+
+.. module:: django.test.utils
+   :synopsis: Helpers to write custom test runners.
+
+To assist in the creation of your own test runner, Django provides
+a number of utility methods in the ``django.test.utils`` module.
+
+.. function:: setup_test_environment()
+    Performs any global pre-test setup, such as the installing the
+    instrumentation of the template rendering system and setting up
+    the dummy ``SMTPConnection``.
+
+.. function:: teardown_test_environment()
+    Performs any global post-test teardown, such as removing the
+    black magic hooks into the template system and restoring normal e-mail
+    services.
+
+The creation module of the database backend (``connection.creation``) also
+provides some utilities that can be useful during testing.
+
+.. function:: create_test_db(verbosity=1, autoclobber=False)
+    Creates a new test database and runs ``syncdb`` against it.
+
+    ``verbosity`` has the same behavior as in ``run_tests()``.
+
+    ``autoclobber`` describes the behavior that will occur if a database with
+    the same name as the test database is discovered:
+
+        * If ``autoclobber`` is ``False``, the user will be asked to approve
+          destroying the existing database. ``sys.exit`` is called if the user
+          does not approve.
+
+        * If autoclobber is ``True``, the database will be destroyed without
+          consulting the user.
+
+    ``create_test_db()`` has the side effect of modifying
+    ``settings.DATABASE_NAME`` to match the name of the test database.
+
+    **New in Django development version:** This function returns the name of
+    the test database that it created.
+
+.. function:: destroy_test_db(old_database_name, verbosity=1)
+    Destroys the database whose name is in the :setting:`DATABASE_NAME` setting
+    and restores the value of :setting:`DATABASE_NAME` to the provided name.
+
+    ``verbosity`` has the same behavior as in ``run_tests()``.