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diff --git a/parts/django/docs/topics/testing.txt b/parts/django/docs/topics/testing.txt new file mode 100644 index 0000000..155f758 --- /dev/null +++ b/parts/django/docs/topics/testing.txt @@ -0,0 +1,1613 @@ +=========================== +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. However, the database is not refreshed between doctests, +so if your doctest requires a certain state you should consider flushing the +database or loading a fixture. (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/library/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. + +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/library/unittest.html +.. _standard library unittest documentation: unittest_ +.. _suggested organization: http://docs.python.org/library/unittest.html#organizing-tests + +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 the :djadmin:`test` command of +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``. + +.. versionadded:: 1.0 + You can now choose which test to run. + +You can be even *more* specific by naming an individual test case. 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 + +.. versionadded:: 1.2 + The ability to select individual doctests was added. + +You can use the same rules if you're using doctests. Django will use the +test label as a path to the test method or class that you want to run. +If your ``models.py`` or ``tests.py`` has a function with a doctest, or +class with a class-level doctest, you can invoke that test by appending the +name of the test method or class to the label:: + + $ ./manage.py test animals.classify + +If you want to run the doctest for a specific method in a class, add the +name of the method to the label:: + + $ ./manage.py test animals.Classifier.run + +If you're using a ``__test__`` dictionary to specify doctests for a +module, Django will use the label as a key in the ``__test__`` dictionary +for defined in ``models.py`` and ``tests.py``. + +.. versionadded:: 1.2 + You can now trigger a graceful exit from a test run by pressing ``Ctrl-C``. + +If you press ``Ctrl-C`` while the tests are running, the test runner will +wait for the currently running test to complete and then exit gracefully. +During a graceful exit the test runner will output details of any test +failures, report on how many tests were run and how many errors and failures +were encountered, and destroy any test databases as usual. Thus pressing +``Ctrl-C`` can be very useful if you forget to pass the :djadminopt:`--failfast` +option, notice that some tests are unexpectedly failing, and want to get details +on the failures without waiting for the full test run to complete. + +If you do not want to wait for the currently running test to finish, you +can press ``Ctrl-C`` a second time and the test run will halt immediately, +but not gracefully. No details of the tests run before the interruption will +be reported, and any test databases created by the run will not be destroyed. + +.. admonition:: Test with warnings enabled + + It is a good idea to run your tests with ``python -Wall manage.py + test``. This will allow you to catch any deprecation warnings that + might be in your code. Django (as well as many other libraries) use + warnings to flag when features are deprecated. It can also flag + areas in your code that are not strictly wrong, but may benefit + from a better implementation. + +Running tests outside the test runner +------------------------------------- + +If you want to run tests outside of ``./manage.py test`` -- for example, +from a shell prompt -- you will need to set up the test +environment first. Django provides a convenience method to do this:: + + >>> from django.test.utils import setup_test_environment + >>> setup_test_environment() + +This convenience method sets up the test database, and puts other +Django features into modes that allow for repeatable testing. + +The call to :meth:`~django.test.utils.setup_test_environment` is made +automatically as part of the setup of `./manage.py test`. You only +need to manually invoke this method if you're not using running your +tests via Django's test runner. + +The test database +----------------- + +Tests that require a database (namely, model tests) will not use your "real" +(production) database. Separate, blank databases are created for the tests. + +Regardless of whether the tests pass or fail, the test databases are destroyed +when all the tests have been executed. + +By default the test databases get their names by prepending ``test_`` +to the value of the :setting:`NAME` settings for the databases +defined in :setting:`DATABASES`. 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 +:setting:`TEST_NAME` in the dictionary for any given database in +:setting:`DATABASES`. + +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:`ENGINE`, :setting:`USER`, :setting:`HOST`, etc. The test +database is created by the user specified by ``USER``, so you'll need +to make sure that the given user account has sufficient privileges to +create a new database on the system. + +.. versionadded:: 1.0 + +For fine-grained control over the character encoding of your test +database, use the :setting:`TEST_CHARSET` option. If you're using +MySQL, you can also use the :setting:`TEST_COLLATION` option to +control the particular collation used by the test database. See the +:doc:`settings documentation </ref/settings>` for details of these +advanced settings. + +.. _topics-testing-masterslave: + +Testing master/slave configurations +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +.. versionadded:: 1.2 + +If you're testing a multiple database configuration with master/slave +replication, this strategy of creating test databases poses a problem. +When the test databases are created, there won't be any replication, +and as a result, data created on the master won't be seen on the +slave. + +To compensate for this, Django allows you to define that a database is +a *test mirror*. Consider the following (simplified) example database +configuration:: + + DATABASES = { + 'default': { + 'ENGINE': 'django.db.backends.mysql', + 'NAME': 'myproject', + 'HOST': 'dbmaster', + # ... plus some other settings + }, + 'slave': { + 'ENGINE': 'django.db.backends.mysql', + 'NAME': 'myproject', + 'HOST': 'dbslave', + 'TEST_MIRROR': 'default' + # ... plus some other settings + } + } + +In this setup, we have two database servers: ``dbmaster``, described +by the database alias ``default``, and ``dbslave`` described by the +alias ``slave``. As you might expect, ``dbslave`` has been configured +by the database administrator as a read slave of ``dbmaster``, so in +normal activity, any write to ``default`` will appear on ``slave``. + +If Django created two independent test databases, this would break any +tests that expected replication to occur. However, the ``slave`` +database has been configured as a test mirror (using the +:setting:`TEST_MIRROR` setting), indicating that under testing, +``slave`` should be treated as a mirror of ``default``. + +When the test environment is configured, a test version of ``slave`` +will *not* be created. Instead the connection to ``slave`` +will be redirected to point at ``default``. As a result, writes to +``default`` will appear on ``slave`` -- but because they are actually +the same database, not because there is data replication between the +two databases. + +.. _topics-testing-creation-dependencies: + +Controlling creation order for test databases +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +.. versionadded:: 1.2.4 + +By default, Django will always create the ``default`` database first. +However, no guarantees are made on the creation order of any other +databases in your test setup. + +If your database configuration requires a specific creation order, you +can specify the dependencies that exist using the +:setting:`TEST_DEPENDENCIES` setting. Consider the following +(simplified) example database configuration:: + + DATABASES = { + 'default': { + # ... db settings + 'TEST_DEPENDENCIES': ['diamonds'] + }, + 'diamonds': { + # ... db settings + }, + 'clubs': { + # ... db settings + 'TEST_DEPENDENCIES': ['diamonds'] + }, + 'spades': { + # ... db settings + 'TEST_DEPENDENCIES': ['diamonds','hearts'] + }, + 'hearts': { + # ... db settings + 'TEST_DEPENDENCIES': ['diamonds','clubs'] + } + } + +Under this configuration, the ``diamonds`` database will be created first, +as it is the only database alias without dependencies. The ``default``` and +``clubs`` alias will be created next (although the order of creation of this +pair is not guaranteed); then ``hearts``; and finally ``spades``. + +If there are any circular dependencies in the +:setting:`TEST_DEPENDENCIES` definition, an ``ImproperlyConfigured`` +exception will be raised. + +Other test conditions +--------------------- + +Regardless of the value of the :setting:`DEBUG` setting in your configuration +file, all Django tests run with :setting:`DEBUG`\=False. This is to ensure that +the observed output of your code matches what will be seen in a production +setting. + +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://seleniumhq.org/ + +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. + + * By default, the test client will disable any CSRF checks + performed by your site. + + .. versionadded:: 1.2.2 + + If, for some reason, you *want* the test client to perform CSRF + checks, you can create an instance of the test client that + enforces CSRF checks. To do this, pass in the + ``enforce_csrf_checks`` argument when you construct your + client:: + + >>> from django.test import Client + >>> csrf_client = Client(enforce_csrf_checks=True) + + +.. _urllib: http://docs.python.org/library/urllib.html +.. _urllib2: http://docs.python.org/library/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={}, follow=False, **extra) + + + 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 + + The ``extra`` keyword arguments parameter can be used to specify + headers to be sent in the request. For example:: + + >>> c = Client() + >>> c.get('/customers/details/', {'name': 'fred', 'age': 7}, + ... HTTP_X_REQUESTED_WITH='XMLHttpRequest') + + ...will send the HTTP header ``HTTP_X_REQUESTED_WITH`` to the + details view, which is a good way to test code paths that use the + :meth:`django.http.HttpRequest.is_ajax()` method. + + .. versionadded:: 1.1 + + If you already have the GET arguments in URL-encoded form, you can + use that encoding instead of using the data argument. For example, + the previous GET request could also be posed as:: + + >>> c = Client() + >>> c.get('/customers/details/?name=fred&age=7') + + If you provide a URL with both an encoded GET data and a data argument, + the data argument will take precedence. + + If you set ``follow`` to ``True`` the client will follow any redirects + and a ``redirect_chain`` attribute will be set in the response object + containing tuples of the intermediate urls and status codes. + + If you had an url ``/redirect_me/`` that redirected to ``/next/``, that + redirected to ``/final/``, this is what you'd see:: + + >>> response = c.get('/redirect_me/', follow=True) + >>> response.redirect_chain + [(u'http://testserver/next/', 302), (u'http://testserver/final/', 302)] + + .. method:: Client.post(path, data={}, content_type=MULTIPART_CONTENT, follow=False, **extra) + + 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 if you wish to use the same file handle for multiple + ``post()`` calls then you will need to manually reset the file + pointer between posts. The easiest way to do this is to + manually close the file after it has been provided to + ``post()``, as demonstrated above. + + You should also ensure that the file is opened in a way that + allows the data to be read. If your file contains binary data + such as an image, this means you will need to open the file in + ``rb`` (read binary) mode. + + The ``extra`` argument acts the same as for :meth:`Client.get`. + + .. versionchanged:: 1.1 + + If the URL you request with a POST contains encoded parameters, these + parameters will be made available in the request.GET data. For example, + if you were to make the request:: + + >>> c.post('/login/?visitor=true', {'name': 'fred', 'passwd': 'secret'}) + + ... the view handling this request could interrogate request.POST + to retrieve the username and password, and could interrogate request.GET + to determine if the user was a visitor. + + If you set ``follow`` to ``True`` the client will follow any redirects + and a ``redirect_chain`` attribute will be set in the response object + containing tuples of the intermediate urls and status codes. + + .. method:: Client.head(path, data={}, follow=False, **extra) + + .. versionadded:: 1.1 + + Makes a HEAD request on the provided ``path`` and returns a ``Response`` + object. Useful for testing RESTful interfaces. Acts just like + :meth:`Client.get` except it does not return a message body. + + If you set ``follow`` to ``True`` the client will follow any redirects + and a ``redirect_chain`` attribute will be set in the response object + containing tuples of the intermediate urls and status codes. + + .. method:: Client.options(path, data={}, follow=False, **extra) + + .. versionadded:: 1.1 + + Makes an OPTIONS request on the provided ``path`` and returns a + ``Response`` object. Useful for testing RESTful interfaces. + + If you set ``follow`` to ``True`` the client will follow any redirects + and a ``redirect_chain`` attribute will be set in the response object + containing tuples of the intermediate urls and status codes. + + The ``extra`` argument acts the same as for :meth:`Client.get`. + + .. method:: Client.put(path, data={}, content_type=MULTIPART_CONTENT, follow=False, **extra) + + .. versionadded:: 1.1 + + Makes a PUT request on the provided ``path`` and returns a + ``Response`` object. Useful for testing RESTful interfaces. Acts just + like :meth:`Client.post` except with the PUT request method. + + If you set ``follow`` to ``True`` the client will follow any redirects + and a ``redirect_chain`` attribute will be set in the response object + containing tuples of the intermediate urls and status codes. + + .. method:: Client.delete(path, follow=False, **extra) + + .. versionadded:: 1.1 + + Makes an DELETE request on the provided ``path`` and returns a + ``Response`` object. Useful for testing RESTful interfaces. + + If you set ``follow`` to ``True`` the client will follow any redirects + and a ``redirect_chain`` attribute will be set in the response object + containing tuples of the intermediate urls and status codes. + + The ``extra`` argument acts the same as for :meth:`Client.get`. + + .. method:: Client.login(**credentials) + + .. versionadded:: 1.0 + + If your site uses Django's :doc:`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. Remember that if you want your test user to have a password, + you can't set the user's password by setting the password attribute + directly -- you must use the + :meth:`~django.contrib.auth.models.User.set_password()` function to + store a correctly hashed password. Alternatively, you can use the + :meth:`~django.contrib.auth.models.UserManager.create_user` helper + method to create a new user with a correctly hashed password. + + .. method:: Client.logout() + + .. versionadded:: 1.0 + + If your site uses Django's :doc:`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:: client + + The test client that was used to make the request that resulted in the + response. + + .. attribute:: 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:: 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. + + .. versionadded:: 1.1 + + Regardless of the number of templates used during rendering, you can + retrieve context values using the ``[]`` operator. For example, the + context variable ``name`` could be retrieved using:: + + >>> response = client.get('/foo/') + >>> response.context['name'] + 'Arthur' + + .. attribute:: request + + The request data that stimulated the response. + + .. attribute:: 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...except`` +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 + :doc:`session documentation</topics/http/sessions>` for full details. + + To modify the session and then save it, it must be stored in a variable + first (because a new ``SessionStore`` is created every time this property + is accessed):: + + def test_something(self): + session = self.client.session + session['somekey'] = 'test' + session.save() + +.. _Cookie module documentation: http://docs.python.org/library/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. + +.. versionadded:: 1.1 + +.. class:: TransactionTestCase() + +Django ``TestCase`` classes make use of database transaction facilities, if +available, to speed up the process of resetting the database to a known state +at the beginning of each test. A consequence of this, however, is that the +effects of transaction commit and rollback cannot be tested by a Django +``TestCase`` class. If your test requires testing of such transactional +behavior, you should use a Django ``TransactionTestCase``. + +``TransactionTestCase`` and ``TestCase`` are identical except for the manner +in which the database is reset to a known state and the ability for test code +to test the effects of commit and rollback. A ``TransactionTestCase`` resets +the database before the test runs by truncating all tables and reloading +initial data. A ``TransactionTestCase`` may call commit and rollback and +observe the effects of these calls on the database. + +A ``TestCase``, on the other hand, does not truncate tables and reload initial +data at the beginning of a test. Instead, it encloses the test code in a +database transaction that is rolled back at the end of the test. It also +prevents the code under test from issuing any commit or rollback operations +on the database, to ensure that the rollback at the end of the test restores +the database to its initial state. In order to guarantee that all ``TestCase`` +code starts with a clean database, the Django test runner runs all ``TestCase`` +tests first, before any other tests (e.g. doctests) that may alter the +database without restoring it to its original state. + +When running on a database that does not support rollback (e.g. MySQL with the +MyISAM storage engine), ``TestCase`` falls back to initializing the database +by truncating tables and reloading initial data. + + +.. note:: + The ``TestCase`` use of rollback to un-do the effects of the test code + may reveal previously-undetected errors in test code. For example, + test code that assumes primary keys values will be assigned starting at + one may find that assumption no longer holds true when rollbacks instead + of table truncation are being used to reset the database. Similarly, + the reordering of tests so that all ``TestCase`` classes run first may + reveal unexpected dependencies on test case ordering. In such cases a + quick fix is to switch the ``TestCase`` to a ``TransactionTestCase``. + A better long-term fix, that allows the test to take advantage of the + speed benefit of ``TestCase``, is to fix the underlying test problem. + + +Default test client +~~~~~~~~~~~~~~~~~~~ + +.. versionadded:: 1.0 + +.. 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 +:djadmin:`manage.py dumpdata <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 :djadmin:`manage.py syncdb<syncdb>`, you've + already used a fixture without even knowing it! When you call + :djadmin:`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 :djadmin:`manage.py loaddata<loaddata>` command. + +Once you've created a fixture and placed it in a ``fixtures`` directory in one +of your :setting:`INSTALLED_APPS`, you can use it in your unit tests by +specifying a ``fixtures`` class attribute on your :class:`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. + call_setup_methods() + + def testFluffyAnimals(self): + # A test that uses the fixtures. + call_some_test_code() + +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 :djadmin:`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 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 +~~~~~~~~~~~~~~~~~~~~~ + +.. versionadded:: 1.0 + +.. 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``. + call_some_test_code() + +This test case will use the contents of ``myapp.test_urls`` as the +URLconf for the duration of the test case. + +.. _emptying-test-outbox: + +Multi-database support +~~~~~~~~~~~~~~~~~~~~~~ + +.. attribute:: TestCase.multi_db + +.. versionadded:: 1.2 + +Django sets up a test database corresponding to every database that is +defined in the :setting:`DATABASES` definition in your settings +file. However, a big part of the time taken to run a Django TestCase +is consumed by the call to ``flush`` that ensures that you have a +clean database at the start of each test run. If you have multiple +databases, multiple flushes are required (one for each database), +which can be a time consuming activity -- especially if your tests +don't need to test multi-database activity. + +As an optimization, Django only flushes the ``default`` database at +the start of each test run. If your setup contains multiple databases, +and you have a test that requires every database to be clean, you can +use the ``multi_db`` attribute on the test suite to request a full +flush. + +For example:: + + class TestMyViews(TestCase): + multi_db = True + + def testIndexPageView(self): + call_some_test_code() + +This test case will flush *all* the test databases before running +``testIndexPageView``. + +Emptying the test outbox +~~~~~~~~~~~~~~~~~~~~~~~~ + +.. versionadded:: 1.0 + +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 +~~~~~~~~~~ + +.. versionadded:: 1.0 + +.. versionchanged:: 1.2 + Addded ``msg_prefix`` argument. + +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: + +The failure messages given by the assertion methods can be customized +with the ``msg_prefix`` argument. This string will be prefixed to any +failure message generated by the assertion. This allows you to provide +additional details that may help you to identify the location and +cause of an failure in your test suite. + +.. method:: TestCase.assertContains(response, text, count=None, status_code=200, msg_prefix='') + + 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, msg_prefix='') + + Asserts that a ``Response`` instance produced the given ``status_code`` and + that ``text`` does not appears in the content of the response. + +.. method:: TestCase.assertFormError(response, form, field, errors, msg_prefix='') + + 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. + + ``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:: TestCase.assertTemplateUsed(response, template_name, msg_prefix='') + + 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:: TestCase.assertTemplateNotUsed(response, template_name, msg_prefix='') + + Asserts that the template with the given name was *not* used in rendering + the response. + +.. method:: TestCase.assertRedirects(response, expected_url, status_code=302, target_status_code=200, msg_prefix='') + + Asserts that the response return a ``status_code`` redirect status, it + redirected to ``expected_url`` (including any GET data), and the final + page was received with ``target_status_code``. + + .. versionadded:: 1.1 + + If your request used the ``follow`` argument, the ``expected_url`` and + ``target_status_code`` will be the url and status code for the final + point of the redirect chain. + +.. _topics-testing-email: + +E-mail services +--------------- + +.. versionadded:: 1.0 + +If any of your Django views send e-mail using :doc:`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 +email backend with a testing backend. +(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.outbox + +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. +The ``outbox`` attribute is a special attribute that is created *only* when +the ``locmem`` e-mail backend is used. It doesn't normally exist as part of the +:mod:`django.core.mail` module and you can't import it directly. The code +below shows how to access this attribute correctly. + +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.assertEquals(len(mail.outbox), 1) + + # Verify that the subject of the first message is correct. + self.assertEquals(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.DjangoTestSuiteRunner'``. This class defines the default Django +testing behavior. This behavior involves: + + #. Performing global pre-test setup. + + #. Looking for unit tests and doctests in the ``models.py`` and + ``tests.py`` files in each installed application. + + #. Creating the test databases. + + #. Running ``syncdb`` to install models and initial data into the test + databases. + + #. Running the unit tests and doctests that are found. + + #. Destroying the test databases. + + #. Performing global post-test teardown. + +If you define your own test runner class and point :setting:`TEST_RUNNER` at +that class, 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, or to modify the Django test execution +process to satisfy whatever testing requirements you may have. + +.. _topics-testing-test_runner: + +Defining a test runner +---------------------- + +.. versionchanged:: 1.2 + Prior to 1.2, test runners were a single function, not a class. + +.. currentmodule:: django.test.simple + +A test runner is a class defining a ``run_tests()`` method. Django ships +with a ``DjangoTestSuiteRunner`` class that defines the default Django +testing behavior. This class defines the ``run_tests()`` entry point, +plus a selection of other methods that are used to by ``run_tests()`` to +set up, execute and tear down the test suite. + +.. class:: DjangoTestSuiteRunner(verbosity=1, interactive=True, failfast=True, **kwargs) + + ``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. + + If ``failfast`` is ``True``, the test suite will stop running after the + first test failure is detected. + + Django will, from time to time, extend the capabilities of + the test runner by adding new arguments. The ``**kwargs`` declaration + allows for this expansion. If you subclass ``DjangoTestSuiteRunner`` or + write your own test runner, ensure accept and handle the ``**kwargs`` + parameter. + +.. method:: DjangoTestSuiteRunner.run_tests(test_labels, extra_tests=None, **kwargs) + + Run the test suite. + + ``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`. + + ``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 ``test_labels``. + + This method should return the number of tests that failed. + +.. method:: DjangoTestSuiteRunner.setup_test_environment(**kwargs) + + Sets up the test environment ready for testing. + +.. method:: DjangoTestSuiteRunner.build_suite(test_labels, extra_tests=None, **kwargs) + + Constructs a test suite that matches the test labels provided. + + ``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`. + + ``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 ``test_labels``. + + Returns a ``TestSuite`` instance ready to be run. + +.. method:: DjangoTestSuiteRunner.setup_databases(**kwargs) + + Creates the test databases. + + Returns a data structure that provides enough detail to undo the changes + that have been made. This data will be provided to the ``teardown_databases()`` + function at the conclusion of testing. + +.. method:: DjangoTestSuiteRunner.run_suite(suite, **kwargs) + + Runs the test suite. + + Returns the result produced by the running the test suite. + +.. method:: DjangoTestSuiteRunner.teardown_databases(old_config, **kwargs) + + Destroys the test databases, restoring pre-test conditions. + + ``old_config`` is a data structure defining the changes in the + database configuration that need to be reversed. It is the return + value of the ``setup_databases()`` method. + +.. method:: DjangoTestSuiteRunner.teardown_test_environment(**kwargs) + + Restores the pre-test environment. + +.. method:: DjangoTestSuiteRunner.suite_result(suite, result, **kwargs) + + Computes and returns a return code based on a test suite, and the result + from that test suite. + + +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. + + Returns the name of the test database that it created. + + ``create_test_db()`` has the side effect of modifying the value of + :setting:`NAME` in :setting:`DATABASES` to match the name of the test + database. + + .. versionchanged:: 1.0 + ``create_test_db()`` now returns the name of the test database. + +.. function:: destroy_test_db(old_database_name, verbosity=1) + + Destroys the database whose name is in stored in :setting:`NAME` in the + :setting:`DATABASES`, and sets :setting:`NAME` to use the + provided name. + + ``verbosity`` has the same behavior as in ``run_tests()``. |