Source code
Revision control
Copy as Markdown
Other Tools
# Mn Python tests
_Marionette_ is the codename of a [remote protocol] built in to
Firefox as well as the name of a functional test framework for
automating user interface tests.
The in-tree test framework supports tests written in Python, using
Python’s [unittest] library. Test cases are written as a subclass
of `MarionetteTestCase`, with child tests belonging to instance
methods that have a name starting with `test_`.
You can additionally define [`setUp`] and [`tearDown`] instance
methods to execute code before and after child tests, and
[`setUpClass`]/[`tearDownClass`] for the parent test. When you use
these, it is important to remember calling the `MarionetteTestCase`
superclass’ own [`setUp`]/[`tearDown`] methods since they handle
setup/cleanup of the session.
The test structure is illustrated here:
```python
from marionette_harness import MarionetteTestCase
class TestSomething(MarionetteTestCase):
def setUp(self):
# code to execute before any tests are run
MarionetteTestCase.setUp(self)
def test_foo(self):
# run test for 'foo'
def test_bar(self):
# run test for 'bar'
def tearDown(self):
# code to execute after all tests are run
MarionetteTestCase.tearDown(self)
```
[remote protocol]: Protocol.md
## Test assertions
Assertions are provided courtesy of [unittest]. For example:
```python
from marionette_harness import MarionetteTestCase
class TestSomething(MarionetteTestCase):
def test_foo(self):
self.assertEqual(9, 3 * 3, '3 x 3 should be 9')
self.assertTrue(type(2) == int, '2 should be an integer')
```
## The API
The full API documentation is found [here], but the key objects are:
* `MarionetteTestCase`: a subclass for `unittest.TestCase`
used as a base class for all tests to run.
* {class}`Marionette <marionette_driver.marionette.Marionette>`: client that speaks to Firefox
[here]: /python/marionette_driver.rst