pytest-axe

pytest-axe provides a variety of features to simplify accessibility testing using axe-selenium-python.

Requirements

You will need the following prerequisites in order to use pytest-axe:

• Python 2.7 or 3.6
• axe-selenium-python >= 2.1.1
• The appropriate driver for the browser you intend to use, downloaded and added to your path, e.g. geckodriver for Firefox:
  • geckodriver downloaded and added to your PATH

Optional

• pytest-selenium >= 3.0.0

pytest-selenium is required to use the axe pytest fixture.

• PyPOM >= 1.3.0

PyPOM is required to use the run_axe helper method.

Installation

To install pytest-axe:

$ pip install pytest-axe

Usage

pytest-axe adds a command-line option for specifying whether or not to run accessibility tests.

Running pytest with --axe will run only tests marked as accessibility, i.e. @pytest.mark.accessibility.

The absence of this command line option will run only tests not marked as accessibility.

pytest-axe also includes a pytest fixture to handle set up and tear down.

The following example will run aXe-core against the entire page, and check for violations of any impact level.

import pytest

@pytest.mark.nondestructive
def test_header_accessibility(axe):
    violations = axe.run()
    assert len(violations) == 0, axe.report(violations)

You can also customize your accessibility tests by defining context, options, or impact.

import pytest

@pytest.mark.nondestructive
def test_header_accessibility(axe):
    violations = axe.run('header', None, 'critical')
    assert len(violations) == 0, axe.report(violations)

The above example runs aXe against only the content within the <header> tag, and filters for violations labeled critical.

For more information on context and options, view the aXe documentation here.

The third parameter, impact, allows you to filter violations by their impact level. The options are 'critical', 'serious' and 'minor', with the default value set to None.

This will filter violations for the impact level specified, and all violations with a higher impact level.

The axe fixture uses base_url defined in the pytest command or in a config file.

$ pytest --base-url http://www.mozilla.com --driver Firefox test_accessibility.py

Parameterized Tests and Expected Failures

As of version 1.1.0, pytest-axe provides helper methods to generate individual tests for each accessibility rule.

Generating test cases for each accessibility rule enables the ability to mark specific rules as expected failures. To enable test parameterization, parameterized tests should be defined in separate classes, with xfailed rules set in the class-level params dictionary.

Example

PyPOM Example

These examples are dependent on the use of PyPOM , and assumes any Page object has a selenium object attribute.

And with custom run options:

Recording Results

pytest-axe checks for an environment variable ACCESSIBILITY_REPORTING.

To enable writing the aXe JSON results to file, set ACCESSIBILITY_REPORTING=true.

Currently, this will write the JSON files to the root of your test directory, with the page title and a timestamp as the file name.

Resources

• Issue Tracker
• Code
• axe-selenium-python

CHANGELOG

Version 1.1.3

• Modified the way that tests are generated. Rather than configuring xfails in conftest.py, they are defined as class-level variables.

Version 1.1.0

• Added the ability to generate indiviudal test cases for each accessibility rule, which enables xfailing specific accessibility rules.

Version 1.0.0

• Transferred functions and methods from axe_selenium_python.
• run_axe helper method, to simplify accessibility testing for test suites using PyPOM.
• run() method, which injects the aXe JavaScript, runs aXe against the page, filters the results based on a specified impact level, and returns a dictionary of only violations, with the ruleId as the key.
• impact_included, used by run() to filter checks by a specificed impact level.
• Environment variable ACCESSIBILITY_REPORTING to enable recording results.
• analyze(), which calls run() and writes the JSON results to file, if enabled using the environment variable.

Version 0.2.0

• Added a command line argument to filter tests based on the presence or absence of a pytest accessibility marker.