If you’re a developer looking to build accessibility assertions into your own testing tool, there are a few things you’ll want to look for:
- A standalone library that you can run in development and CI.
- Open source, for its transparency and flexibility
Here I’ve listed three libraries that meet the above criteria, along with some of the finer points about the tools, including license, standards covered, unit test coverage, and documentation detail.
Tests map discretely to standardized guidelines
Test result objects have clear descriptions
No unit or behavioral tests
Accessibility Developer Tools
Accessibility Developer Tools is available bundled as a Chrome Extension.
Robust consideration of WAI-ARIA techniques
Good unit test coverage
Finding associated WCAG standards is an extra step away
Quail is MIT licensed, with a set of assertions that are well tested and have a clear mapping to WCAG 1.0 and 2.0 standards as well as Section 508 rules. It is a comprehensive and well documented library. Its biggest drawback is that it does not have a browser based extension or plugin, and that makes it harder to evaluate out of the box.
No associated plugin or extension
Whatever you decide on, keep in mind that automated accessibility testing is never a complete picture of accessibility. Make sure to smoke test with screen readers and keyboard navigation, and present the app to folks with disabilities and see what works (and what doesn’t).