Accessibility Testing Using Nightwatch

Accessibility (A11y) testing is the process of evaluating a web application to ensure that it is usable by people with disabilities. Nightwatch.js, being a powerful testing framework, can be used to automate browser testing, and it can also be used to perform accessibility testing on web applications. In this article, we will explore how to use Nightwatch to perform accessibility testing against web applications using the axeInject() and axeRun() commands.

Before we begin, it's important to note that you will need to have Nightwatch installed on your system. You can do this by running the following command:

npm install nightwatch

Accessibility testing is an important aspect of web development and there are several different accessibility standards and guidelines that should be followed when developing a web application, such as the Web Content Accessibility Guidelines (WCAG) 2.0.

To perform accessibility testing with Nightwatch, you need to first inject the axe-core library into the web application. This can be done using the axeInject() command. Here's an example of how to use the axeInject() command:

module.exports = {
  'Test accessibility': function (browser) {
    browser
      .url('http://example.com')
      .axeInject()
      .end();
  }
};

This test will navigate to the website's home page and inject the axe-core library into the web application.

Once the axe-core library is injected, you can use the axeRun() command to run an accessibility analysis on the current page. Here's an example of how to use the axeRun() command:

module.exports = {
  'Test accessibility': function (browser) {
    browser
      .url('http://example.com')
      .axeInject()
      .axeRun(function(result) {
        console.log(result);
      })
      .end();
  }
};

This test will navigate to the website's home page, inject the axe-core library into the web application, and run an accessibility analysis on the current page. The result will be logged to the console, which contains any accessibility violations found on the page.

You can also use the axeRun() command with options to configure the analysis, for example, you can specify the rules to include or exclude, or the level of accessibility standard to test against.

It's also important to note that accessibility testing should not be limited to automated testing. It's highly recommended to include manual testing by people with disabilities to ensure the best results.

In order to run the test, you can use the following command:

nightwatch tests/accessibility_test.js

This will run the accessibility_test.js file and output the results to the console.

In conclusion, Nightwatch.js can be used to test accessibility against a web application. By using the axe-webdriverjs library and the .analyze() command, you can easily test a web application for accessibility violations and ensure that it is usable by people with disabilities. With the help of this example, you can create your own tests to suit your specific needs and ensure that your application is accessible and compliant with accessibility standards.