feat(axe): Add aXe testing library

README.md

@@ -1,8 +1,9 @@
 Accessibility Plugin
 ====================
 
-Protractor comes with support for two accessibility testing options:
+Protractor comes with support for three accessibility testing options:
  * Accessibility Developer Tools
+ * aXe Accessibility Engine
  * Tenon.io
 
 Protractor will run each set of audits (depending on your configuration) on your existing end-to-end
@@ -14,15 +15,18 @@ To understand how each of these tools can be used, see this support matrix:
 
 | Testing Library                      | Pricing                                   | API Key | External Request | No. of Tests | Info                                                                    |
 |--------------------------------------|-------------------------------------------|---------|------------------|--------------|-------------------------------------------------------------------------|
-| Chrome Accessibility Developer Tools | Free                                      | No      | No               | 14           | [Github](https://github.com/GoogleChrome/accessibility-developer-tools) |
-| Tenon.io                             | Free limited accounts, paid subscriptions | Yes     | Yes              | 63           | [Tenon.io](http://tenon.io/)                                            |
+| Chrome Accessibility Developer Tools | Free                                      | No      | No               | 14           | [GitHub](https://github.com/GoogleChrome/accessibility-developer-tools) |
+| aXe Accessibility Engine             | Free                                      | No      | No               | 53           | [GitHub](https://github.com/dequelabs/axe-core/)    
+| Tenon.io                             | Free limited accounts, paid subscriptions | Yes     | Yes              | 63           | [Tenon.io](http://tenon.io/)                                            |                                        |
 
 Protractor now supports the [Accessibility Developer Tools](https://github.com/GoogleChrome/accessibility-developer-tools), the same audit library used by the [Chrome browser extension](https://chrome.google.com/webstore/detail/accessibility-developer-t/fpkknkljclfencbdbgkenhalefipecmb?hl=en). Protractor
 [runs an audit](https://github.com/GoogleChrome/accessibility-developer-tools/wiki/Audit-Rules)
 locally by injecting the Dev Tools script into WebDriver pages, and it can diagnose issues including
 missing labels, incorrect ARIA attributes and color contrast. This is a great starting point if
 you can't send source code over the wire through an API.
 
+[aXe](https://github.com/dequelabs/axe-core) operates similarly to Chrome's Accessibility Developer Tools by injecting axe-core into all frames and checking the content against 53 [accessibility rules](https://github.com/dequelabs/axe-core/blob/master/doc/rule-descriptions.md).
+
 [Tenon.io](http://www.tenon.io) has a more robust set of tests to help you find
 accessibility issues, but it requires [registering](http://tenon.io/register.php) for an API key
 and making an external request for each test, which may not work for everyone. Some people use
@@ -65,6 +69,16 @@ Enable this plugin in your config file:
       }]
     }
 ```
+```js
+  // aXe only:
+  exports.config = {
+      ...
+      plugins: [{
+        axe: true,
+        package: 'protractor-accessibility-plugin'
+      }]
+    }
+```
 ```js
   // Tenon.io only:
   exports.config = {

index.js

@@ -3,6 +3,7 @@ var q = require('q'),
     path = require('path'),
     _ = require('lodash'),
     request = require('request'),
+    AxeBuilder = require('axe-webdriverjs'),
     Entities = require('html-entities').XmlEntities;
 
 /**
@@ -57,6 +58,10 @@ function teardown() {
 
   var audits = [];
 
+  if (this.config.axe) {
+    audits.push(runAxe(this));
+  }
+
   if (this.config.chromeA11YDevTools) {
     audits.push(runChromeDevTools(this));
   }
@@ -226,6 +231,54 @@ function runChromeDevTools(context) {
       });
     });
   });
+
+}
+
+/**
+ * Audits page source against aXe: https://github.com/dequelabs/axe-core
+ *
+ * @param {Object} context The plugin context object
+ * @return {q.Promise} A promise which resolves when the audit is finished
+ * @private
+ */
+function runAxe(context) {
+
+  var deferred = q.defer();
+
+  AxeBuilder(browser.driver)
+    .analyze(function(results) {
+      deferred.resolve(results);
+    });
+
+  return deferred.promise.then(function(results) {
+    return processAxeResults(results);
+  });
+
+  function processAxeResults(results) {
+
+    var testHeader = 'aXe - '
+
+    var numResults = results.violations.length;
+
+    if (numResults === 0) {
+      return context.addSuccess();
+    }
+
+    results.passes.forEach(function(result) {
+      context.addSuccess({specName: testHeader + result.help});
+    });
+
+    return results.violations.forEach(function(result) {
+      var label = result.nodes.length === 1 ? ' element ' : ' elements ';
+      var msg = result.nodes.reduce(function(msg, node) {
+        return msg + '\t\t' + node.html + '\n';
+      }, '\n');
+      msg = '\n\t\t' + result.nodes.length + label + 'failed:' + msg + '\n\n\t\t' + result.helpUrl
+      context.addFailure(msg, {specName: testHeader + result.help});
+    });
+
+  }
+
 }
 
 // Export

package.json

@@ -29,6 +29,8 @@
   "homepage": "https://github.com/angular/protractor-accessibility-plugin",
   "dependencies": {
     "accessibility-developer-tools": "^2.9.0-rc.0",
+    "axe-core": "^2.0.5",
+    "axe-webdriverjs": "^0.2.0",
     "html-entities": "^1.2.0",
     "lodash": "^3.10.1",
     "q": "^1.4.1",

spec/failureConfig.js

@@ -16,6 +16,7 @@ exports.config = {
     chromeA11YDevTools: {
       treatWarningsAsFailures: true
     },
+    axe: true,
     path: '../index.js'
   }]
 };

test.js

@@ -26,6 +26,15 @@ executor.addCommandlineTest(
     {
       message: '1 element failed:'
     },
+    {
+      message: '1 element failed:'
+    },
+    {
+      message: '3 elements failed:'
+    },
+    {
+      message: '1 element failed:'
+    },
     {
       message: '1 element failed:'
     }]);