feat: add @axe-core/puppeteer (#7)

.circleci/config.yml

@@ -30,21 +30,29 @@ jobs:
       - restore_cache:
           keys:
             - v1-cli-npm-{{ checksum "packages/cli/package-lock.json" }}
+      - restore_cache:
+          keys:
+            - v1-puppeteer-npm-{{ checksum "packages/puppeteer/package-lock.json" }}
       - run: npm ci
       - save_cache:
           key: v1-root-npm-{{ checksum "package-lock.json" }}
           paths:
             - node_modules
       - run: npm run bootstrap
       - save_cache:
-          key: v1-npm-cache-{{ .Environment.CIRCLE_SHA1 }}
+          key: v1-cli-npm-{{ checksum "packages/cli/package-lock.json" }}
           paths:
-            - node_modules
             - packages/cli/node_modules
       - save_cache:
-          key: v1-cli-npm-{{ checksum "packages/cli/package-lock.json" }}
+          key: v1-puppeteer-npm-{{ checksum "packages/puppeteer/package-lock.json" }}
+          paths:
+            - packages/puppeteer/node_modules
+      - save_cache:
+          key: v1-npm-cache-{{ .Environment.CIRCLE_SHA1 }}
           paths:
+            - node_modules
             - packages/cli/node_modules
+            - packages/puppeteer/node_modules
 
   lint:
     <<: *defaults
@@ -60,6 +68,14 @@ jobs:
       - restore_dependency_cache
       - run: npm run test --prefix=packages/cli
 
+  puppeteer:
+    <<: *defaults
+    steps:
+      - checkout
+      - restore_dependency_cache
+      - run: npm run build --prefix=packages/puppeteer
+      - run: npm run coverage --prefix=packages/puppeteer
+
 workflows:
   version: 2
   build_and_test:
@@ -71,3 +87,6 @@ workflows:
       - cli:
           requires:
             - lint
+      - puppeteer:
+          requires:
+            - lint

.github/axe-linter.yml

@@ -0,0 +1,3 @@
+rules:
+  # Disables a11y issues for testing
+  html-has-lang: false 

packages/puppeteer/README.md

@@ -0,0 +1,197 @@
+# @axe-core/puppeteer
+
+Provides a chainable axe API for Puppeteer and automatically injects into all frames.
+
+Previous versions of this program were maintained at [dequelabs/axe-puppeteer](https://github.com/dequelabs/axe-puppeteer).
+
+## Getting Started
+
+Install [Node.js](https://docs.npmjs.com/getting-started/installing-node) if you haven't already. For running axe-puppeteer tests read more about [setting up your environment](CONTRIBUTING.md).
+
+Install Puppeteer: `npm install puppeteer --no-save`
+
+Install axe-puppeteer and its dependencies: `npm install @axe-core/puppeteer`
+
+## Usage
+
+This module uses a chainable API to assist in injecting, configuring and analyzing using axe with Puppeteer. As such, it is required to pass an instance of a Puppeteer `Page` or `Frame`.
+
+Here is an example of a script that will drive Puppeteer to this repository, perform analysis and then log results to the console.
+
+```js
+const { AxePuppeteer } = require('@axe-core/puppeteer');
+const puppeteer = require('puppeteer');
+
+(async () => {
+  const browser = await puppeteer.launch();
+  const page = await browser.newPage();
+  await page.setBypassCSP(true);
+
+  await page.goto('https://dequeuniversity.com/demo/mars/');
+
+  const results = await new AxePuppeteer(page).analyze();
+  console.log(results);
+
+  await page.close();
+  await browser.close();
+})();
+```
+
+Note: Usage examples make use of ES2017 async/await. Use of `await` can only be done in a function
+declared `async`. If your project does not support async/await, you can just directly use the promise
+`async` functions return. [Check here for more
+information.](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/async_function)
+
+## Bypassing Content Security Policy
+
+When trying to run axe, you might run into issues if the page you are checking has Content Security Policy enabled. To get around this, you must disable it through `Page#setBypassCSP` **before** navigating to the site.
+
+### loadPage(browser: Browser, url: string, { opts, source }: { opts?: any, source?: string } = {})
+
+An alternate constructor is available which opens a page and performs the CSP bypass for you.
+
+It closes the page after `analyze` is called.
+
+```js
+const { loadPage } = require('@axe-core/puppeteer');
+const puppeteer = require('puppeteer');
+
+(async () => {
+  const browser = await puppeteer.launch();
+  const axeBuilder = await loadPage(
+    browser,
+    'https://dequeuniversity.com/demo/mars/'
+  );
+  const results = await axeBuilder.analyze();
+  console.log(results);
+
+  await browser.close();
+})();
+```
+
+### AxePuppeteer(page: Frame | Page[, axeSource: string])
+
+Constructor for the AxePuppeteer helper.
+You must pass an instance of a Puppeteer `Frame` or `Page` as the first argument. Cannot be called without the `new` keyword.
+
+```js
+const builder = new AxePuppeteer(page);
+```
+
+If you wish to run a specific version of axe-core, you can pass the source `axe-core` source file in as a string. Doing so will mean axe-puppeteer runs this version of axe-core, instead of the one installed as a dependency of axe-puppeteer.
+
+```js
+const axeSource = fs.readFileSync('./axe-3.0.js', 'utf8');
+const builder = new AxePuppeteer(page, axeSource);
+```
+
+Note that you might need to bypass the Content Security Policy in some cases.
+
+### AxePuppeteer#include(selector: string | string[])
+
+Adds a CSS selector to the list of elements to include in analysis
+
+```js
+new AxePuppeteer(page).include('.results-panel');
+```
+
+### AxePuppeteer#exclude(selector: string | string[])
+
+Add a CSS selector to the list of elements to exclude from analysis
+
+```js
+new AxePuppeteer(page).include('.results-panel').exclude('.results-panel h2');
+```
+
+### AxePuppeteer#options(options: Axe.RunOptions)
+
+Specifies options to be used by `axe.run`. **Will override any other configured options, including calls to `withRules` and `withTags`.**
+See [axe-core API documentation](https://github.com/dequelabs/axe-core/blob/master/doc/API.md)
+for information on its structure.
+
+```js
+new AxePuppeteer(page).options({
+  checks: { 'valid-lang': ['orcish'] }
+});
+```
+
+### AxePuppeteer#withRules(rules: string | string[])
+
+Limits analysis to only those with the specified rule IDs. Accepts a String of a single rule ID or an Array of multiple rule IDs. **Subsequent calls to `AxePuppeteer#options`, `AxePuppeteer#withRules` or `AxePuppeteer#withRules` will override specified options.**
+
+```js
+new AxePuppeteer(page).withRules('html-lang');
+```
+
+```js
+new AxePuppeteer(page).withRules(['html-lang', 'image-alt']);
+```
+
+### AxePuppeteer#withTags(tags: string | string[])
+
+Limits analysis to only those with the specified rule IDs. Accepts a String of a single tag or an Array of multiple tags. **Subsequent calls to `AxePuppeteer#options`, `AxePuppeteer#withRules` or `AxePuppeteer#withRules` will override specified options.**
+
+```js
+new AxePuppeteer(page).withTags('wcag2a');
+```
+
+```js
+new AxePuppeteer(page).withTags(['wcag2a', 'wcag2aa']);
+```
+
+### AxePuppeteer#disableRules(rules: string | string[])
+
+Skips verification of the rules provided. Accepts a String of a single rule ID or an Array of multiple rule IDs. **Subsequent calls to `AxePuppeteer#options`, `AxePuppeteer#disableRules` will override specified options.**
+
+```js
+new AxePuppeteer(page).disableRules('color-contrast');
+```
+
+or use it combined with some specified tags:
+
+```js
+new AxePuppeteer(page)
+  .withTags(['wcag2a', 'wcag2aa'])
+  .disableRules('color-contrast');
+```
+
+### AxePuppeteer#configure(config: Axe.Spec)
+
+Inject an axe configuration object to modify the ruleset before running Analyze. Subsequent calls to this method will invalidate previous ones by calling `axe.configure` and replacing the config object. See [axe-core API documentation](https://github.com/dequelabs/axe-core/blob/master/doc/API.md#api-name-axeconfigure) for documentation on the object structure.
+
+```js
+const config = {
+  checks: [Object],
+  rules: [Object]
+};
+const results = await new AxePuppeteer(page).configure(config).analyze();
+console.log(results);
+```
+
+### AxePuppeteer#analyze([callback: (Error | null[, Object]) => void])
+
+Performs analysis and passes any encountered error and/or the result object to the provided callback function or promise function. **Does not chain as the operation is asynchronous**
+
+Using the returned promise (optional):
+
+```js
+new AxePuppeteer(page)
+  .analyze()
+  .then(function (results) {
+    console.log(results);
+  })
+  .catch(err => {
+    // Handle error somehow
+  });
+```
+
+Using a callback function
+
+```js
+new AxePuppeteer(page).analyze(function (err, results) {
+  if (err) {
+    // Handle error somehow
+  }
+  console.log(results);
+});
+```