Learn Eslint, Riot and Webstorm

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Our first layer of defense when building accessible React applications is to add some auditing tools to our development workflow. This should include adding static analysis checking for common accessibility standards and best practices. We can get this with the latest eslint plugin: "eslint-plugin-jsx-a11y". If you are already linting your projects adding this plugin should fit very smoothly into your workflow.

## Resources
1. [List of all the rules supported by eslint-plugin-jsx-a11y](https://github.com/evcohen/eslint-plugin-jsx-a11y#supported-rules)
2. [Comparison of the difference in rules between recommended and strict mode](https://github.com/evcohen/eslint-plugin-jsx-a11y#difference-between-recommended-and-strict-mode)
3. [Background on how the Accessibility API implemented by browsers interfaces with Assistive Technologies](https://github.com/evcohen/eslint-plugin-jsx-a11y#some-background-on-wai-aria-the-ax-tree-and-browsers)

Set up ESLint to Audit Accessibility Issues in React

The pluggable linting utility for JavaScript and JSX.

eslint

We have a number of options to use when testing for accessibility issues concerning alternative text for images.  The react-axe library and axe browser extension will both report when an image is missing alternative text.  The tota11y browser extension will annotate any images that are missing alternative text.  Running eslint with the eslint-plugin-jsx-a11y plugin installed will report on any `<img>` elements missing an `alt` attribute.  Finally, we can use a screen reader to actually hear what is read when an image has focus.

Test for Image Alternative Text Accessibility Issues

Images must have text alternatives that describe the information or function 
represented by them so they can be read and understood by those using screen readers.

## Alternative text for images
* All `<img>` elements should have an `alt` attribute provided
    * When not provided many screen readers will fallback to reading the file name instead
* The `alt` value should not include words like _“image”_, _“picture”_ or _“icon”_
    * Screen readers are already announcing that the element is an image
* Images that are decorative only and provide no information or function to the page should be hidden from Assistive Technologies by providing an empty `alt` attribute (`alt=””`)

## References
* https://www.w3.org/WAI/tutorials/images/
* https://www.w3.org/WAI/tutorials/images/decision-tree/
* https://www.w3.org/WAI/tutorials/images/tips/
* https://www.w3.org/WAI/tutorials/images/informative/
* https://www.w3.org/WAI/tutorials/images/functional/
* https://www.w3.org/WAI/tutorials/images/textual/

Define Images with Appropriate Text Alternatives

Our accessibility auditing toolkit makes it very easy for us to test for any form controls that are missing labels or are not correctly associated with their labels.  Running Eslint with the eslint-plugin-jsx-a11y installed will show us any form controls with missing or unassociated labels.  Running react-axe or using axe to audit a web page will similarly list any of these findings.  Finally using tota11y we can annotate any form controls on a page that are missing labels.  This is definitely some of the lower hanging fruit that we can easily find and fix when making our applications accessible!

Test for Form Control Label Accessibility Issues

Labeling inputs, elements, and widgets add context and clarity for assistive technology such as screen readers.  Elements of a `<form>` such as `<input>` or `<textarea>` or `<select>` should be labelled by using a `<label>` element.  Placeholder text can be used in addition to a label but should not be used in place of a label as not all assistive technologies respect placeholder text.

Ensure Form Controls have Accessible Labels

JavaScript® (often shortened to JS) is a lightweight, interpreted, object-oriented language with first-class functions, most known as the scripting language for Web pages, but used in many non-browser environments as well such as node.js or Apache CouchDB. It is a prototype-based, multi-paradigm scripting language that is dynamic, and supports object-oriented, imperative, and functional programming styles.

javascript

In this lesson you will learn how to use the eslint yeoman generator to scaffold a new plugin to provide custom rules for your project. 
You will also be able to check the basic skeleton for an eslint ruleand a working example rule to apply a naming convention for async functions.

Scaffold an eslint Plugin with Yeoman

Nx already comes with a default TypeScript setup. Although you can opt-out of that and generate plain JS based components, especially in a large setup TypeScript can be beneficial in uncovering potential issues early. To add an extra level, Nx also comes with preconfigured eslint for all the apps and libraries. In this lesson we're going to explore the lint setup and how it can be used.

Linting a React app with Nx

When exploring a new framework or technology, it is nice to have a seed project or sandbox so you can just get in and start playing. Let's build our React playground using npm, browserify, 6to5, and more within WebStorm!

Setting up a React Playground Dev Environment

Lightweight yet powerful IDE, perfectly equipped for complex client-side development and server-side development with Node.js.

webstorm

John Lindquist is a WebStorm wizard. In this lesson, he'll show you some of the tips & tricks he uses to squeeze maximum productivity out of his tool of choice. 

Tips & Tricks

Riot brings custom tags to all modern browsers. Think React + Polymer but with enjoyable syntax and a small learning curve.

riot

Tag Options allow you to abstract your custom tag elements into reusable objects by allowing the tag-user to specify the dynamic parameters of their component.

Riot JS - Tag Options

Getting started with Riot JS. We'll discuss riot's compile and mount process and build a small hello world component with simple data-binding.

Riot JS - Getting Started with this React-like micro-library

Riot can listen for raw dom events on any element by adding the on* attribute to elements and referencing an event handler. Let's walk through a couple examples.

Riot JS - DOM Events

You can easily share your code from WebStorm with others using the "Create Gist" feature. This lesson walks you through how to create a gist from a single or multiples files and also how to use gist.run to share a running version of your code

WebStorm - Sharing a Gist

ESLint is a JavaScript linter (static analysis tool) that offers full support for ES6, JSX, and other modern tools via plugins. We walk through setting up ESLint in a project, using the `eslint --init` CLI tool with the JSX and ES6 options, writing a React component in JSX, and adding some extra react linting rules with a plugin. ESLint is built to be "pluggable" with simple, extendable, modular rules and an API for writing and using plugins. ESLint has many rules which are all turned off by default; you can extend the core "recommended" rules which will catch common JavaScript errors, and you can also turn on stylistic rules for code consistency. You can also use plugin rules which we do in this lesson with the `eslint-plugin-react` package.

Linting React JSX with ESLint (in ES6)

It's easy to repeat over a collection and render many elements. Riot works very similar to Angular and has various syntaxes for it's each attribute. We'll look at the typical syntax for arrays, a shortened syntax, and an object key/value syntax.

Riot JS - Repeating Elements with Each Attribute

WebStorm can save you tons of time by managing your imports for you. John walks you through a few key WebStorm importing tips to help speed up your importing workflow.

WebStorm - Managing Imports

A quick tutorial covering installing Karma and running tests from the command line and Webstorm.

Introduction to Karma

AngularJS is an open-source JavaScript framework, maintained by Google, that assists with running single-page applications. Its goal is to augment web-based applications with model–view–controller (MVC) capability, in an effort to make both development and testing easier.

angularjs

In this lesson John shows some tricks for speeding up your test suite. He digs into some handy features of WebStorm, including the *ddescriber* plugin, as well as some alternative methods for Jasmine for selectively running your tests.

Speed Testing with WebStorm and Jasmine

Nuclide is the IDE Facebook employees use to write React code. But setting it up to use Flow type checking and Eslint to lint files on the fly is tricky. This video shows you how. 

Setup Nuclide to use Flow and Eslint (Mac)

Riot takes a 'keep your styles close' approach with custom tags. You are encouraged to place your styles for a tags element right inline with the html and javascript. Learn how riot parses the inline styles as well as ways to keep your styles from bleeding out to the rest of your app. Scoped styles provide great isolation for your custom tag. Use the class attribute's special binding syntax to easily add and remove a class based on an expression.

Riot JS - Scoped CSS and Toggled Classes

In this lesson, we'll walk through installing a custom color scheme into our [WebStorm](https://www.jetbrains.com/webstorm/) IDE. Dayle Rees's [daylerees/colour-schemes](https://github.com/daylerees/colour-schemes/blob/master/jetbrains/peacocks-in-space.icls) has a great collection of themes ready to install in different formats for various editors.

For this example, we will install the [Peacocks In Space](https://github.com/daylerees/colour-schemes/blob/master/jetbrains/peacocks-in-space.icls) theme into an OS X [WebStorm 11 EAP](https://confluence.jetbrains.com/display/WI/WebStorm+EAP) installation. _Note: This process will be very similar (or identical) for previous versions of WebStorm and other editors in the [JetBrain's family of editors](https://www.jetbrains.com/)._

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