[React] Linting React JSX with ESLint (in ES6)

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-reactpackage.

{
    "rules": {
        "indent": [
            2,
            "tab"
        ],
        "quotes": [
            2,
            "single"
        ],
        "linebreak-style": [
            2,
            "unix"
        ],
        "semi": [
            2,
            "always"
        ],
        "react/prop-types": 1
    },
    "env": {
        "es6": true,
        "browser": true
    },
    "extends": "eslint:recommended",
    "ecmaFeatures": {
        "modules": true,  //es6
        "jsx": true,
        "experimentalObjectRestSpread": true
    },
    "plugins": [
        "react"
    ]
}