Example ESLint file for react

.eslintrc.json

// Need eslint, eslint-plugin-react, eslint-babel installed
{
    "env": {
        "browser": true,
        "commonjs": true,
        "es6": true,
        "node": true
    },
    "parser": "babel-eslint",
    "parserOptions": {
        "ecmaVersion": 7,
        "ecmaFeatures": {
            "jsx": true,
            "modules": true
        },
        "sourceType": "module"
    },
    "rules": {
        "no-const-assign": "warn",
        "no-this-before-super": "warn",
        "no-undef": "warn",
        "no-unreachable": "warn",
        "no-unused-vars": "warn",
        "constructor-super": "warn",
        "valid-typeof": "warn",
        "strict": [2, "never"]
    },
    "plugins": [
        "react"
    ],
    "extends": ["eslint:recommended", "plugin:react/recommended"]
}