Switch from TSLint to ESLint (typescript-eslint)

.eslintrc.js

@@ -0,0 +1,43 @@
+module.exports = {
+  parser: '@typescript-eslint/parser', // Specifies the ESLint parser
+  extends: [
+    'eslint:recommended',
+    'plugin:react/recommended',
+    'plugin:@typescript-eslint/recommended',
+    'prettier/@typescript-eslint',
+    'plugin:prettier/recommended'
+  ],
+  settings: {
+    react: {
+      version: 'detect'
+    }
+  },
+  env: {
+    browser: true,
+    node: true,
+    es6: true,
+    'jest/globals': true
+  },
+  plugins: ['@typescript-eslint', 'react', 'jest'],
+  parserOptions: {
+    ecmaFeatures: {
+      jsx: true
+    },
+    ecmaVersion: 2018, // Allows for the parsing of modern ECMAScript features
+    sourceType: 'module' // Allows for the use of imports
+  },
+  rules: {
+    'react/prop-types': 'off', // Disable prop-types as we use TypeScript for type checking
+    '@typescript-eslint/explicit-function-return-type': 'off'
+  },
+  overrides: [
+    // Override some TypeScript rules just for .js files
+    {
+      files: ['*.js'],
+
+      rules: {
+        '@typescript-eslint/no-var-requires': 'off' //
+      }
+    }
+  ]
+}

.prettierrc

@@ -1,5 +1,6 @@
 {
   "printWidth": 100,
   "semi": false,
-  "singleQuote": true
+  "singleQuote": true,
+  "tabWidth": 2
 }

README.md

@@ -53,4 +53,4 @@ npm run develop
 ## Tools
 
 - Testing: [Jest](https://jestjs.io) and [react-testing-library](https://github.com/kentcdodds/react-testing-library)
-- Linter: [TSLint](https://palantir.github.io/tslint/) with the `tslint-config-standard` and `tslint-config-prettier` configurations.
+- Linter: [ESLint via typescript-eslint](https://github.com/typescript-eslint/typescript-eslint) with the recommended rules

gatsby-config.js

@@ -1,3 +1,4 @@
+/* eslint-disable @typescript-eslint/camelcase */
 module.exports = {
   siteMetadata: {
     title: 'TypeScript Gatsby Starter',