Add React and TS to webpacker; add react-rails gem

config/webpack/environment.js

@@ -1,6 +1,8 @@
 const { environment } = require('@rails/webpacker')
+const typescript =  require('./loaders/typescript')
 const webpack = require('webpack')
 
+environment.loaders.prepend('typescript', typescript)
 environment.plugins.append(
   'Provide',
   new webpack.ProvidePlugin({

config/webpack/loaders/typescript.js

@@ -0,0 +1,11 @@
+const PnpWebpackPlugin = require('pnp-webpack-plugin')
+
+module.exports = {
+  test: /\.(ts|tsx)?(\.erb)?$/,
+  use: [
+    {
+      loader: 'ts-loader',
+      options: PnpWebpackPlugin.tsLoaderOptions()
+    }
+  ]
+}

config/webpacker.yml

@@ -34,6 +34,9 @@ default: &default
     - .woff2
 
   extensions:
+    - .tsx
+    - .ts
+    - .jsx
     - .mjs
     - .js
     - .sass