add "babel-plugin-transform-decorators-legacy": "^1.3.4"

Author: zangrafx

Diff for: packages/react-scripts/config/webpack.config.dev.js

@@ -192,6 +192,11 @@ module.exports = {
           // @remove-on-eject-begin
           babelrc: false,
           presets: [require.resolve('babel-preset-react-app')],
+          plugins: [
+            // require.resolve('babel-plugin-transform-class-properties'),
+            // this enables decorators
+            require.resolve('babel-plugin-transform-decorators-legacy'),
+          ],
           // @remove-on-eject-end
           // This is a feature of `babel-loader` for webpack (not Babel itself).
           // It enables caching results in ./node_modules/.cache/babel-loader/

Diff for: packages/react-scripts/config/webpack.config.prod.js

@@ -189,7 +189,15 @@ module.exports = {
         // @remove-on-eject-begin
         options: {
           babelrc: false,
-          presets: [require.resolve('babel-preset-react-app')],
+          presets: [
+            require.resolve('babel-preset-react-app'),
+            // this might be needed if babel-preset-react-app is missing new features we use
+            // require.resolve('babel-preset-stage-2')
+          ],
+          plugins: [
+            // this enables decorators
+            require.resolve('babel-plugin-transform-decorators-legacy'),
+          ],
         },
         // @remove-on-eject-end
       },

Diff for: packages/react-scripts/package.json

@@ -26,6 +26,7 @@
     "babel-eslint": "7.2.3",
     "babel-jest": "20.0.3",
     "babel-loader": "7.0.0",
+    "babel-plugin-transform-decorators-legacy": "^1.3.4",
     "babel-preset-react-app": "^3.0.0",
     "babel-runtime": "6.23.0",
     "case-sensitive-paths-webpack-plugin": "1.1.4",