Fix hanging start

redbugz · redbugz · commit 46c8d947c7d6 · 2019-04-26T21:04:21.000-06:00
CRA 3 opts-in to a new webpack 5 feature early to save memory: `futureEmitAssets` facebook#6696 This optimization only stores the file sizes during webpack compilation, no longer storing the original source webpack/webpack#8642 This is incompatible with our webpack-dev-server customization setting of `writeToDisk` webpack/webpack#8642 (comment) which tries to read the source after emit, which throws an exception, but that error is swallowed and the `npm start` just hangs. Before we update to webpack 5, where this feature will be the default, we need to stop writing to disk, or find another way to do it than the `writeToDisk` flag.
diff --git a/packages/react-scripts/config/webpack.config.js b/packages/react-scripts/config/webpack.config.js
@@ -173,7 +173,8 @@ module.exports = function(webpackEnv) {
         ? 'static/js/[name].[contenthash:8].js'
         : isEnvDevelopment && 'static/js/bundle.js',
       // TODO: remove this when upgrading to webpack 5
-      futureEmitAssets: true,
+      // FS - writeToDisk and futureEmitAssets are not compatible, so defaulting back to false: https://github.com/webpack/webpack/pull/8642#issuecomment-455342804
+      futureEmitAssets: false,
       // There are also additional JS chunk files if you use code splitting.
       chunkFilename: isEnvProduction
         ? 'static/js/[name].[contenthash:8].chunk.js'
