Remove explicit react-hot-loader logic

We should not support it since by default it's an aggressive and flaky
HMR handler. Where it says it can handle more file changes than it
actually can. Developers usually learn not to trust it and refresh
manually.

It also breaks JS error handling in arrow functions:

gaearon/react-proxy#76

After this change, HMR is still properly configured, including the
module.hot api and client/server communications. By default JS changes
refresh and CSS changes appear without refresh.

For the future, we should monitor the progress of this PR:

facebook/create-react-app#2304

shared/gulpfile.js

@@ -31,11 +31,6 @@ const babel = target =>
       'react',
       ['es2015', { modules: target === 'es2015' ? false : 'commonjs' }],
     ],
-    env: {
-      development: {
-        plugins: [require.resolve('react-hot-loader/babel')],
-      },
-    },
   }).on('error', function(error) {
     // only log babel errors once.
     if (target === 'es2015') {

utilities/neutrino-preset-tux/package.json

@@ -21,6 +21,7 @@
     "neutrino-middleware-banner": "^6.1.5",
     "neutrino-middleware-compile-loader": "^6.1.5",
     "neutrino-middleware-env": "^6.1.5",
+    "neutrino-middleware-hot": "^6.1.5",
     "neutrino-preset-react": "6.1.5",
     "react-dev-utils": "~4.0.1",
     "react-error-overlay": "~2.0.1",

utilities/neutrino-preset-tux/src/index.ts

@@ -1,6 +1,7 @@
 import { Neutrino } from 'neutrino'
 import merge from 'deepmerge'
 import react from 'neutrino-preset-react'
+import hot from 'neutrino-middleware-hot'
 import {
   env,
   ssr,
@@ -46,7 +47,12 @@ export default (neutrino: Neutrino, opts: Partial<Options> = {}) => {
     : neutrino.options.browserEntry
 
   // Build on top of the offical react preset (overriding open functionality).
-  neutrino.use(react, merge<any>(options, { devServer: { open: false } }))
+  // Skip react-hot-loader for now while enabling other HMR functionality.
+  neutrino.use(
+    react,
+    merge<any>(options, { devServer: { open: false }, hot: false })
+  )
+  neutrino.use(hot)
 
   // Switch to custom html plugin.
   neutrino.use(html, options.html)