Only sync files if explicitly needed by React

Author: CompuIves

packages/app/src/sandbox/eval/transpilers/babel/index.js

@@ -85,6 +85,10 @@ class BabelTranspiler extends WorkerTranspiler {
       const isV7 =
         loaderContext.options.isV7 || isBabel7(dependencies, devDependencies);
 
+      const hasMacros = Object.keys(dependencies).some(
+        d => d.indexOf('macro') > -1
+      );
+
       const babelConfig = getBabelConfig(
         foundConfig || loaderOptions.config,
         loaderOptions,
@@ -104,6 +108,7 @@ class BabelTranspiler extends WorkerTranspiler {
             configs.babelTranspiler.parsed,
           sandboxOptions: configs && configs.sandbox && configs.sandbox.parsed,
           version: isV7 ? 7 : 6,
+          hasMacros,
         },
         loaderContext._module.getId(),
         loaderContext,

packages/app/src/sandbox/eval/transpilers/babel/worker/babel-worker.js

@@ -159,8 +159,8 @@ async function installPreset(Babel, BFSRequire, preset, currentPath, isV7) {
 
 self.importScripts(
   process.env.NODE_ENV === 'development'
-    ? `${process.env.CODESANDBOX_HOST || ''}/static/js/babel.6.26.js`
-    : `${process.env.CODESANDBOX_HOST || ''}/static/js/babel.6.26.min.js`
+    ? `${process.env.CODESANDBOX_HOST || ''}/static/js/babel.7.00-1.min.js`
+    : `${process.env.CODESANDBOX_HOST || ''}/static/js/babel.7.00-1.min.js`
 );
 
 self.postMessage('ready');
@@ -239,6 +239,7 @@ self.addEventListener('message', async event => {
     loaderOptions,
     version,
     type,
+    hasMacros,
   } = event.data;
 
   if (type !== 'compile') {
@@ -253,12 +254,11 @@ self.addEventListener('message', async event => {
 
   if (babelUrl || babelEnvUrl) {
     loadCustomTranspiler(babelUrl, babelEnvUrl);
-  } else if (version === 7) {
+  } else if (version !== 7) {
     loadCustomTranspiler(
       process.env.NODE_ENV === 'development'
-        ? `${process.env.CODESANDBOX_HOST || ''}/static/js/babel.7.00-1.min.js`
-        : `${process.env.CODESANDBOX_HOST ||
-            ''}/static/js/babel.7.00-1.min.js`
+        ? `${process.env.CODESANDBOX_HOST || ''}/static/js/babel.6.26.js`
+        : `${process.env.CODESANDBOX_HOST || ''}/static/js/babel.6.26.min.js`
     );
   }
 
@@ -321,7 +321,9 @@ self.addEventListener('message', async event => {
       flattenedPlugins.indexOf('babel-plugin-macros') > -1 &&
       Object.keys(Babel.availablePlugins).indexOf('babel-plugin-macros') === -1
     ) {
-      await waitForFs();
+      if (hasMacros) {
+        await waitForFs();
+      }
 
       Babel.registerPlugin('babel-plugin-macros', macrosPlugin);
     }