[RFC] perf: use an internal module resolver to improve require performance (#14633)

* perf: use an internal module resolver instead of relative requires

* perf: memoize the results of getting exported Electron properties

* perf: make internal module changes consistent across sandboxed / bundled files

lib/common/api/exports/electron.js

@@ -1,13 +1,29 @@
-const moduleList = require('../module-list')
+const moduleList = require('@electron/internal/common/api/module-list')
 
-// Attaches properties to |exports|.
-exports.defineProperties = function (exports) {
+exports.memoizedGetter = (getter) => {
+  /*
+   * It's ok to leak this value as it would be leaked by the global
+   * node module cache anyway at `Module._cache`.  This memoization
+   * is dramatically faster than relying on nodes module cache however
+   */
+  let memoizedValue = null
+
+  return () => {
+    if (memoizedValue === null) {
+      memoizedValue = getter()
+    }
+    return memoizedValue
+  }
+}
+
+// Attaches properties to |targetExports|.
+exports.defineProperties = function (targetExports) {
   const descriptors = {}
   for (const module of moduleList) {
     descriptors[module.name] = {
       enumerable: !module.private,
-      get: () => require(`../${module.file}`)
+      get: exports.memoizedGetter(() => require(`@electron/internal/common/api/${module.file}`))
     }
   }
-  return Object.defineProperties(exports, descriptors)
+  return Object.defineProperties(targetExports, descriptors)
 }

lib/common/init.js

@@ -1,7 +1,7 @@
 const timers = require('timers')
 const util = require('util')
 
-process.atomBinding = require('./atom-binding-setup')(process.binding, process.type)
+process.atomBinding = require('@electron/internal/common/atom-binding-setup')(process.binding, process.type)
 
 // setImmediate and process.nextTick makes use of uv_check and uv_prepare to
 // run the callbacks, however since we only run uv loop on requests, the

lib/common/reset-search-paths.js

@@ -24,6 +24,9 @@ Module._nodeModulePaths = function (from) {
   }
 }
 
+const BASE_INTERNAL_PATH = path.resolve(__dirname, '..')
+const INTERNAL_MODULE_PREFIX = '@electron/internal/'
+
 // Patch Module._resolveFilename to always require the Electron API when
 // require('electron') is done.
 const electronPath = path.join(__dirname, '..', process.type, 'api', 'exports', 'electron.js')
@@ -31,6 +34,9 @@ const originalResolveFilename = Module._resolveFilename
 Module._resolveFilename = function (request, parent, isMain) {
   if (request === 'electron') {
     return electronPath
+  } else if (request.startsWith(INTERNAL_MODULE_PREFIX) && request.length > INTERNAL_MODULE_PREFIX.length) {
+    const slicedRequest = request.slice(INTERNAL_MODULE_PREFIX.length)
+    return path.resolve(BASE_INTERNAL_PATH, `${slicedRequest}${slicedRequest.endsWith('.js') ? '' : '.js'}`)
   } else {
     return originalResolveFilename(request, parent, isMain)
   }