refactor: allow requiring modules with no side effects (#17496)

lib/browser/utils.ts

@@ -0,0 +1,38 @@
+import { EventEmitter } from 'events'
+
+/**
+* Creates a lazy instance of modules that can't be required before the
+* app 'ready' event by returning a proxy object to mitigate side effects
+* on 'require'
+*
+* @param {Function} creator - Function that creates a new module instance
+* @param {Object} holder - the object holding the module prototype
+* @param {Boolean} isEventEmitter - whether or not the module is an EventEmitter
+* @returns {Object} - a proxy object for the
+*/
+
+export function createLazyInstance (
+  creator: Function,
+  holder: Object,
+  isEventEmitter: Boolean
+) {
+  let lazyModule: Object
+  const module: any = {}
+  for (const method in (holder as any).prototype) {
+    module[method] = (...args: any) => {
+      // create new instance of module at runtime if none exists
+      if (!lazyModule) {
+        lazyModule = creator()
+        if (isEventEmitter) EventEmitter.call(lazyModule as any)
+      }
+
+      // check for properties on the prototype chain that aren't functions
+      if (typeof (lazyModule as any)[method] !== 'function') {
+        return (lazyModule as any)[method]
+      }
+
+      return (lazyModule as any)[method](...args)
+    }
+  }
+  return module
+}