webpack/lib/dependencies/WebpackMissingModule.js

/*
	MIT License http://www.opensource.org/licenses/mit-license.php
	Author Tobias Koppers @sokra
*/
"use strict";
const toErrorCode = err =>
	`var e = new Error(${JSON.stringify(err)}); e.code = 'MODULE_NOT_FOUND';`;

exports.module = request =>
	`!(function webpackMissingModule() { ${exports.moduleCode(request)} }())`;

exports.promise = request => {
	const errorCode = toErrorCode(`Cannot find module "${request}"`);
	return `Promise.reject(function webpackMissingModule() { ${errorCode} return e; }())`;
};

exports.moduleCode = request => {
	const errorCode = toErrorCode(`Cannot find module "${request}"`);
	return `${errorCode} throw e;`;
};