webpack/lib/prefetch/ChunkPrefetchFunctionRuntimeModule.js

Packs ECMAScript/CommonJs/AMD modules for the browser. Allows you to split your codebase into multiple bundles, which can be loaded on demand. Supports loaders to preprocess files, i.e. json, jsx, es7, css, less, ... and your custom stuff.

/*
	MIT License http://www.opensource.org/licenses/mit-license.php
*/

"use strict";

const RuntimeModule = require("../RuntimeModule");
const Template = require("../Template");

/** @typedef {import("../Compilation")} Compilation */

class ChunkPrefetchFunctionRuntimeModule extends RuntimeModule {
	/**
	 * @param {"prefetch" | "preload"} type "prefetch" or "preload" chunk type function
	 * @param {string} runtimeFunction the runtime function name
	 * @param {string} runtimeHandlers the runtime handlers
	 */
	constructor(type, runtimeFunction, runtimeHandlers) {
		super(`chunk ${type} function`);
		this.runtimeFunction = runtimeFunction;
		this.runtimeHandlers = runtimeHandlers;
	}

	/**
	 * @returns {string | null} runtime code
	 */
	generate() {
		const { runtimeFunction, runtimeHandlers } = this;
		const compilation = /** @type {Compilation} */ (this.compilation);
		const { runtimeTemplate } = compilation;
		return Template.asString([
			`${runtimeHandlers} = {};`,
			`${runtimeFunction} = ${runtimeTemplate.basicFunction("chunkId", [
				// map is shorter than forEach
				`Object.keys(${runtimeHandlers}).map(${runtimeTemplate.basicFunction(
					"key",
					`${runtimeHandlers}[key](chunkId);`
				)});`
			])}`
		]);
	}
}

module.exports = ChunkPrefetchFunctionRuntimeModule;