webpack/lib/util/createHooksRegistry.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";

/**
 * @template T
 * @param {() => T} createHooks factory that returns a fresh hooks object
 * @returns {(compilation: import("../Compilation")) => T} getter that returns (or creates) hooks for the compilation
 */
const createHooksRegistry = (createHooks) => {
	/** @type {WeakMap<import("../Compilation"), T>} */
	const map = new WeakMap();
	return (compilation) => {
		let hooks = map.get(compilation);
		if (hooks === undefined) {
			// validated once per compilation — this runs on every render and
			// codegen. Matched by class name, not `instanceof`: a compilation from
			// another webpack copy has to pass too, and importing `Compilation`
			// here cycles.
			const candidate =
				/** @type {{ constructor?: { name: string } } | null} */
				(compilation);
			if (
				!candidate ||
				!candidate.constructor ||
				candidate.constructor.name !== "Compilation"
			) {
				throw new TypeError(
					"The 'compilation' argument must be an instance of Compilation"
				);
			}
			hooks = createHooks();
			map.set(compilation, hooks);
		}
		return hooks;
	};
};

module.exports = createHooksRegistry;