source: frontend/node_modules/webpack/lib/ids/HashedModuleIdsPlugin.js

/*
        MIT License http://www.opensource.org/licenses/mit-license.php
        Author Tobias Koppers @sokra
*/

"use strict";

const { DEFAULTS } = require("../config/defaults");
const {
        compareModulesByPreOrderIndexOrIdentifier
} = require("../util/comparators");
const createHash = require("../util/createHash");
const {
        getFullModuleName,
        getUsedModuleIdsAndModules
} = require("./IdHelpers");

/** @typedef {import("../../declarations/plugins/ids/HashedModuleIdsPlugin").HashedModuleIdsPluginOptions} HashedModuleIdsPluginOptions */
/** @typedef {import("../Compiler")} Compiler */

const PLUGIN_NAME = "HashedModuleIdsPlugin";

class HashedModuleIdsPlugin {
        /**
         * Creates an instance of HashedModuleIdsPlugin.
         * @param {HashedModuleIdsPluginOptions=} options options object
         */
        constructor(options = {}) {
                /** @type {HashedModuleIdsPluginOptions} */
                this.options = options;
        }

        /**
         * Applies the plugin by registering its hooks on the compiler.
         * @param {Compiler} compiler the compiler instance
         * @returns {void}
         */
        apply(compiler) {
                compiler.hooks.validate.tap(PLUGIN_NAME, () => {
                        compiler.validate(
                                () => require("../../schemas/plugins/ids/HashedModuleIdsPlugin.json"),
                                this.options,
                                {
                                        name: "Hashed Module Ids Plugin",
                                        baseDataPath: "options"
                                },
                                (options) =>
                                        require("../../schemas/plugins/ids/HashedModuleIdsPlugin.check")(
                                                options
                                        )
                        );
                });
                compiler.hooks.compilation.tap(PLUGIN_NAME, (compilation) => {
                        compilation.hooks.moduleIds.tap(PLUGIN_NAME, () => {
                                const chunkGraph = compilation.chunkGraph;
                                const context = this.options.context
                                        ? this.options.context
                                        : compiler.context;

                                const [usedIds, modules] = getUsedModuleIdsAndModules(compilation);
                                const modulesInNaturalOrder = modules.sort(
                                        compareModulesByPreOrderIndexOrIdentifier(compilation.moduleGraph)
                                );
                                for (const module of modulesInNaturalOrder) {
                                        const ident = getFullModuleName(module, context, compiler.root);
                                        const hash = createHash(
                                                this.options.hashFunction || DEFAULTS.HASH_FUNCTION
                                        );
                                        hash.update(ident || "");
                                        const hashId = hash.digest(this.options.hashDigest || "base64");
                                        let len = this.options.hashDigestLength || 4;
                                        while (usedIds.has(hashId.slice(0, len))) {
                                                /** @type {number} */ (len)++;
                                        }
                                        const moduleId = hashId.slice(0, len);
                                        chunkGraph.setModuleId(module, moduleId);
                                        usedIds.add(moduleId);
                                }
                        });
                });
        }
}

module.exports = HashedModuleIdsPlugin;