source: trip-planner-front/node_modules/webpack/lib/serialization/PlainObjectSerializer.js

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

"use strict";

const cache = new WeakMap();

class ObjectStructure {
        constructor() {
                this.keys = undefined;
                this.children = undefined;
        }

        getKeys(keys) {
                if (this.keys === undefined) this.keys = keys;
                return this.keys;
        }

        key(key) {
                if (this.children === undefined) this.children = new Map();
                const child = this.children.get(key);
                if (child !== undefined) return child;
                const newChild = new ObjectStructure();
                this.children.set(key, newChild);
                return newChild;
        }
}

const getCachedKeys = (keys, cacheAssoc) => {
        let root = cache.get(cacheAssoc);
        if (root === undefined) {
                root = new ObjectStructure();
                cache.set(cacheAssoc, root);
        }
        let current = root;
        for (const key of keys) {
                current = current.key(key);
        }
        return current.getKeys(keys);
};

class PlainObjectSerializer {
        serialize(obj, { write }) {
                const keys = Object.keys(obj);
                if (keys.length > 128) {
                        // Objects with so many keys are unlikely to share structure
                        // with other objects
                        write(keys);
                        for (const key of keys) {
                                write(obj[key]);
                        }
                } else if (keys.length > 1) {
                        write(getCachedKeys(keys, write));
                        for (const key of keys) {
                                write(obj[key]);
                        }
                } else if (keys.length === 1) {
                        const key = keys[0];
                        write(key);
                        write(obj[key]);
                } else {
                        write(null);
                }
        }
        deserialize({ read }) {
                const keys = read();
                const obj = {};
                if (Array.isArray(keys)) {
                        for (const key of keys) {
                                obj[key] = read();
                        }
                } else if (keys !== null) {
                        obj[keys] = read();
                }
                return obj;
        }
}

module.exports = PlainObjectSerializer;