import uhyphen from 'uhyphen'; import {setPrototypeOf} from '../shared/object.js'; const refs = new WeakMap; const key = name => `data-${uhyphen(name)}`; const prop = name => name.slice(5).replace(/-([a-z])/g, (_, $1) => $1.toUpperCase()); const handler = { get(dataset, name) { if (name in dataset) return refs.get(dataset).getAttribute(key(name)); }, set(dataset, name, value) { dataset[name] = value; refs.get(dataset).setAttribute(key(name), value); return true; }, deleteProperty(dataset, name) { if (name in dataset) refs.get(dataset).removeAttribute(key(name)); return delete dataset[name]; } }; /** * @implements globalThis.DOMStringMap */ export class DOMStringMap { /** * @param {Element} ref */ constructor(ref) { for (const {name, value} of ref.attributes) { if (/^data-/.test(name)) this[prop(name)] = value; } refs.set(this, ref); return new Proxy(this, handler); } } setPrototypeOf(DOMStringMap.prototype, null);