@asamuzakjp/dom-selector

DOM Selector

A CSS selector engine.

Install

npm i @asamuzakjp/dom-selector

Usage

import { DOMSelector } from '@asamuzakjp/dom-selector';
import { JSDOM } from 'jsdom';

const { window } = new JSDOM();
const {
  closest, matches, querySelector, querySelectorAll
} = new DOMSelector(window);

matches(selector, node, opt)

matches - equivalent to Element.matches()

Parameters

• selector string CSS selector
• node object Element node
• opt object? options
  • opt.noexcept boolean? no exception
  • opt.warn boolean? console warn e.g. unsupported pseudo-class

Returns boolean true if matched, false otherwise

closest(selector, node, opt)

closest - equivalent to Element.closest()

Parameters

• selector string CSS selector
• node object Element node
• opt object? options
  • opt.noexcept boolean? no exception
  • opt.warn boolean? console warn e.g. unsupported pseudo-class

Returns object? matched node

querySelector(selector, node, opt)

querySelector - equivalent to Document.querySelector(), DocumentFragment.querySelector() and Element.querySelector()

Parameters

• selector string CSS selector
• node object Document, DocumentFragment or Element node
• opt object? options
  • opt.noexcept boolean? no exception
  • opt.warn boolean? console warn e.g. unsupported pseudo-class

Returns object? matched node

querySelectorAll(selector, node, opt)

querySelectorAll - equivalent to Document.querySelectorAll(), DocumentFragment.querySelectorAll() and Element.querySelectorAll()
NOTE: returns Array, not NodeList

Parameters

• selector string CSS selector
• node object Document, DocumentFragment or Element node
• opt object? options
  • opt.noexcept boolean? no exception
  • opt.warn boolean? console warn e.g. unsupported pseudo-class

Returns Array<(object | undefined)> array of matched nodes

Monkey patch jsdom

import { DOMSelector } from '@asamuzakjp/dom-selector';
import { JSDOM } from 'jsdom';

const dom = new JSDOM('', {
  runScripts: 'dangerously',
  url: 'http://localhost/',
  beforeParse: window => {
    const domSelector = new DOMSelector(window);

    const matches = domSelector.matches.bind(domSelector);
    window.Element.prototype.matches = function (...args) {
      if (!args.length) {
        throw new window.TypeError('1 argument required, but only 0 present.');
      }
      const [selector] = args;
      return matches(selector, this);
    };

    const closest = domSelector.closest.bind(domSelector);
    window.Element.prototype.closest = function (...args) {
      if (!args.length) {
        throw new window.TypeError('1 argument required, but only 0 present.');
      }
      const [selector] = args;
      return closest(selector, this);
    };

    const querySelector = domSelector.querySelector.bind(domSelector);
    window.Document.prototype.querySelector = function (...args) {
      if (!args.length) {
        throw new window.TypeError('1 argument required, but only 0 present.');
      }
      const [selector] = args;
      return querySelector(selector, this);
    };
    window.DocumentFragment.prototype.querySelector = function (...args) {
      if (!args.length) {
        throw new window.TypeError('1 argument required, but only 0 present.');
      }
      const [selector] = args;
      return querySelector(selector, this);
    };
    window.Element.prototype.querySelector = function (...args) {
      if (!args.length) {
        throw new window.TypeError('1 argument required, but only 0 present.');
      }
      const [selector] = args;
      return querySelector(selector, this);
    };

    const querySelectorAll = domSelector.querySelectorAll.bind(domSelector);
    window.Document.prototype.querySelectorAll = function (...args) {
      if (!args.length) {
        throw new window.TypeError('1 argument required, but only 0 present.');
      }
      const [selector] = args;
      return querySelectorAll(selector, this);
    };
    window.DocumentFragment.prototype.querySelectorAll = function (...args) {
      if (!args.length) {
        throw new window.TypeError('1 argument required, but only 0 present.');
      }
      const [selector] = args;
      return querySelectorAll(selector, this);
    };
    window.Element.prototype.querySelectorAll = function (...args) {
      if (!args.length) {
        throw new window.TypeError('1 argument required, but only 0 present.');
      }
      const [selector] = args;
      return querySelectorAll(selector, this);
    };
  }
});

Supported CSS selectors

Pattern	Supported	Note
*	✓
ns|E	✓
*|E	✓
|E	✓
E	✓
E:not(s1, s2, …)	✓
E:is(s1, s2, …)	✓
E:where(s1, s2, …)	✓
E:has(rs1, rs2, …)	✓
E.warning	✓
E#myid	✓
E[foo]	✓
E[foo="bar"]	✓
E[foo="bar" i]	✓
E[foo="bar" s]	✓
E[foo~="bar"]	✓
E[foo^="bar"]	✓
E[foo$="bar"]	✓
E[foo*="bar"]	✓
E[foo|="en"]	✓
E:defined	Partially supported	Matching with MathML is not yet supported.
E:dir(ltr)	✓
E:lang(en)	✓
E:any‑link	✓
E:link	✓
E:visited	✓	Returns false or null to prevent fingerprinting.
E:local‑link	✓
E:target	✓
E:target‑within	✓
E:scope	✓
E:current	Unsupported
E:current(s)	Unsupported
E:past	Unsupported
E:future	Unsupported
E:active	✓
E:hover	✓
E:focus	✓
E:focus‑within	✓
E:focus‑visible	✓
E:open E:closed	Partially supported	Matching with <select>, e.g. select:open, is not supported.
E:enabled E:disabled	✓
E:read‑write E:read‑only	✓
E:placeholder‑shown	✓
E:default	✓
E:checked	✓
E:indeterminate	✓
E:valid E:invalid	✓
E:required E:optional	✓
E:blank	Unsupported
E:user‑valid E:user‑invalid	Unsupported
E:root	✓
E:empty	✓
E:nth‑child(n [of S]?)	✓
E:nth‑last‑child(n [of S]?)	✓
E:first‑child	✓
E:last‑child	✓
E:only‑child	✓
E:nth‑of‑type(n)	✓
E:nth‑last‑of‑type(n)	✓
E:first‑of‑type	✓
E:last‑of‑type	✓
E:only‑of‑type	✓
E F	✓
E > F	✓
E + F	✓
E ~ F	✓
F || E	Unsupported
E:nth‑col(n)	Unsupported
E:nth‑last‑col(n)	Unsupported
E:popover-open	✓
E:state(v)	✓	*1
:host	✓
:host(s)	✓
:host‑context(s)	✓
:host(:state(v))	✓	*1
:host:has(rs1, rs2, ...)	✓
:host(s):has(rs1, rs2, ...)	✓
:host‑context(s):has(rs1, rs2, ...)	✓

*1: ElementInternals.states, i.e. CustomStateSet, is not implemented in jsdom, so you need to apply a patch in the custom element constructor.

class LabeledCheckbox extends window.HTMLElement {
  #internals;
  constructor() {
    super();
    this.#internals = this.attachInternals();
    // patch CustomStateSet
    if (!this.#internals.states) {
      this.#internals.states = new Set();
    }
    this.addEventListener('click', this._onClick.bind(this));
  }
  get checked() {
    return this.#internals.states.has('checked');
  }
  set checked(flag) {
    if (flag) {
      this.#internals.states.add('checked');
    } else {
      this.#internals.states.delete('checked');
    }
  }
  _onClick(event) {
    this.checked = !this.checked;
  }
}

Performance

See benchmark for the latest results.

F: Failed because the selector is not supported or the result was incorrect.

matches()

Selector	jsdom v25.0.1 (nwsapi)	happy-dom	linkeDom	patched-jsdom (dom-selector)	Result
simple selector: matches('.content')	115,054 ops/sec ±2.48%	356,979 ops/sec ±2.34%	8,556 ops/sec ±0.90%	118,715 ops/sec ±0.17%	happydom is the fastest and 3.0 times faster than patched-jsdom. patched-jsdom is 1.0 times faster than jsdom.
compound selector: matches('p.content[id]:is(:last-child, :only-child)')	109,730 ops/sec ±0.63%	323,008 ops/sec ±18.02%	8,419 ops/sec ±0.66%	86,074 ops/sec ±0.97%	happydom is the fastest and 3.8 times faster than patched-jsdom. jsdom is 1.3 times faster than patched-jsdom.
compound selector: matches('p.content[id]:is(:invalid-nth-child, :only-child)')	F	353,239 ops/sec ±2.73%	F	43,662 ops/sec ±1.86%	happydom is the fastest and 8.1 times faster than patched-jsdom.
compound selector: matches('p.content[id]:not(:is(.foo, .bar))')	101,636 ops/sec ±1.59%	351,747 ops/sec ±0.59%	8,082 ops/sec ±0.61%	83,928 ops/sec ±0.66%	happydom is the fastest and 4.2 times faster than patched-jsdom. jsdom is 1.2 times faster than patched-jsdom.
complex selector: matches('.box:first-child ~ .box:nth-of-type(4n+1) + .box[id] .block.inner > .content')	70,482 ops/sec ±0.38%	F	5,261 ops/sec ±0.72%	61,745 ops/sec ±0.56%	jsdom is the fastest and 1.1 times faster than patched-jsdom.
complex selector: matches('.box:first-child ~ .box:nth-of-type(4n+1) + .box[id] .block.inner:has(> .content)')	31,671 ops/sec ±1.14%	F	5,288 ops/sec ±0.43%	42,614 ops/sec ±2.51%	patched-jsdom is the fastest. patched-jsdom is 1.3 times faster than jsdom.
complex selector within logical pseudo-class: matches(':is(.box > .content, .block > .content)')	100,293 ops/sec ±0.67%	F	5,593 ops/sec ±0.40%	78,292 ops/sec ±26.38%	jsdom is the fastest and 1.3 times faster than patched-jsdom.
nested and chained :not() selector: matches('p:not(:is(:not(.content))):not(.foo)')	F	299,143 ops/sec ±28.61%	5,538 ops/sec ±0.44%	84,061 ops/sec ±0.71%	happydom is the fastest and 3.6 times faster than patched-jsdom.

closest()

Selector	jsdom v25.0.1 (nwsapi)	happy-dom	linkeDom	patched-jsdom (dom-selector)	Result
simple selector: closest('.container')	96,990 ops/sec ±0.60%	326,924 ops/sec ±0.52%	8,453 ops/sec ±0.65%	90,555 ops/sec ±1.70%	happydom is the fastest and 3.6 times faster than patched-jsdom. jsdom is 1.1 times faster than patched-jsdom.
compound selector: closest('div.container[id]:not(.foo, .box)')	63,821 ops/sec ±0.74%	F	7,942 ops/sec ±0.47%	54,674 ops/sec ±0.83%	jsdom is the fastest and 1.2 times faster than patched-jsdom.
complex selector: closest('.box:first-child ~ .box:nth-of-type(4n+1) + .box[id] .block.inner > .content')	65,863 ops/sec ±0.65%	F	5,336 ops/sec ±0.55%	57,088 ops/sec ±0.76%	jsdom is the fastest and 1.2 times faster than patched-jsdom.
complex selector: closest('.box:first-child ~ .box:nth-of-type(4n+1) + .box[id] .block.inner:has(> .content)')	23,941 ops/sec ±1.24%	F	5,182 ops/sec ±1.02%	36,066 ops/sec ±0.48%	patched-jsdom is the fastest. patched-jsdom is 1.5 times faster than jsdom.
complex selector within logical pseudo-class: closest(':is(.container > .content, .container > .box)')	76,340 ops/sec ±0.36%	235,292 ops/sec ±34.48%	5,533 ops/sec ±0.53%	68,793 ops/sec ±0.78%	happydom is the fastest and 3.4 times faster than patched-jsdom. jsdom is 1.1 times faster than patched-jsdom.
nested and chained :not() selector: closest('div:not(:is(:not(.container))):not(.box)')	F	F	7,777 ops/sec ±0.65%	71,028 ops/sec ±0.55%	patched-jsdom is the fastest.

querySelector()

Selector	jsdom v25.0.1 (nwsapi)	happy-dom	linkeDom	patched-jsdom (dom-selector)	Result
simple selector: querySelector('.content')	21,898 ops/sec ±1.84%	265,006 ops/sec ±42.03%	9,921 ops/sec ±0.56%	81,017 ops/sec ±1.27%	happydom is the fastest and 3.3 times faster than patched-jsdom. patched-jsdom is 3.7 times faster than jsdom.
compound selector: querySelector('p.content[id]:is(:last-child, :only-child)')	8,676 ops/sec ±0.71%	327,427 ops/sec ±1.06%	9,507 ops/sec ±0.76%	37,303 ops/sec ±0.95%	happydom is the fastest and 8.8 times faster than patched-jsdom. patched-jsdom is 4.3 times faster than jsdom.
complex selector: querySelector('.box:first-child ~ .box:nth-of-type(4n+1) + .box[id] .block.inner > .content')	197 ops/sec ±0.84%	F	1,230 ops/sec ±0.91%	616 ops/sec ±1.22%	linkedom is the fastest and 2.0 times faster than patched-jsdom. patched-jsdom is 3.1 times faster than jsdom.
complex selector: querySelector('.box:first-child ~ .box:nth-of-type(4n+1) + .box[id] .block.inner:has(> .content)')	57.15 ops/sec ±2.55%	F	1,452 ops/sec ±0.62%	453 ops/sec ±0.95%	linkedom is the fastest and 3.2 times faster than patched-jsdom. patched-jsdom is 7.9 times faster than jsdom.
complex selector within logical pseudo-class: querySelector(':is(.box > .content, .block > .content)')	3,045 ops/sec ±1.16%	F	9,229 ops/sec ±0.76%	74,154 ops/sec ±0.83%	patched-jsdom is the fastest. patched-jsdom is 24.4 times faster than jsdom.
nested and chained :not() selector: querySelector('p:not(:is(:not(.content))):not(.foo)')	F	323,503 ops/sec ±0.95%	9,383 ops/sec ±0.63%	68,866 ops/sec ±0.70%	happydom is the fastest and 4.7 times faster than patched-jsdom.

querySelectorAll()

Selector	jsdom v25.0.1 (nwsapi)	happy-dom	linkeDom	patched-jsdom (dom-selector)	Result
simple selector: querySelectorAll('.content')	973 ops/sec ±49.13%	477 ops/sec ±43.91%	1,134 ops/sec ±0.38%	1,221 ops/sec ±0.69%	patched-jsdom is the fastest. patched-jsdom is 1.3 times faster than jsdom.
compound selector: querySelectorAll('p.content[id]:is(:last-child, :only-child)')	681 ops/sec ±0.58%	572 ops/sec ±3.54%	1,124 ops/sec ±0.80%	640 ops/sec ±0.62%	linkedom is the fastest and 1.8 times faster than patched-jsdom. jsdom is 1.1 times faster than patched-jsdom.
complex selector: querySelectorAll('.box:first-child ~ .box:nth-of-type(4n+1) + .box[id] .block.inner > .content')	198 ops/sec ±0.92%	F	386 ops/sec ±0.74%	206 ops/sec ±0.70%	linkedom is the fastest and 1.9 times faster than patched-jsdom. patched-jsdom is 1.0 times faster than jsdom.
complex selector: querySelectorAll('.box:first-child ~ .box:nth-of-type(4n+1) + .box[id] .block.inner:has(> .content)')	56.19 ops/sec ±1.54%	F	419 ops/sec ±0.47%	183 ops/sec ±0.57%	linkedom is the fastest and 2.3 times faster than patched-jsdom. patched-jsdom is 3.2 times faster than jsdom.
complex selector within logical pseudo-class: querySelectorAll(':is(.box > .content, .block > .content)')	276 ops/sec ±0.97%	F	468 ops/sec ±0.74%	811 ops/sec ±1.18%	patched-jsdom is the fastest. patched-jsdom is 2.9 times faster than jsdom.
nested and chained :not() selector: querySelectorAll('p:not(:is(:not(.content))):not(.foo)')	F	523 ops/sec ±5.90%	1,160 ops/sec ±1.16%	1,321 ops/sec ±0.52%	patched-jsdom is the fastest.

Acknowledgments

The following resources have been of great help in the development of the DOM Selector.

• CSSTree
• selery
• jsdom
• nwsapi

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Copyright (c) 2023 asamuzaK (Kazz)