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:openE:closed|Partially supported|Matching with <select>, e.g. select:open, is not supported.| |E:enabledE:disabled|✓| | |E:read‑writeE:read‑only|✓| | |E:placeholder‑shown|✓| | |E:default|✓| | |E:checked|✓| | |E:indeterminate|✓| | |E:validE:invalid|✓| | |E:requiredE:optional|✓| | |E:blank|Unsupported| | |E:user‑validE: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')|117,468 ops/sec ±4.45%|349,037 ops/sec ±2.71%|7,986 ops/sec ±0.83%|121,277 ops/sec ±0.58%|happydom is the fastest and 2.9 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)')|109,103 ops/sec ±1.81%|323,742 ops/sec ±16.05%|7,826 ops/sec ±0.70%|89,905 ops/sec ±0.25%|happydom is the fastest and 3.6 times faster than patched-jsdom. jsdom is 1.2 times faster than patched-jsdom.| |compound selector:matches('p.content[id]:is(:invalid-nth-child, :only-child)')|F|350,215 ops/sec ±2.68%|F|44,510 ops/sec ±0.33%|happydom is the fastest and 7.9 times faster than patched-jsdom.| |compound selector:matches('p.content[id]:not(:is(.foo, .bar))')|106,858 ops/sec ±0.43%|352,297 ops/sec ±0.17%|7,639 ops/sec ±0.61%|87,013 ops/sec ±0.63%|happydom is the fastest and 4.0 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')|70,868 ops/sec ±0.57%|F|4,876 ops/sec ±0.49%|64,719 ops/sec ±0.36%|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)')|F|F|4,752 ops/sec ±0.54%|15,398 ops/sec ±3.41%|patched-jsdom is the fastest.| |complex selector within logical pseudo-class:matches(':is(.box > .content, .block > .content)')|99,626 ops/sec ±0.63%|F|5,129 ops/sec ±0.45%|95,577 ops/sec ±0.65%|jsdom is the fastest and 1.0 times faster than patched-jsdom.| |nested and chained :not() selector:matches('p:not(:is(:not(.content))):not(.foo)')|F|F|4,701 ops/sec ±13.49%|82,153 ops/sec ±0.68%|patched-jsdom is the fastest.|

closest()

|Selector|jsdom v25.0.1 (nwsapi)|happy-dom|linkeDom|patched-jsdom (dom-selector)|Result| |:-----------|:-----------|:-----------|:-----------|:-----------|:-----------| |simple selector:closest('.container')|93,212 ops/sec ±0.46%|263,009 ops/sec ±30.00%|7,996 ops/sec ±0.64%|91,205 ops/sec ±0.35%|happydom is the fastest and 2.9 times faster than patched-jsdom. jsdom is 1.0 times faster than patched-jsdom.| |compound selector:closest('div.container[id]:not(.foo, .box)')|64,257 ops/sec ±0.27%|F|7,412 ops/sec ±0.84%|55,072 ops/sec ±0.33%|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')|65,291 ops/sec ±0.22%|F|4,890 ops/sec ±0.41%|58,028 ops/sec ±0.64%|jsdom is the fastest and 1.1 times faster than patched-jsdom.| |complex selector:closest('.box:first-child ~ .box:nth-of-type(4n+1) + .box[id] .block.inner:has(> .content)')|F|F|4,703 ops/sec ±1.06%|13,256 ops/sec ±0.48%|patched-jsdom is the fastest.| |complex selector within logical pseudo-class:closest(':is(.container > .content, .container > .box)')|75,927 ops/sec ±0.36%|307,805 ops/sec ±0.48%|5,108 ops/sec ±0.41%|69,864 ops/sec ±0.18%|happydom is the fastest and 4.4 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|7,399 ops/sec ±0.61%|70,308 ops/sec ±0.48%|patched-jsdom is the fastest.|

querySelector()

|Selector|jsdom v25.0.1 (nwsapi)|happy-dom|linkeDom|patched-jsdom (dom-selector)|Result| |:-----------|:-----------|:-----------|:-----------|:-----------|:-----------| |simple selector:querySelector('.content')|22,886 ops/sec ±0.82%|193,155 ops/sec ±54.70%|9,439 ops/sec ±0.63%|78,132 ops/sec ±0.17%|happydom is the fastest and 2.5 times faster than patched-jsdom. patched-jsdom is 3.4 times faster than jsdom.| |compound selector:querySelector('p.content[id]:is(:last-child, :only-child)')|8,542 ops/sec ±0.62%|336,066 ops/sec ±0.67%|9,046 ops/sec ±0.77%|35,397 ops/sec ±1.69%|happydom is the fastest and 9.5 times faster than patched-jsdom. patched-jsdom is 4.1 times faster than jsdom.| |complex selector:querySelector('.box:first-child ~ .box:nth-of-type(4n+1) + .box[id] .block.inner > .content')|204 ops/sec ±0.44%|F|1,186 ops/sec ±0.50%|626 ops/sec ±0.57%|linkedom is the fastest and 1.9 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)')|F|F|1,476 ops/sec ±0.74%|453 ops/sec ±0.78%|linkedom is the fastest and 3.3 times faster than patched-jsdom.| |complex selector within logical pseudo-class:querySelector(':is(.box > .content, .block > .content)')|3,144 ops/sec ±0.45%|F|8,766 ops/sec ±0.78%|77,257 ops/sec ±0.50%|patched-jsdom is the fastest. patched-jsdom is 24.6 times faster than jsdom.| |nested and chained :not() selector:querySelector('p:not(:is(:not(.content))):not(.foo)')|F|F|8,972 ops/sec ±0.70%|70,248 ops/sec ±0.39%|patched-jsdom is the fastest.|

querySelectorAll()

|Selector|jsdom v25.0.1 (nwsapi)|happy-dom|linkeDom|patched-jsdom (dom-selector)|Result| |:-----------|:-----------|:-----------|:-----------|:-----------|:-----------| |simple selector:querySelectorAll('.content')|1,292 ops/sec ±0.58%|494 ops/sec ±44.77%|1,091 ops/sec ±0.72%|1,226 ops/sec ±0.45%|jsdom is the fastest and 1.1 times faster than patched-jsdom.| |compound selector:querySelectorAll('p.content[id]:is(:last-child, :only-child)')|688 ops/sec ±0.91%|455 ops/sec ±42.98%|1,096 ops/sec ±0.90%|656 ops/sec ±0.50%|linkedom is the fastest and 1.7 times faster than patched-jsdom. jsdom is 1.0 times faster than patched-jsdom.| |complex selector:querySelectorAll('.box:first-child ~ .box:nth-of-type(4n+1) + .box[id] .block.inner > .content')|206 ops/sec ±0.58%|F|393 ops/sec ±0.62%|209 ops/sec ±0.58%|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)')|F|F|421 ops/sec ±0.83%|186 ops/sec ±0.49%|linkedom is the fastest and 2.3 times faster than patched-jsdom.| |complex selector within logical pseudo-class:querySelectorAll(':is(.box > .content, .block > .content)')|288 ops/sec ±0.64%|F|471 ops/sec ±0.71%|796 ops/sec ±2.11%|patched-jsdom is the fastest. patched-jsdom is 2.8 times faster than jsdom.| |nested and chained :not() selector:querySelectorAll('p:not(:is(:not(.content))):not(.foo)')|F|F|1,108 ops/sec ±0.45%|1,316 ops/sec ±0.48%|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

Copyright (c) 2023 asamuzaK (Kazz)