Commit a547729a authored by Jens Oliver Meiert's avatar Jens Oliver Meiert Committed by David Sveningsson
Browse files

perf: optimize performance with caching and loop refinements

parent d9f22aaa

src/context/context.ts

+13 −8
Original line number Diff line number Diff line
@@ -37,15 +37,20 @@ export class Context { 
	}



	public consume(n: number, state: State): void {

		/* poor mans line counter :( */

		let consumed = this.string.slice(0, n);

		let offset;

		while ((offset = consumed.indexOf("\n")) >= 0) {

			this.line++;

			this.column = 1;

			consumed = consumed.slice(offset + 1);

		let lastNewline = -1;

		let newlines = 0;

		for (let i = 0; i < n; i++) {

			if (this.string[i] === "\n") {

				newlines++;

				lastNewline = i;

			}

		}

		if (newlines > 0) {

			this.line += newlines;

			this.column = n - lastNewline;

		} else {

			this.column += n;

		}

		this.column += consumed.length;

		this.offset += n;



		/* remove N chars */

src/dom/htmlelement.ts

+13 −4
Original line number Diff line number Diff line
@@ -640,10 +640,19 @@ export class HtmlElement extends DOMNode { 
	}



	public getElementsByTagName(tagName: string): HtmlElement[] {

		return this.childElements.reduce<HtmlElement[]>((matches, node) => {

		const matches: HtmlElement[] = [];

		/* eslint-disable-next-line unicorn/prefer-query-selector -- querySelectorAll() is less optimized here */

			return matches.concat(node.is(tagName) ? [node] : [], node.getElementsByTagName(tagName));

		}, []);

		this.collectByTagName(tagName, matches);

		return matches;

	}



	private collectByTagName(tagName: string, matches: HtmlElement[]): void {

		for (const node of this.childElements) {

			if (node.is(tagName)) {

				matches.push(node);

			}

			node.collectByTagName(tagName, matches);

		}

	}



	public querySelector(selector: string): HtmlElement | null {

src/dom/selector/parse-selector.ts

+9 −1
Original line number Diff line number Diff line
@@ -2,12 +2,20 @@ import { ComplexSelector } from "./complex-selector"; 
import { getCompounds } from "./get-compounds";

import { type Selector } from "./selector";



const cache = new Map<string, Selector>();



/**

 * Parse given selector.

 *

 * @internal

 */

export function parseSelector(selector: string): Selector {

	const cached = cache.get(selector);

	if (cached) {

		return cached;

	}

	const compounds = getCompounds(selector);

	return ComplexSelector.fromCompounds(compounds);

	const result = ComplexSelector.fromCompounds(compounds);

	cache.set(selector, result);

	return result;

}