From 29118743a58cf3172bddb6a4fa287484c62b4eb1 Mon Sep 17 00:00:00 2001 From: silverwind Date: Fri, 22 Mar 2024 13:28:38 +0100 Subject: [PATCH] Small refactors in anchors.js (#29947) Some minor refactors, remove unnecessary `:is` selector and move the `:target` check out of the function. Might as well backport for the rare browser that does not support `:is`. --- web_src/js/markup/anchors.js | 40 +++++++++++++++++++----------------- 1 file changed, 21 insertions(+), 19 deletions(-) diff --git a/web_src/js/markup/anchors.js b/web_src/js/markup/anchors.js index dac877fd9..0e2c92713 100644 --- a/web_src/js/markup/anchors.js +++ b/web_src/js/markup/anchors.js @@ -1,29 +1,30 @@ import {svg} from '../svg.js'; +const addPrefix = (str) => `user-content-${str}`; +const removePrefix = (str) => str.replace(/^user-content-/, ''); +const hasPrefix = (str) => str.startsWith('user-content-'); + // scroll to anchor while respecting the `user-content` prefix that exists on the target -function scrollToAnchor(encodedId, initial) { - // abort if the browser has already scrolled to another anchor during page load - if (!encodedId || (initial && document.querySelector(':target'))) return; +function scrollToAnchor(encodedId) { + if (!encodedId) return; const id = decodeURIComponent(encodedId); - let el = document.getElementById(`user-content-${id}`); + const prefixedId = addPrefix(id); + let el = document.getElementById(prefixedId); // check for matching user-generated `a[name]` if (!el) { - const nameAnchors = document.getElementsByName(`user-content-${id}`); + const nameAnchors = document.getElementsByName(prefixedId); if (nameAnchors.length) { el = nameAnchors[0]; } } // compat for links with old 'user-content-' prefixed hashes - if (!el && id.startsWith('user-content-')) { - const el = document.getElementById(id); - if (el) el.scrollIntoView(); + if (!el && hasPrefix(id)) { + return document.getElementById(id)?.scrollIntoView(); } - if (el) { - el.scrollIntoView(); - } + el?.scrollIntoView(); } export function initMarkupAnchors() { @@ -32,11 +33,10 @@ export function initMarkupAnchors() { for (const markupEl of markupEls) { // create link icons for markup headings, the resulting link href will remove `user-content-` - for (const heading of markupEl.querySelectorAll(`:is(h1, h2, h3, h4, h5, h6`)) { - const originalId = heading.id.replace(/^user-content-/, ''); + for (const heading of markupEl.querySelectorAll('h1, h2, h3, h4, h5, h6')) { const a = document.createElement('a'); a.classList.add('anchor'); - a.setAttribute('href', `#${encodeURIComponent(originalId)}`); + a.setAttribute('href', `#${encodeURIComponent(removePrefix(heading.id))}`); a.innerHTML = svg('octicon-link'); heading.prepend(a); } @@ -45,8 +45,7 @@ export function initMarkupAnchors() { for (const a of markupEl.querySelectorAll('a[href^="#"]')) { const href = a.getAttribute('href'); if (!href.startsWith('#user-content-')) continue; - const originalId = href.replace(/^#user-content-/, ''); - a.setAttribute('href', `#${originalId}`); + a.setAttribute('href', `#${removePrefix(href.substring(1))}`); } // add `user-content-` prefix to user-generated `a[name]` link targets @@ -54,15 +53,18 @@ export function initMarkupAnchors() { for (const a of markupEl.querySelectorAll('a[name]')) { const name = a.getAttribute('name'); if (!name) continue; - a.setAttribute('name', `user-content-${a.name}`); + a.setAttribute('name', addPrefix(a.name)); } for (const a of markupEl.querySelectorAll('a[href^="#"]')) { a.addEventListener('click', (e) => { - scrollToAnchor(e.currentTarget.getAttribute('href')?.substring(1), false); + scrollToAnchor(e.currentTarget.getAttribute('href')?.substring(1)); }); } } - scrollToAnchor(window.location.hash.substring(1), true); + // scroll to anchor unless the browser has already scrolled somewhere during page load + if (!document.querySelector(':target')) { + scrollToAnchor(window.location.hash?.substring(1)); + } }