diff --git a/src/content/navigates.js b/src/content/navigates.js index 3e12a6f..c9baa30 100644 --- a/src/content/navigates.js +++ b/src/content/navigates.js @@ -1,18 +1,18 @@ -const PREV_LINK_PATTERNS = [ - /\bprev\b/i, /\bprevious\b/i, /\bback\b/i, - //, /\u203a/, /\u2192/, /\xbb/, /\u226b/, />>/ -]; - -const findLinkByPatterns = (win, patterns) => { - const links = win.document.getElementsByTagName('a'); - return Array.prototype.find.call(links, (link) => { - return patterns.some(ptn => ptn.test(link.textContent)); - }); +const REL_PATTERN = { + prev: /^(?:prev(?:ious)?|older)\b|\u2039|\u2190|\xab|\u226a|<>/i, +}; + +// Return the last element in the document matching the supplied selector +// and the optional filter, or null if there are no matches. +const selectLast = (win, selector, filter) => { + let nodes = win.document.querySelectorAll(selector); + + if (filter) { + nodes = Array.from(nodes).filter(filter); + } + + return nodes.length ? nodes[nodes.length - 1] : null; }; const historyPrev = (win) => { @@ -23,16 +23,21 @@ const historyNext = (win) => { win.history.forward(); }; -const linkCommon = (win, rel, patterns) => { - let link = win.document.querySelector(`link[rel~=${rel}][href]`); +// Code common to linkPrev and linkNext which navigates to the specified page. +const linkRel = (win, rel) => { + let link = selectLast(win, `link[rel~=${rel}][href]`); if (link) { - win.location = link.getAttribute('href'); + win.location = link.href; return; } - link = win.document.querySelector(`a[rel~=${rel}]`) || - findLinkByPatterns(win, patterns); + const pattern = REL_PATTERN[rel]; + + link = selectLast(win, `a[rel~=${rel}][href]`) || + // `innerText` is much slower than `textContent`, but produces much better + // (i.e. less unexpected) results + selectLast(win, 'a[href]', lnk => pattern.test(lnk.innerText)); if (link) { link.click(); @@ -40,11 +45,11 @@ const linkCommon = (win, rel, patterns) => { }; const linkPrev = (win) => { - linkCommon(win, 'prev', PREV_LINK_PATTERNS); + linkRel(win, 'prev'); }; const linkNext = (win) => { - linkCommon(win, 'next', NEXT_LINK_PATTERNS); + linkRel(win, 'next'); }; const parent = (win) => { diff --git a/test/content/navigates.test.js b/test/content/navigates.test.js index d8a3316..f1f0741 100644 --- a/test/content/navigates.test.js +++ b/test/content/navigates.test.js @@ -53,7 +53,7 @@ describe('navigates module', () => { )); it('navigates to elements whose text matches "previous"', testPrev( - 'previewgo to previous' + 'previouslyprevious page' )); it('navigates to elements whose decoded text matches "<<"', testPrev( @@ -119,11 +119,11 @@ describe('navigates module', () => { )); it('prefers link[rel~=next] to a[rel~=next]', testNext( - '' )); it('prefers a[rel~=next] to a::text(pattern)', testNext( - 'go to next' + 'next page' )); });