@@ -1,18 +1,28 @@
-// Linkinator treats the following as regex.
+/**
+ * This file exports a mix of strings and of regexes. Linkinator relies
+ * on this in `script/check-english-links.js` when we encounter external
+ * links that we *specifically ignore*. That means, that URLs or patterns
+ * mentioned in this file might appear within our content but we don't
+ * bother checking that they actually work.
+ */
+
+/* eslint-disable prefer-regex-literals */
+
 export default [
   // Skip GitHub search links.
-  'https://github.com/search\\?',
-  'https://github.com/github/gitignore/search\\?',
+  // E.g. https://github.com/search?foo=bar
+  new RegExp('https://github\\.com/search\\?'),
+  new RegExp('https://github\\.com/github/gitignore/search\\?'),
 
   // These links require auth.
-  'https://github.com/settings/profile',
-  'https://github.com/github/docs/edit',
-  'https://github.com/github/insights-releases/releases/latest',
-  'https://classroom.github.com/videos',
+  new RegExp('https://github\\.com/settings/profile'),
+  new RegExp('https://github\\.com/github/docs/edit'),
+  new RegExp('https://github\\.com/github/insights-releases/releases/latest'),
+  new RegExp('https://classroom\\.github.com/videos'),
 
   // Oneoff links that link checkers think are broken but are not.
   'https://haveibeenpwned.com/',
-  'https://www.ilo.org/dyn/normlex/en/f\\?p=NORMLEXPUB:12100:0::NO::P12100_ILO_CODE:P029',
+  'https://www.ilo.org/dyn/normlex/en/f?p=NORMLEXPUB:12100:0::NO::P12100_ILO_CODE:P029',
   'https://www.linkedin.com/company/github',
   'https://www.facebook.com/',
   'https://ko-fi.com/',
 
@@ -52,7 +52,7 @@ program
 // Skip non-English content.
 const languagesToSkip = Object.keys(libLanguages)
   .filter((code) => code !== 'en')
-  .map((code) => `${root}/${code}`)
+  .map((code) => new RegExp(`${root}/${code}`))
 
 // Skip deprecated Enterprise content.
 // Capture the old format https://docs.github.com/enterprise/2.1/
@@ -66,7 +66,19 @@ const config = {
   recurse: !program.opts().dryRun,
   silent: true,
   // The values in this array are treated as regexes.
-  linksToSkip: [enterpriseReleasesToSkip, ...languagesToSkip, ...excludedLinks],
+  linksToSkip: linksToSkipFactory([enterpriseReleasesToSkip, ...languagesToSkip, ...excludedLinks]),
+}
+
+// Return a function that can as quickly as possible check if a certain
+// href input should be skipped.
+// Do this so we can use a `Set` and a `iterable.some()` for a speedier
+// check. The default implementation in Linkinator, if you set
+// the `linksToSkip` config to be an array, it will, for every URL it
+// checks turn that into a new regex every single time.
+function linksToSkipFactory(regexAndURLs) {
+  const set = new Set(regexAndURLs.filter((regexOrURL) => typeof regexOrURL === 'string'))
+  const regexes = regexAndURLs.filter((regexOrURL) => regexOrURL instanceof RegExp)
+  return (href) => set.has(href) || regexes.some((regex) => regex.test(href))
 }
 
 main()
 
@@ -79,6 +79,7 @@ const IGNORE_PATHS = [
   '.vscode', // Not part of the repo but could be for a developer locally
   'node_modules',
   'translations',
+  '.linkinator',
   '**/*.png', // Do not check images or font files.
   '**/*.jpg', // We could just put all of assets/* here, but that would prevent any
   '**/*.gif', // READMEs or other text-based files from being checked.