From 2ad76a4bf1318c1f7741de5a4b86df21201a6f62 Mon Sep 17 00:00:00 2001
From: sebastien <lorber.sebastien@gmail.com>
Date: Mon, 2 Nov 2026 10:42:15 +0100
Subject: [PATCH] refactor: use Node.js 26 built-ins for locale calendars and
 the MDX processors cache (AI-assisted)

- Intl.Locale: V8 14.6 removed the non-standard `calendars` getter, use `getCalendars()`
- MDX processors cache: use `Map.prototype.getOrInsertComputed()`

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---
 packages/docusaurus-mdx-loader/src/processor.ts | 10 +++-------
 packages/docusaurus/src/server/i18n.ts          | 15 ++-------------
 2 files changed, 5 insertions(+), 20 deletions(-)

diff --git a/packages/docusaurus-mdx-loader/src/processor.ts b/packages/docusaurus-mdx-loader/src/processor.ts
index ac311aa2c061..ded4525cb12b 100644
--- a/packages/docusaurus-mdx-loader/src/processor.ts
+++ b/packages/docusaurus-mdx-loader/src/processor.ts
@@ -278,13 +278,9 @@ function createProcessorsCacheEntry({
 }: {
   options: Options;
 }): SimpleProcessors {
-  const compilers = ProcessorsCache.get(options);
-  if (compilers) {
-    return compilers;
-  }
-  const processors = createProcessors({options});
-  ProcessorsCache.set(options, processors);
-  return processors;
+  return ProcessorsCache.getOrInsertComputed(options, () =>
+    createProcessors({options}),
+  );
 }
 
 export function getProcessor({
diff --git a/packages/docusaurus/src/server/i18n.ts b/packages/docusaurus/src/server/i18n.ts
index e565453d4b3d..251495cd6bcb 100644
--- a/packages/docusaurus/src/server/i18n.ts
+++ b/packages/docusaurus/src/server/i18n.ts
@@ -60,19 +60,8 @@ function getDefaultCalendar(localeStr: string) {
     return locale.calendar;
   }
 
-  // Not well-supported but server code can infer a calendar from the locale
-  // See https://developer.mozilla.org/fr/docs/Web/JavaScript/Reference/Global_Objects/Intl/Locale/getCalendars
-  // See https://caniuse.com/mdn-javascript_builtins_intl_locale_getcalendars
-  const calendars =
-    locale.getCalendars?.() ??
-    // @ts-expect-error: non-std attribute (V8/Chromium/Node)
-    locale.calendars;
-
-  if (calendars instanceof Array && calendars[0]) {
-    return calendars[0];
-  }
-
-  return 'gregory';
+  // Calendars are sorted by preference
+  return locale.getCalendars()[0] ?? 'gregory';
 }
 
 function getDefaultDirection(localeStr: string) {