feat: allow setting calendar for i18n date formatting (#6430)

* feat: allow setting calendar for i18n date formatting

* fix TS

* add test

packages/docusaurus-plugin-content-blog/src/__tests__/feed.test.ts

@@ -19,7 +19,11 @@ const DefaultI18N: I18n = {
   currentLocale: 'en',
   locales: ['en'],
   defaultLocale: 'en',
-  localeConfigs: {},
+  localeConfigs: {
+    en: {
+      calendar: 'gregory',
+    },
+  },
 };
 
 function getBlogContentPaths(siteDir: string): BlogContentPaths {

packages/docusaurus-plugin-content-blog/src/__tests__/index.test.ts

@@ -41,7 +41,7 @@ function getI18n(locale: string): I18n {
     currentLocale: locale,
     locales: [locale],
     defaultLocale: locale,
-    localeConfigs: {},
+    localeConfigs: {[locale]: {calendar: 'gregory'}},
   };
 }
 

packages/docusaurus-plugin-content-blog/src/blogUtils.ts

@@ -151,13 +151,18 @@ export function parseBlogFileName(
   return {date: undefined, text, slug};
 }
 
-function formatBlogPostDate(locale: string, date: Date): string {
+function formatBlogPostDate(
+  locale: string,
+  date: Date,
+  calendar: string,
+): string {
   try {
     return new Intl.DateTimeFormat(locale, {
       day: 'numeric',
       month: 'long',
       year: 'numeric',
       timeZone: 'UTC',
+      calendar,
     }).format(date);
   } catch (err) {
     logger.error`Can't format blog post date "${String(date)}"`;
@@ -253,7 +258,11 @@ async function processBlogSourceFile(
   }
 
   const date = await getDate();
-  const formattedDate = formatBlogPostDate(i18n.currentLocale, date);
+  const formattedDate = formatBlogPostDate(
+    i18n.currentLocale,
+    date,
+    i18n.localeConfigs[i18n.currentLocale]!.calendar,
+  );
 
   const title = frontMatter.title ?? contentTitle ?? parsedBlogFileName.text;
   const description = frontMatter.description ?? excerpt ?? '';

packages/docusaurus-plugin-content-docs/src/docs.ts

@@ -254,9 +254,9 @@ function doProcessDocMetadata({
     lastUpdatedBy: lastUpdate.lastUpdatedBy,
     lastUpdatedAt: lastUpdate.lastUpdatedAt,
     formattedLastUpdatedAt: lastUpdate.lastUpdatedAt
-      ? new Intl.DateTimeFormat(i18n.currentLocale).format(
-          lastUpdate.lastUpdatedAt * 1000,
-        )
+      ? new Intl.DateTimeFormat(i18n.currentLocale, {
+          calendar: i18n.localeConfigs[i18n.currentLocale]!.calendar,
+        }).format(lastUpdate.lastUpdatedAt * 1000)
       : undefined,
     sidebarPosition,
     frontMatter,

packages/docusaurus-types/src/index.d.ts

@@ -45,6 +45,7 @@ export type I18nLocaleConfig = {
   label: string;
   htmlLang: string;
   direction: string;
+  calendar: string;
 };
 
 export type I18nConfig = {

packages/docusaurus/src/server/__tests__/i18n.test.ts

@@ -32,48 +32,63 @@ describe('defaultLocaleConfig', () => {
       label: 'Français',
       direction: 'ltr',
       htmlLang: 'fr',
+      calendar: 'gregory',
     });
     expect(getDefaultLocaleConfig('fr-FR')).toEqual({
       label: 'Français (France)',
       direction: 'ltr',
       htmlLang: 'fr-FR',
+      calendar: 'gregory',
     });
     expect(getDefaultLocaleConfig('en')).toEqual({
       label: 'English',
       direction: 'ltr',
       htmlLang: 'en',
+      calendar: 'gregory',
     });
     expect(getDefaultLocaleConfig('en-US')).toEqual({
       label: 'American English',
       direction: 'ltr',
       htmlLang: 'en-US',
+      calendar: 'gregory',
     });
     expect(getDefaultLocaleConfig('zh')).toEqual({
       label: '中文',
       direction: 'ltr',
       htmlLang: 'zh',
+      calendar: 'gregory',
     });
     expect(getDefaultLocaleConfig('zh-CN')).toEqual({
       label: '中文（中国）',
       direction: 'ltr',
       htmlLang: 'zh-CN',
+      calendar: 'gregory',
     });
     expect(getDefaultLocaleConfig('en-US')).toEqual({
       label: 'American English',
       direction: 'ltr',
       htmlLang: 'en-US',
+      calendar: 'gregory',
     });
     expect(getDefaultLocaleConfig('fa')).toEqual({
       // cSpell:ignore فارسی
       label: 'فارسی',
       direction: 'rtl',
       htmlLang: 'fa',
+      calendar: 'gregory',
     });
     expect(getDefaultLocaleConfig('fa-IR')).toEqual({
       // cSpell:ignore ایران فارسیا
       label: 'فارسی (ایران)',
       direction: 'rtl',
       htmlLang: 'fa-IR',
+      calendar: 'gregory',
+    });
+    expect(getDefaultLocaleConfig('en-US-u-ca-buddhist')).toEqual({
+      label: 'American English',
+      direction: 'ltr',
+      htmlLang: 'en-US-u-ca-buddhist',
+      calendar: 'buddhist',
     });
   });
 });
@@ -144,7 +159,12 @@ describe('loadI18n', () => {
       locales: ['en', 'fr', 'de'],
       currentLocale: 'de',
       localeConfigs: {
-        fr: {label: 'Français', direction: 'ltr', htmlLang: 'fr'},
+        fr: {
+          label: 'Français',
+          direction: 'ltr',
+          htmlLang: 'fr',
+          calendar: 'gregory',
+        },
         en: getDefaultLocaleConfig('en'),
         de: getDefaultLocaleConfig('de'),
       },

packages/docusaurus/src/server/configValidation.ts

@@ -131,6 +131,7 @@ const LocaleConfigSchema = Joi.object({
   label: Joi.string(),
   htmlLang: Joi.string(),
   direction: Joi.string().equal('ltr', 'rtl').default('ltr'),
+  calendar: Joi.string(),
 });
 
 const I18N_CONFIG_SCHEMA = Joi.object<I18nConfig>({

packages/docusaurus/src/server/i18n.ts

@@ -24,6 +24,8 @@ export function getDefaultLocaleConfig(locale: string): I18nLocaleConfig {
     label: getDefaultLocaleLabel(locale),
     direction: getLangDir(locale),
     htmlLang: locale,
+    // If the locale name includes -u-ca-xxx the calendar will be defined
+    calendar: new Intl.Locale(locale).calendar ?? 'gregory',
   };
 }
 

website/docs/api/docusaurus.config.js.md

@@ -124,6 +124,8 @@ The i18n configuration object to [localize your site](../i18n/i18n-introduction.
 
 Example:
 
+<!-- cSpell:ignore فارسی -->
+
 ```js title="docusaurus.config.js"
 module.exports = {
   i18n: {
@@ -134,11 +136,13 @@ module.exports = {
         label: 'English',
         direction: 'ltr',
         htmlLang: 'en-US',
+        calendar: 'gregory',
       },
-      fr: {
-        label: 'Français',
-        direction: 'ltr',
-        htmlLang: 'fr-FR',
+      fa: {
+        label: 'فارسی',
+        direction: 'rtl',
+        htmlLang: 'fa-IR',
+        calendar: 'persian',
       },
     },
   },
@@ -148,6 +152,7 @@ module.exports = {
 - `label`: the label to use for this locale
 - `direction`: `ltr` (default) or `rtl` (for [right-to-left languages](https://developer.mozilla.org/en-US/docs/Glossary/rtl) like Arabic, Hebrew, etc.)
 - `htmlLang`: BCP 47 language tag to use in `<html lang="...">` and in `<link ... hreflang="...">`
+- `calendar`: the [calendar](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/Locale/calendar) used to calculate the date era. Note that it doesn't control the actual string displayed: `MM/DD/YYYY` and `DD/MM/YYYY` are both `gregory`. To choose the format (`DD/MM/YYYY` or `MM/DD/YYYY`), set your locale name to `en-GB` or `en-US` (`en` means `en-US`).
 
 ### `noIndex` {#noindex}