fix(i18n): return value from preferredLocale (#13524)

* fix(i18n): return value from `preferredLocale`

* revert change

Co-authored-by: florian-lefebvre <[email protected]>

Author: ematipico

.changeset/ninety-nights-hug.md

@@ -0,0 +1,7 @@
+---
+'astro': patch
+---
+
+Fixes a bug where the functions `Astro.preferredLocale` and `Astro.preferredLocaleList` would return the incorrect locales 
+when the Astro configuration specifies a list of `codes`. Before, the functions would return the `path`, instead now the functions 
+return a list built from `codes`.

packages/astro/src/i18n/index.ts

@@ -229,6 +229,18 @@ export function normalizeTheLocale(locale: string): string {
  * Returns an array of only locales, by picking the `code`
  * @param locales
  */
+export function getAllCodes(locales: Locales): string[] {
+	const result: string[] = [];
+	for (const loopLocale of locales) {
+		if (typeof loopLocale === 'string') {
+			result.push(loopLocale);
+		} else {
+			result.push(...loopLocale.codes);
+		}
+	}
+	return result
+}
+
 export function toCodes(locales: Locales): string[] {
 	return locales.map((loopLocale) => {
 		if (typeof loopLocale === 'string') {
@@ -239,6 +251,7 @@ export function toCodes(locales: Locales): string[] {
 	});
 }
 
+
 /**
  * It returns the array of paths
  * @param locales

packages/astro/src/i18n/utils.ts

@@ -1,6 +1,6 @@
 import type { SSRManifest } from '../core/app/types.js';
 import type { AstroConfig, Locales } from '../types/public/config.js';
-import { normalizeTheLocale, toCodes } from './index.js';
+import { normalizeTheLocale, getAllCodes } from './index.js';
 
 type BrowserLocale = {
 	locale: string;
@@ -62,7 +62,7 @@ export function parseLocale(header: string): BrowserLocale[] {
 }
 
 function sortAndFilterLocales(browserLocaleList: BrowserLocale[], locales: Locales) {
-	const normalizedLocales = toCodes(locales).map(normalizeTheLocale);
+	const normalizedLocales = getAllCodes(locales).map(normalizeTheLocale);
 	return browserLocaleList
 		.filter((browserLocale) => {
 			if (browserLocale.locale !== '*') {
@@ -96,11 +96,13 @@ export function computePreferredLocale(request: Request, locales: Locales): stri
 				if (typeof currentLocale === 'string') {
 					if (normalizeTheLocale(currentLocale) === normalizeTheLocale(firstResult.locale)) {
 						result = currentLocale;
+						break;
 					}
 				} else {
 					for (const currentCode of currentLocale.codes) {
 						if (normalizeTheLocale(currentCode) === normalizeTheLocale(firstResult.locale)) {
-							result = currentLocale.path;
+							result = currentCode;
+							break;
 						}
 					}
 				}
@@ -119,14 +121,7 @@ export function computePreferredLocaleList(request: Request, locales: Locales):
 
 		// SAFETY: bang operator is safe because checked by the previous condition
 		if (browserLocaleList.length === 1 && browserLocaleList.at(0)!.locale === '*') {
-			return locales.map((locale) => {
-				if (typeof locale === 'string') {
-					return locale;
-				} else {
-					// SAFETY: codes is never empty
-					return locale.codes.at(0)!;
-				}
-			});
+			return getAllCodes(locales);
 		} else if (browserLocaleList.length > 0) {
 			for (const browserLocale of browserLocaleList) {
 				for (const loopLocale of locales) {
@@ -137,7 +132,7 @@ export function computePreferredLocaleList(request: Request, locales: Locales):
 					} else {
 						for (const code of loopLocale.codes) {
 							if (code === browserLocale.locale) {
-								result.push(loopLocale.path);
+								result.push(code);
 							}
 						}
 					}

packages/astro/test/fixtures/i18n-routing-redirect-preferred-language/astro.config.mjs

@@ -4,7 +4,14 @@ export default defineConfig({
 	i18n: {
 		defaultLocale: 'en',
 		locales: [
-			'en', 'pt', 'it'
+			'en', 
+			'pt', 
+			'it',
+			{
+				path: "zh-Hant",
+				codes: ["zh-HK", "zh-TW"]
+			}
+			
 		]
 	}
 })

packages/astro/test/i18n-routing.test.js

@@ -1701,6 +1701,20 @@ describe('[SSR] i18n routing', () => {
 			assert.equal(text.includes('Locale list: en, pt, it'), true);
 		});
 
+
+		it('should render the preferred locale when a locale is configured with codes', async () => {
+			let request = new Request('http://example.com/preferred-locale', {
+				headers: {
+					'Accept-Language': 'es-SP;q=0.9,es;q=0.8,en-US;q=0.7,en;q=0.6',
+				},
+			});
+			let response = await app.render(request);
+			const text = await response.text();
+			assert.equal(response.status, 200);
+			assert.equal(text.includes('Locale: es-SP'), true);
+			assert.equal(text.includes('Locale list: es-SP, es, en'), true);
+		});
+
 		describe('in case the configured locales use underscores', () => {
 			before(async () => {
 				fixture = await loadFixture({
@@ -1751,8 +1765,8 @@ describe('[SSR] i18n routing', () => {
 				let response = await app.render(request);
 				const text = await response.text();
 				assert.equal(response.status, 200);
-				assert.equal(text.includes('Locale: spanish'), true);
-				assert.equal(text.includes('Locale list: spanish'), true);
+				assert.equal(text.includes('Locale: es'), true);
+				assert.equal(text.includes('Locale list: es'), true);
 			});
 		});
 	});