fix(i18n): generate fallbacks for pages with filenames containing locale keys (#14690)

fredriknorlin · web-flow · commit ae7197d35676 · 2025-11-14T08:37:05.000Z
diff --git a/.changeset/ten-masks-attend.md b/.changeset/ten-masks-attend.md
@@ -0,0 +1,5 @@
+---
+'astro': patch
+---
+
+Fixes a bug where Astro's i18n fallback system with `fallbackType: 'rewrite'` would not generate fallback files for pages whose filename started with a locale key.
diff --git a/packages/astro/src/core/routing/manifest/create.ts b/packages/astro/src/core/routing/manifest/create.ts
@@ -565,7 +565,7 @@ export async function createRoutesList(
 		const setRoutes = new Set(routes.filter((route) => route.type === 'page'));
 
 		// First loop
-		// We loop over the locales minus the default locale and add only the routes that contain `/<locale>`.
+		// We loop over all locales except the default, adding routes that include the locale as a path segment.
 		const filteredLocales = i18n.locales
 			.filter((loc) => {
 				if (typeof loc === 'string') {
@@ -581,7 +581,8 @@ export async function createRoutesList(
 			});
 		for (const locale of filteredLocales) {
 			for (const route of setRoutes) {
-				if (!route.route.includes(`/${locale}`)) {
+				const hasLocaleInRoute = route.route.split('/').includes(locale);
+				if (!hasLocaleInRoute) {
 					continue;
 				}
 				const currentRoutes = routesByLocale.get(locale);
diff --git a/packages/astro/test/fixtures/i18n-routing-fallback-rewrite-filename/astro.config.mjs b/packages/astro/test/fixtures/i18n-routing-fallback-rewrite-filename/astro.config.mjs
@@ -0,0 +1,14 @@
+import { defineConfig} from "astro/config";
+
+export default defineConfig({
+  i18n: {
+    locales: ['en', 'de'],
+    defaultLocale: 'en',
+    routing: {
+      fallbackType: 'rewrite',
+    },
+    fallback: {
+      de: 'en',
+    },
+  },
+});
diff --git a/packages/astro/test/fixtures/i18n-routing-fallback-rewrite-filename/package.json b/packages/astro/test/fixtures/i18n-routing-fallback-rewrite-filename/package.json
@@ -0,0 +1,8 @@
+{
+  "name": "@test/i18n-routing-fallback-rewrite-filename",
+  "version": "0.0.0",
+  "private": true,
+  "dependencies": {
+    "astro": "workspace:*"
+  }
+}
diff --git a/packages/astro/test/fixtures/i18n-routing-fallback-rewrite-filename/src/pages/denmark.astro b/packages/astro/test/fixtures/i18n-routing-fallback-rewrite-filename/src/pages/denmark.astro
@@ -0,0 +1,3 @@
+---
+---
+<span id="page">Denmark</span>
diff --git a/packages/astro/test/fixtures/i18n-routing-fallback-rewrite-filename/src/pages/destinations/denmark.astro b/packages/astro/test/fixtures/i18n-routing-fallback-rewrite-filename/src/pages/destinations/denmark.astro
@@ -0,0 +1,3 @@
+---
+---
+<span id="page">Destination: Denmark</span>
diff --git a/packages/astro/test/fixtures/i18n-routing-fallback-rewrite-filename/src/pages/destinations/index.astro b/packages/astro/test/fixtures/i18n-routing-fallback-rewrite-filename/src/pages/destinations/index.astro
@@ -0,0 +1,3 @@
+---
+---
+<span id="page">Destination: Index</span>
diff --git a/packages/astro/test/fixtures/i18n-routing-fallback-rewrite-filename/src/pages/destinations/norway.astro b/packages/astro/test/fixtures/i18n-routing-fallback-rewrite-filename/src/pages/destinations/norway.astro
@@ -0,0 +1,3 @@
+---
+---
+<span id="page">Destination: Norway</span>
diff --git a/packages/astro/test/fixtures/i18n-routing-fallback-rewrite-filename/src/pages/index.astro b/packages/astro/test/fixtures/i18n-routing-fallback-rewrite-filename/src/pages/index.astro
@@ -0,0 +1,3 @@
+---
+---
+<span id="page">Index</span>
diff --git a/packages/astro/test/fixtures/i18n-routing-fallback-rewrite-filename/src/pages/norway.astro b/packages/astro/test/fixtures/i18n-routing-fallback-rewrite-filename/src/pages/norway.astro
@@ -0,0 +1,3 @@
+---
+---
+<span id="page">Norway</span>
diff --git a/packages/astro/test/fixtures/i18n-routing-fallback-rewrite-filename/src/pages/trade/denmark.astro b/packages/astro/test/fixtures/i18n-routing-fallback-rewrite-filename/src/pages/trade/denmark.astro
@@ -0,0 +1,3 @@
+---
+---
+<span id="page">Trade: Denmark</span>
diff --git a/packages/astro/test/fixtures/i18n-routing-fallback-rewrite-filename/src/pages/trade/index.astro b/packages/astro/test/fixtures/i18n-routing-fallback-rewrite-filename/src/pages/trade/index.astro
@@ -0,0 +1,3 @@
+---
+---
+<span id="page">Trade: Index</span>
diff --git a/packages/astro/test/fixtures/i18n-routing-fallback-rewrite-filename/src/pages/trade/norway.astro b/packages/astro/test/fixtures/i18n-routing-fallback-rewrite-filename/src/pages/trade/norway.astro
@@ -0,0 +1,3 @@
+---
+---
+<span id="page">Trade: Norway</span>
diff --git a/packages/astro/test/i18n-routing.test.js b/packages/astro/test/i18n-routing.test.js
@@ -1252,6 +1252,82 @@ describe('[SSG] i18n routing', () => {
 		});
 	});
 
+	describe('i18n routing with fallback rewrite with locale-like filenames', () => {
+		/** @type {import('./test-utils').Fixture} */
+		let fixture;
+
+		before(async () => {
+			fixture = await loadFixture({
+				root: './fixtures/i18n-routing-fallback-rewrite-filename/',
+			});
+			await fixture.build();
+		});
+
+		it('should generate fallback files for pages with without locale-like filenames', async () => {
+			let html = await fixture.readFile('/norway/index.html');
+			assert.equal(html.includes('Norway'), true);
+
+			html = await fixture.readFile('/de/norway/index.html');
+			assert.equal(html.includes('Norway'), true);
+		});
+
+		it('should generate fallback files for pages with locale-like filenames starting with locale', async () => {
+			let html = await fixture.readFile('/denmark/index.html');
+			assert.equal(html.includes('Denmark'), true);
+
+			html = await fixture.readFile('/de/denmark/index.html');
+			assert.equal(html.includes('Denmark'), true);
+		});
+
+		it('should generate fallback files for pages with locale-like filenames containing locale', async () => {
+			let html = await fixture.readFile('/index.html');
+			assert.equal(html.includes('Index'), true);
+
+			html = await fixture.readFile('/de/index.html');
+			assert.equal(html.includes('Index'), true);
+		});
+
+		it('should generate fallback files for pages in subdirectories with locale-like name starting with locale', async () => {
+			let html = await fixture.readFile('/destinations/denmark/index.html');
+			assert.equal(html.includes('Destination: Denmark'), true);
+
+			html = await fixture.readFile('/de/destinations/denmark/index.html');
+			assert.equal(html.includes('Destination: Denmark'), true);
+
+			html = await fixture.readFile('/destinations/index.html');
+			assert.equal(html.includes('Destination: Index'), true);
+
+			html = await fixture.readFile('/de/destinations/index.html');
+			assert.equal(html.includes('Destination: Index'), true);
+
+			html = await fixture.readFile('/destinations/norway/index.html');
+			assert.equal(html.includes('Destination: Norway'), true);
+
+			html = await fixture.readFile('/de/destinations/norway/index.html');
+			assert.equal(html.includes('Destination: Norway'), true);
+		});
+
+		it('should generate fallback files for pages in subdirectories with locale-like name containing locale', async () => {
+			let html = await fixture.readFile('/trade/denmark/index.html');
+			assert.equal(html.includes('Trade: Denmark'), true);
+
+			html = await fixture.readFile('/de/trade/denmark/index.html');
+			assert.equal(html.includes('Trade: Denmark'), true);
+
+			html = await fixture.readFile('/trade/index.html');
+			assert.equal(html.includes('Trade: Index'), true);
+
+			html = await fixture.readFile('/de/trade/index.html');
+			assert.equal(html.includes('Trade: Index'), true);
+
+			html = await fixture.readFile('/trade/norway/index.html');
+			assert.equal(html.includes('Trade: Norway'), true);
+
+			html = await fixture.readFile('/de/trade/norway/index.html');
+			assert.equal(html.includes('Trade: Norway'), true);
+		});
+	});
+
 	describe('current locale', () => {
 		describe('with [prefix-other-locales]', () => {
 			/** @type {import('./test-utils').Fixture} */
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml

-Original file line number
+Diff line change
@@ @@ -0,0 +1,5 @@ @@
 +---
 +'astro': patch
 +---
++
 +Fixes a bug where Astro's i18n fallback system with `fallbackType: 'rewrite'` would not generate fallback files for pages whose filename started with a locale key.
Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,3 @@`
	`1`	`+---`
	`2`	`+---`
	`3`	`+<span id="page">Denmark</span>`