return x-default also for sub pages when using as-needed

Author: amannn

Diff for: packages/next-intl/src/middleware/getAlternateLinksHeaderValue.test.tsx

@@ -184,7 +184,8 @@ describe.each([{basePath: undefined}, {basePath: '/base'}])(
         }).split(', ')
       ).toEqual([
         `<https://example.com${basePath}/en/about>; rel="alternate"; hreflang="en"`,
-        `<https://example.com${basePath}/es/about>; rel="alternate"; hreflang="es"`
+        `<https://example.com${basePath}/es/about>; rel="alternate"; hreflang="es"`,
+        `<https://example.com${basePath}/about>; rel="alternate"; hreflang="x-default"`
       ]);
     });
 

Diff for: packages/next-intl/src/middleware/getAlternateLinksHeaderValue.tsx

@@ -143,8 +143,7 @@ export default function getAlternateLinksHeaderValue<
   // Add x-default entry
   const shouldAddXDefault =
     // For domain-based routing there is no reasonable x-default
-    !routing.domains &&
-    (routing.localePrefix.mode !== 'always' || normalizedUrl.pathname === '/');
+    !routing.domains || routing.domains.length === 0;
   if (shouldAddXDefault) {
     const url = new URL(
       getLocalizedPathname(normalizedUrl.pathname, routing.defaultLocale),

Diff for: packages/next-intl/src/middleware/middleware.test.tsx

@@ -1400,35 +1400,42 @@ describe('prefix-based routing', () => {
         ]);
         expect(getLinks(createMockRequest('/en/about', 'en'))).toEqual([
           '<http://localhost:3000/en/about>; rel="alternate"; hreflang="en"',
-          '<http://localhost:3000/de/ueber>; rel="alternate"; hreflang="de"'
+          '<http://localhost:3000/de/ueber>; rel="alternate"; hreflang="de"',
+          '<http://localhost:3000/about>; rel="alternate"; hreflang="x-default"'
         ]);
         expect(getLinks(createMockRequest('/de/ueber', 'de'))).toEqual([
           '<http://localhost:3000/en/about>; rel="alternate"; hreflang="en"',
-          '<http://localhost:3000/de/ueber>; rel="alternate"; hreflang="de"'
+          '<http://localhost:3000/de/ueber>; rel="alternate"; hreflang="de"',
+          '<http://localhost:3000/about>; rel="alternate"; hreflang="x-default"'
         ]);
         expect(getLinks(createMockRequest('/en/users/1', 'en'))).toEqual([
           '<http://localhost:3000/en/users/1>; rel="alternate"; hreflang="en"',
-          '<http://localhost:3000/de/benutzer/1>; rel="alternate"; hreflang="de"'
+          '<http://localhost:3000/de/benutzer/1>; rel="alternate"; hreflang="de"',
+          '<http://localhost:3000/users/1>; rel="alternate"; hreflang="x-default"'
         ]);
         expect(getLinks(createMockRequest('/de/benutzer/1', 'de'))).toEqual([
           '<http://localhost:3000/en/users/1>; rel="alternate"; hreflang="en"',
-          '<http://localhost:3000/de/benutzer/1>; rel="alternate"; hreflang="de"'
+          '<http://localhost:3000/de/benutzer/1>; rel="alternate"; hreflang="de"',
+          '<http://localhost:3000/users/1>; rel="alternate"; hreflang="x-default"'
         ]);
         expect(
           getLinks(createMockRequest('/en/products/apparel/t-shirts', 'en'))
         ).toEqual([
           '<http://localhost:3000/en/products/apparel/t-shirts>; rel="alternate"; hreflang="en"',
-          '<http://localhost:3000/de/produkte/apparel/t-shirts>; rel="alternate"; hreflang="de"'
+          '<http://localhost:3000/de/produkte/apparel/t-shirts>; rel="alternate"; hreflang="de"',
+          '<http://localhost:3000/products/apparel/t-shirts>; rel="alternate"; hreflang="x-default"'
         ]);
         expect(
           getLinks(createMockRequest('/de/produkte/apparel/t-shirts', 'de'))
         ).toEqual([
           '<http://localhost:3000/en/products/apparel/t-shirts>; rel="alternate"; hreflang="en"',
-          '<http://localhost:3000/de/produkte/apparel/t-shirts>; rel="alternate"; hreflang="de"'
+          '<http://localhost:3000/de/produkte/apparel/t-shirts>; rel="alternate"; hreflang="de"',
+          '<http://localhost:3000/products/apparel/t-shirts>; rel="alternate"; hreflang="x-default"'
         ]);
         expect(getLinks(createMockRequest('/en/unknown', 'en'))).toEqual([
           '<http://localhost:3000/en/unknown>; rel="alternate"; hreflang="en"',
-          '<http://localhost:3000/de/unknown>; rel="alternate"; hreflang="de"'
+          '<http://localhost:3000/de/unknown>; rel="alternate"; hreflang="de"',
+          '<http://localhost:3000/unknown>; rel="alternate"; hreflang="x-default"'
         ]);
       });
 
@@ -1747,15 +1754,17 @@ describe('prefix-based routing', () => {
             '<http://localhost:3000/en/about>; rel="alternate"; hreflang="en"',
             '<http://localhost:3000/uk/about>; rel="alternate"; hreflang="en-gb"',
             '<http://localhost:3000/de/at/about>; rel="alternate"; hreflang="de-at"',
-            '<http://localhost:3000/br/about>; rel="alternate"; hreflang="pt"'
+            '<http://localhost:3000/br/about>; rel="alternate"; hreflang="pt"',
+            '<http://localhost:3000/about>; rel="alternate"; hreflang="x-default"'
           ]);
         });
 
         expect(getLinks(createMockRequest('/en/unknown'))).toEqual([
           '<http://localhost:3000/en/unknown>; rel="alternate"; hreflang="en"',
           '<http://localhost:3000/uk/unknown>; rel="alternate"; hreflang="en-gb"',
           '<http://localhost:3000/de/at/unknown>; rel="alternate"; hreflang="de-at"',
-          '<http://localhost:3000/br/unknown>; rel="alternate"; hreflang="pt"'
+          '<http://localhost:3000/br/unknown>; rel="alternate"; hreflang="pt"',
+          '<http://localhost:3000/unknown>; rel="alternate"; hreflang="x-default"'
         ]);
       });
     });
@@ -1880,15 +1889,17 @@ describe('prefix-based routing', () => {
             '<http://localhost:3000/en/about>; rel="alternate"; hreflang="en"',
             '<http://localhost:3000/uk/about>; rel="alternate"; hreflang="en-gb"',
             '<http://localhost:3000/de/at/ueber>; rel="alternate"; hreflang="de-at"',
-            '<http://localhost:3000/br/sobre>; rel="alternate"; hreflang="pt"'
+            '<http://localhost:3000/br/sobre>; rel="alternate"; hreflang="pt"',
+            '<http://localhost:3000/about>; rel="alternate"; hreflang="x-default"'
           ]);
         });
 
         expect(getLinks(createMockRequest('/en/unknown'))).toEqual([
           '<http://localhost:3000/en/unknown>; rel="alternate"; hreflang="en"',
           '<http://localhost:3000/uk/unknown>; rel="alternate"; hreflang="en-gb"',
           '<http://localhost:3000/de/at/unknown>; rel="alternate"; hreflang="de-at"',
-          '<http://localhost:3000/br/unknown>; rel="alternate"; hreflang="pt"'
+          '<http://localhost:3000/br/unknown>; rel="alternate"; hreflang="pt"',
+          '<http://localhost:3000/unknown>; rel="alternate"; hreflang="x-default"'
         ]);
       });
     });