fix: data route rewrite for i18n root route (#2002)

* fix: data route rewrite for i18n root route

* chore: update snapshots for new rewrite

Author: orinokai

packages/runtime/src/helpers/utils.ts

@@ -74,7 +74,7 @@ export const generateNetlifyRoutes = ({
 }) => [...(withData ? toNetlifyRoute(dataRoute) : []), ...toNetlifyRoute(route)]
 
 export const routeToDataRoute = (route: string, buildId: string, locale?: string) =>
-  `/_next/data/${buildId}${locale ? `/${locale}` : ''}${route === '/' ? '/index' : route}.json`
+  `/_next/data/${buildId}${locale ? `/${locale}` : ''}${route === '/' ? (locale ? '' : '/index') : route}.json`
 
 // Default locale is served from root, not localized
 export const localizeRoute = (route: string, locale: string, defaultLocale: string) =>

test/__snapshots__/index.spec.js.snap

@@ -658,6 +658,12 @@ Array [
     "status": 200,
     "to": "/.netlify/builders/_ipx",
   },
+  Object {
+    "force": true,
+    "from": "/_next/data/build-id/en.json",
+    "status": 200,
+    "to": "/.netlify/builders/___netlify-odb-handler",
+  },
   Object {
     "force": false,
     "from": "/_next/data/build-id/en/500.json",
@@ -844,12 +850,6 @@ Array [
     "status": 200,
     "to": "/.netlify/functions/___netlify-handler",
   },
-  Object {
-    "force": true,
-    "from": "/_next/data/build-id/en/index.json",
-    "status": 200,
-    "to": "/.netlify/builders/___netlify-odb-handler",
-  },
   Object {
     "force": false,
     "from": "/_next/data/build-id/en/layouts.json",