fix: Fix hard reload when using <Link /> in Next.js 15 (#1620)

packages/next-intl/rollup.config.js

@@ -2,6 +2,19 @@ import preserveDirectives from 'rollup-plugin-preserve-directives';
 import {getBuildConfig} from 'tools';
 import pkg from './package.json' with {type: 'json'};
 
+function rewriteBundle(regex, replaceFn) {
+  return {
+    name: 'rewrite-bundle',
+    generateBundle(options, bundle) {
+      for (const fileName of Object.keys(bundle)) {
+        const chunk = bundle[fileName];
+        const updatedCode = chunk.code.replace(regex, replaceFn);
+        chunk.code = updatedCode;
+      }
+    }
+  };
+}
+
 export default [
   ...getBuildConfig({
     input: {
@@ -34,7 +47,20 @@ export default [
       if (warning.code === 'MODULE_LEVEL_DIRECTIVE') return;
       warn(warning);
     },
-    plugins: [preserveDirectives()]
+    plugins: [
+      preserveDirectives(),
+
+      // Since we're writing our code with ESM, we have to import e.g. from
+      // `next/link.js`. While this can be used in production, since Next.js 15
+      // this somehow causes hard reloads when `next/link.js` is imported and
+      // used to link to another page. There might be some optimizations
+      // happening in the background that we can't control. Due to this, it
+      // seems safer to update imports to a version that doesn't have `.js`
+      // suffix and let the bundler optimize them.
+      rewriteBundle(/['"]next\/(\w+)\.js['"]/g, (match, p1) =>
+        match.replace(`next/${p1}.js`, `next/${p1}`)
+      )
+    ]
   }),
   ...getBuildConfig({
     env: ['development'],