From 59a1f7bae03b8c3b74a5a1718de9404d27e47c5d Mon Sep 17 00:00:00 2001
From: Daniel Roe <daniel@roe.dev>
Date: Tue, 14 Feb 2023 22:22:53 +0000
Subject: [PATCH] perf(nuxt): allow tree-shaking empty meta from build (#19032)

---
 packages/nuxt/src/pages/page-meta.ts | 4 ++--
 packages/nuxt/src/pages/utils.ts     | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/packages/nuxt/src/pages/page-meta.ts b/packages/nuxt/src/pages/page-meta.ts
index c644b52b78b..83819845338 100644
--- a/packages/nuxt/src/pages/page-meta.ts
+++ b/packages/nuxt/src/pages/page-meta.ts
@@ -16,7 +16,7 @@ export interface PageMetaPluginOptions {
 }
 
 const CODE_EMPTY = `
-const __nuxt_page_meta = {}
+const __nuxt_page_meta = null
 export default __nuxt_page_meta
 `
 
@@ -138,7 +138,7 @@ export const PageMetaPlugin = createUnplugin((options: PageMetaPluginOptions) =>
 
           const meta = node.arguments[0] as Expression & { start: number, end: number }
 
-          let contents = `const __nuxt_page_meta = ${code!.slice(meta.start, meta.end) || '{}'}\nexport default __nuxt_page_meta` + (options.dev ? CODE_HMR : '')
+          let contents = `const __nuxt_page_meta = ${code!.slice(meta.start, meta.end) || 'null'}\nexport default __nuxt_page_meta` + (options.dev ? CODE_HMR : '')
 
           function addImport (name: string | false) {
             if (name && importMap.has(name)) {
diff --git a/packages/nuxt/src/pages/utils.ts b/packages/nuxt/src/pages/utils.ts
index 8c364e98fcf..946b67b5b0d 100644
--- a/packages/nuxt/src/pages/utils.ts
+++ b/packages/nuxt/src/pages/utils.ts
@@ -264,7 +264,7 @@ export function normalizeRoutes (routes: NuxtPage[], metaImports: Set<string> =
         name: `${metaImportName}?.name ?? ${page.name ? JSON.stringify(page.name) : 'undefined'}`,
         path: `${metaImportName}?.path ?? ${JSON.stringify(page.path)}`,
         children: page.children ? normalizeRoutes(page.children, metaImports).routes : [],
-        meta: page.meta ? `{...(${metaImportName} || {}), ...${JSON.stringify(page.meta)}}` : metaImportName,
+        meta: page.meta ? `{...(${metaImportName} || {}), ...${JSON.stringify(page.meta)}}` : `${metaImportName} || {}`,
         alias: aliasCode,
         redirect: page.redirect ? JSON.stringify(page.redirect) : `${metaImportName}?.redirect || undefined`,
         component: genDynamicImport(file, { interopDefault: true })