From 40bc176792942f2a2ed29632edc84a3328734a92 Mon Sep 17 00:00:00 2001
From: Joe Haddad <joe.haddad@zeit.co>
Date: Fri, 11 Oct 2019 09:52:30 -0400
Subject: [PATCH 1/2] Remove static optimization from message This check does
 not pertain to automatic static optimization.

Closes https://github.com/zeit/next.js/issues/9042
---
 packages/next/build/index.ts                                    | 2 +-
 .../test/index.test.js                                          | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/next/build/index.ts b/packages/next/build/index.ts
index a7bd15cbdb757..d6c88ef87df26 100644
--- a/packages/next/build/index.ts
+++ b/packages/next/build/index.ts
@@ -411,7 +411,7 @@ export default async function build(dir: string, conf = null): Promise<void> {
 
   if (invalidPages.size > 0) {
     throw new Error(
-      `automatic static optimization failed: found page${
+      `Build optimization failed: found page${
         invalidPages.size === 1 ? '' : 's'
       } without a React Component as default export in \n${[...invalidPages]
         .map(pg => `pages${pg}`)
diff --git a/test/integration/invalid-page-automatic-static-optimization/test/index.test.js b/test/integration/invalid-page-automatic-static-optimization/test/index.test.js
index bcecd517ef7e7..847172a9a707a 100644
--- a/test/integration/invalid-page-automatic-static-optimization/test/index.test.js
+++ b/test/integration/invalid-page-automatic-static-optimization/test/index.test.js
@@ -11,7 +11,7 @@ describe('Invalid Page automatic static optimization', () => {
     const { stderr } = await nextBuild(appDir, [], { stderr: true })
 
     expect(stderr).toMatch(
-      /automatic static optimization failed: found pages without a React Component as default export in/
+      /Build optimization failed: found pages without a React Component as default export in/
     )
     expect(stderr).toMatch(/pages\/invalid/)
     expect(stderr).toMatch(/pages\/also-invalid/)

From 6cd8f743ed9e32aa5d04209047e6d5ec55f91d8e Mon Sep 17 00:00:00 2001
From: Joe Haddad <joe.haddad@zeit.co>
Date: Fri, 11 Oct 2019 10:02:54 -0400
Subject: [PATCH 2/2] Update help message

---
 errors/page-without-valid-component.md | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/errors/page-without-valid-component.md b/errors/page-without-valid-component.md
index 31f7e7f464837..9344b712c9dbb 100644
--- a/errors/page-without-valid-component.md
+++ b/errors/page-without-valid-component.md
@@ -2,8 +2,15 @@
 
 #### Why This Error Occurred
 
-While auto exporting a page a valid React Component wasn't found. This could mean you have a file in `pages` that exports something that is not a React Component.
+A page that does not export a valid React Component was found while analyzing the build output.
+
+This is a hard error because the page would error when rendered, and causes poor build performance.
 
 #### Possible Ways to Fix It
 
-Move any non-page files that don't export a React Component as the default export to a different folder like `components` or `lib`.
+Investigate the list of page(s) specified in the error message.
+For each, you'll want to check if the file is meant to be a page.
+
+If the file is not meant to be a page, and instead, is a shared component or file, move the file to a different folder like `components` or `lib`.
+
+If the file is meant to be a page, double check you have an `export default` with the React Component instead of an `export`. If you're already using `export default`, make sure the returned valid is a valid React Component.