From 2010f9914b34ff2881362865109f1af94687e991 Mon Sep 17 00:00:00 2001
From: JJ Kasper <jj@jjsweb.site>
Date: Mon, 27 Jan 2020 12:03:28 -0600
Subject: [PATCH 1/3] Enable static 404 config to allow static 404 page when
 available

---
 packages/next/next-server/server/config.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/next/next-server/server/config.ts b/packages/next/next-server/server/config.ts
index fb47ecb9df8743a..5fe42e75d34340d 100644
--- a/packages/next/next-server/server/config.ts
+++ b/packages/next/next-server/server/config.ts
@@ -52,7 +52,7 @@ const defaultConfig: { [key: string]: any } = {
     reactMode: 'legacy',
     workerThreads: false,
     basePath: '',
-    static404: false,
+    static404: true,
   },
   future: {
     excludeDefaultMomentLocales: false,

From 32984098b051b533611a443ef22eb10f1b131235 Mon Sep 17 00:00:00 2001
From: JJ Kasper <jj@jjsweb.site>
Date: Mon, 27 Jan 2020 12:09:14 -0600
Subject: [PATCH 2/3] Update static 404 suite

---
 test/integration/static-404/test/index.test.js | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/test/integration/static-404/test/index.test.js b/test/integration/static-404/test/index.test.js
index 5e466ce9c808079..7d0fde74ad429b7 100644
--- a/test/integration/static-404/test/index.test.js
+++ b/test/integration/static-404/test/index.test.js
@@ -20,7 +20,6 @@ const static404 = join(
 const appPage = join(appDir, 'pages/_app.js')
 const errorPage = join(appDir, 'pages/_error.js')
 const buildId = `generateBuildId: () => 'test-id'`
-const experimentalConfig = `experimental: { static404: true }`
 let app
 let appPort
 
@@ -34,7 +33,10 @@ describe('Static 404 page', () => {
 
   describe('With config disabled', () => {
     it('should not have exported static 404 page', async () => {
-      await fs.writeFile(nextConfig, `module.exports = { ${buildId} }`)
+      await fs.writeFile(
+        nextConfig,
+        `module.exports = { ${buildId}, experimental: { static404: false } }`
+      )
       await nextBuild(appDir)
       expect(await fs.exists(static404)).toBe(false)
     })
@@ -42,10 +44,7 @@ describe('Static 404 page', () => {
 
   describe('With config enabled', () => {
     beforeEach(() =>
-      fs.writeFile(
-        nextConfig,
-        `module.exports = { ${buildId}, ${experimentalConfig} }`
-      )
+      fs.writeFile(nextConfig, `module.exports = { ${buildId} }`)
     )
 
     it('should export 404 page without custom _error', async () => {

From 0fe0e67b9259f04a516c84db537c3cb39870aa0c Mon Sep 17 00:00:00 2001
From: JJ Kasper <jj@jjsweb.site>
Date: Mon, 27 Jan 2020 13:31:23 -0600
Subject: [PATCH 3/3] Fix invalid params test case

---
 packages/next/next-server/server/next-server.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/next/next-server/server/next-server.ts b/packages/next/next-server/server/next-server.ts
index e2ac323dce02887..e48fd43cd25b353 100644
--- a/packages/next/next-server/server/next-server.ts
+++ b/packages/next/next-server/server/next-server.ts
@@ -1084,7 +1084,7 @@ export default class Server {
     let result: null | LoadComponentsReturnType = null
 
     // use static 404 page if available and is 404 response
-    if (this.nextConfig.experimental.static404 && err === null) {
+    if (this.nextConfig.experimental.static404 && res.statusCode === 404) {
       try {
         result = await this.findPageComponents('/_errors/404')
       } catch (err) {