From 42ea5aa18c90457a372d6a93270c0bffc49da3b2 Mon Sep 17 00:00:00 2001
From: JJ Kasper <jj@jjsweb.site>
Date: Wed, 16 Jun 2021 14:45:12 -0500
Subject: [PATCH] Fix long URLs causing 400s with dynamic routes/rewrites

---
 packages/next/lib/file-exists.ts                     |  2 +-
 test/integration/custom-routes/test/index.test.js    | 11 +++++++++++
 .../dynamic-routing/pages/dash/[hello-world].js      |  4 +++-
 test/integration/dynamic-routing/test/index.test.js  | 12 ++++++++++++
 .../production/pages/invalid-param/[slug].js         |  2 +-
 5 files changed, 28 insertions(+), 3 deletions(-)

diff --git a/packages/next/lib/file-exists.ts b/packages/next/lib/file-exists.ts
index fc60cdcf8e30f..b3e49b1624a8b 100644
--- a/packages/next/lib/file-exists.ts
+++ b/packages/next/lib/file-exists.ts
@@ -16,7 +16,7 @@ export async function fileExists(
     }
     return true
   } catch (err) {
-    if (err.code === 'ENOENT') {
+    if (err.code === 'ENOENT' || err.code === 'ENAMETOOLONG') {
       return false
     }
     throw err
diff --git a/test/integration/custom-routes/test/index.test.js b/test/integration/custom-routes/test/index.test.js
index 9453a19eb5fd5..3fce6591dedb3 100644
--- a/test/integration/custom-routes/test/index.test.js
+++ b/test/integration/custom-routes/test/index.test.js
@@ -39,6 +39,17 @@ let appPort
 let app
 
 const runTests = (isDev = false) => {
+  it('should support long URLs for rewrites', async () => {
+    const res = await fetchViaHTTP(
+      appPort,
+      '/catchall-rewrite/a9btBxtHQALZ6cxfuj18X6OLGNSkJVzrOXz41HG4QwciZfn7ggRZzPx21dWqGiTBAqFRiWvVNm5ko2lpyso5jtVaXg88dC1jKfqI2qmIcdeyJat8xamrIh2LWnrYRrsBcoKfQU65KHod8DPANuzPS3fkVYWlmov05GQbc82HwR1exOvPVKUKb5gBRWiN0WOh7hN4QyezIuq3dJINAptFQ6m2bNGjYACBRk4MOSHdcQG58oq5Ch7luuqrl9EcbWSa'
+    )
+
+    const html = await res.text()
+    expect(res.status).toBe(200)
+    expect(html).toContain('/with-params')
+  })
+
   it('should resolveHref correctly navigating through history', async () => {
     const browser = await webdriver(appPort, '/')
     await browser.eval('window.beforeNav = 1')
diff --git a/test/integration/dynamic-routing/pages/dash/[hello-world].js b/test/integration/dynamic-routing/pages/dash/[hello-world].js
index 0957a987fc2f2..2468ab1dc7171 100644
--- a/test/integration/dynamic-routing/pages/dash/[hello-world].js
+++ b/test/integration/dynamic-routing/pages/dash/[hello-world].js
@@ -1 +1,3 @@
-export default () => 'hi'
+export default function Page(props) {
+  return 'hi'
+}
diff --git a/test/integration/dynamic-routing/test/index.test.js b/test/integration/dynamic-routing/test/index.test.js
index ac8f7842a0d60..754dc8e366f31 100644
--- a/test/integration/dynamic-routing/test/index.test.js
+++ b/test/integration/dynamic-routing/test/index.test.js
@@ -30,6 +30,18 @@ const appDir = join(__dirname, '../')
 const buildIdPath = join(appDir, '.next/BUILD_ID')
 
 function runTests(dev) {
+  it('should support long URLs for dynamic routes', async () => {
+    const res = await fetchViaHTTP(
+      appPort,
+      '/dash/a9btBxtHQALZ6cxfuj18X6OLGNSkJVzrOXz41HG4QwciZfn7ggRZzPx21dWqGiTBAqFRiWvVNm5ko2lpyso5jtVaXg88dC1jKfqI2qmIcdeyJat8xamrIh2LWnrYRrsBcoKfQU65KHod8DPANuzPS3fkVYWlmov05GQbc82HwR1exOvPVKUKb5gBRWiN0WOh7hN4QyezIuq3dJINAptFQ6m2bNGjYACBRk4MOSHdcQG58oq5Ch7luuqrl9EcbWSa'
+    )
+
+    const html = await res.text()
+    expect(res.status).toBe(200)
+    expect(html).toContain('hi')
+    expect(html).toContain('/dash/[hello-world]')
+  })
+
   it('should handle only query on dynamic route', async () => {
     const browser = await webdriver(appPort, '/post-1')
 
diff --git a/test/integration/production/pages/invalid-param/[slug].js b/test/integration/production/pages/invalid-param/[slug].js
index 9f287061d65fc..36b5e610a9331 100644
--- a/test/integration/production/pages/invalid-param/[slug].js
+++ b/test/integration/production/pages/invalid-param/[slug].js
@@ -1,7 +1,7 @@
 import { useRouter } from 'next/router'
 
 export default function Page() {
-  return <p>hello {useRouter().query}</p>
+  return <p>hello {useRouter().query.slug}</p>
 }
 
 export const getServerSideProps = () => {