From 0ed08d8dfef5c4252b44baea8c9ba5fd954908b6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Hannes=20Born=C3=B6?= <hannes.borno@vercel.com>
Date: Wed, 7 Sep 2022 16:01:58 +0200
Subject: [PATCH] Dev server can recover from wrong runtime config

---
 .../build/analysis/get-page-static-info.ts    | 13 ++--
 packages/next/server/dev/hot-reloader.ts      |  1 +
 packages/next/server/dev/next-dev-server.ts   |  1 +
 .../server/dev/on-demand-entry-handler.ts     |  1 +
 test/e2e/switchable-runtime/index.test.ts     | 68 +++++++++++++++++++
 .../pages/invalid-runtime.js                  |  3 +
 6 files changed, 81 insertions(+), 6 deletions(-)
 create mode 100644 test/e2e/switchable-runtime/pages/invalid-runtime.js

diff --git a/packages/next/build/analysis/get-page-static-info.ts b/packages/next/build/analysis/get-page-static-info.ts
index cc18cc8d743a8..e702ee4fbb81c 100644
--- a/packages/next/build/analysis/get-page-static-info.ts
+++ b/packages/next/build/analysis/get-page-static-info.ts
@@ -226,21 +226,22 @@ export async function getPageStaticInfo(params: {
     }
 
     if (
-      typeof config.runtime !== 'string' &&
-      typeof config.runtime !== 'undefined'
+      typeof config.runtime !== 'undefined' &&
+      !isServerRuntime(config.runtime)
     ) {
-      throw new Error(`Provided runtime `)
-    } else if (!isServerRuntime(config.runtime)) {
       const options = Object.values(SERVER_RUNTIME).join(', ')
       if (typeof config.runtime !== 'string') {
-        throw new Error(
+        Log.error(
           `The \`runtime\` config must be a string. Please leave it empty or choose one of: ${options}`
         )
       } else {
-        throw new Error(
+        Log.error(
           `Provided runtime "${config.runtime}" is not supported. Please leave it empty or choose one of: ${options}`
         )
       }
+      if (!isDev) {
+        process.exit(1)
+      }
     }
 
     let runtime =
diff --git a/packages/next/server/dev/hot-reloader.ts b/packages/next/server/dev/hot-reloader.ts
index 8e1d195b7c7bc..7a7584b43bdc7 100644
--- a/packages/next/server/dev/hot-reloader.ts
+++ b/packages/next/server/dev/hot-reloader.ts
@@ -602,6 +602,7 @@ export default class HotReloader {
               ? await getPageStaticInfo({
                   pageFilePath: entryData.absolutePagePath,
                   nextConfig: this.config,
+                  isDev: true,
                 })
               : {}
 
diff --git a/packages/next/server/dev/next-dev-server.ts b/packages/next/server/dev/next-dev-server.ts
index 920a6264845d0..d360778905f41 100644
--- a/packages/next/server/dev/next-dev-server.ts
+++ b/packages/next/server/dev/next-dev-server.ts
@@ -369,6 +369,7 @@ export default class DevServer extends Server {
             pageFilePath: fileName,
             nextConfig: this.nextConfig,
             page: rootFile,
+            isDev: true,
           })
 
           if (isMiddlewareFile(rootFile)) {
diff --git a/packages/next/server/dev/on-demand-entry-handler.ts b/packages/next/server/dev/on-demand-entry-handler.ts
index a0a2fe8bf1718..1c752b7b296dd 100644
--- a/packages/next/server/dev/on-demand-entry-handler.ts
+++ b/packages/next/server/dev/on-demand-entry-handler.ts
@@ -632,6 +632,7 @@ export function onDemandEntryHandler({
         const staticInfo = await getPageStaticInfo({
           pageFilePath: pagePathData.absolutePagePath,
           nextConfig,
+          isDev: true,
         })
 
         const added = new Map<CompilerNameValues, ReturnType<typeof addEntry>>()
diff --git a/test/e2e/switchable-runtime/index.test.ts b/test/e2e/switchable-runtime/index.test.ts
index f21f94dba24bf..b9cef78198875 100644
--- a/test/e2e/switchable-runtime/index.test.ts
+++ b/test/e2e/switchable-runtime/index.test.ts
@@ -202,6 +202,74 @@ describe('Switchable runtime', () => {
           })
         }
       })
+
+      it('should not crash the dev server when invalid runtime is configured', async () => {
+        await check(
+          () => renderViaHTTP(next.url, '/invalid-runtime'),
+          /Hello from page without errors/
+        )
+
+        // Invalid runtime type
+        await next.patchFile(
+          'pages/invalid-runtime.js',
+          `
+          export default function Page() {
+            return <p>Hello from page with invalid type</p>
+          }
+          
+          export const config = {
+            runtime: 10,
+          }
+            `
+        )
+        await check(
+          () => renderViaHTTP(next.url, '/invalid-runtime'),
+          /Hello from page with invalid type/
+        )
+        expect(next.cliOutput).toInclude(
+          'error - The `runtime` config must be a string. Please leave it empty or choose one of:'
+        )
+
+        // Invalid runtime
+        await next.patchFile(
+          'pages/invalid-runtime.js',
+          `
+            export default function Page() {
+              return <p>Hello from page with invalid runtime</p>
+            }
+            
+            export const config = {
+              runtime: "asd"
+            }
+              `
+        )
+        await check(
+          () => renderViaHTTP(next.url, '/invalid-runtime'),
+          /Hello from page with invalid runtime/
+        )
+        expect(next.cliOutput).toInclude(
+          'error - Provided runtime "asd" is not supported. Please leave it empty or choose one of:'
+        )
+
+        // Fix the runtime
+        await next.patchFile(
+          'pages/invalid-runtime.js',
+          `
+        export default function Page() {
+          return <p>Hello from page without errors</p>
+        }
+        
+        export const config = {
+          runtime: 'experimental-edge',
+        }
+  
+        `
+        )
+        await check(
+          () => renderViaHTTP(next.url, '/invalid-runtime'),
+          /Hello from page without errors/
+        )
+      })
     })
   } else {
     describe('Switchable runtime (prod)', () => {
diff --git a/test/e2e/switchable-runtime/pages/invalid-runtime.js b/test/e2e/switchable-runtime/pages/invalid-runtime.js
new file mode 100644
index 0000000000000..17235157127be
--- /dev/null
+++ b/test/e2e/switchable-runtime/pages/invalid-runtime.js
@@ -0,0 +1,3 @@
+export default function Page() {
+  return <p>Hello from page without errors</p>
+}