enhance: cover re-exported gsp cases for runtime fallback (vercel#35326)

Cover re-exported gsp cases from vercel#35011

Author: huozhi

packages/next/build/entries.ts

@@ -144,7 +144,7 @@ export async function getPageRuntime(
       for (const node of body) {
         const { type, declaration } = node
         if (type === 'ExportDeclaration') {
-          // `export const config`
+          // Match `export const config`
           const valueNode = declaration?.declarations?.[0]
           if (valueNode?.id?.value === 'config') {
             const props = valueNode.init.properties
@@ -155,15 +155,30 @@ export async function getPageRuntime(
             pageRuntime =
               runtime === 'edge' || runtime === 'nodejs' ? runtime : pageRuntime
           } else if (declaration?.type === 'FunctionDeclaration') {
-            // `export function getStaticProps` and
-            // `export function getServerSideProps`
+            // Match `export function getStaticProps | getServerSideProps`
+            const identifier = declaration.identifier?.value
             if (
-              declaration.identifier?.value === 'getStaticProps' ||
-              declaration.identifier?.value === 'getServerSideProps'
+              identifier === 'getStaticProps' ||
+              identifier === 'getServerSideProps'
             ) {
               isRuntimeRequired = true
             }
           }
+        } else if (type === 'ExportNamedDeclaration') {
+          // Match `export { getStaticProps | getServerSideProps } <from '../..'>`
+          const { specifiers } = node
+          for (const specifier of specifiers) {
+            const { orig } = specifier
+            const hasDataFetchingExports =
+              specifier.type === 'ExportSpecifier' &&
+              orig?.type === 'Identifier' &&
+              (orig?.value === 'getStaticProps' ||
+                orig?.value === 'getServerSideProps')
+            if (hasDataFetchingExports) {
+              isRuntimeRequired = true
+              break
+            }
+          }
         }
       }
     } catch (err) {}

test/unit/fixtures/page-runtime/fallback-re-export-gsp.js

@@ -0,0 +1,5 @@
+export { getStaticProps } from '../lib/utils'
+
+export default function ImportGsp({ gsp }) {
+  return `import-${gsp}`
+}

test/unit/fixtures/page-runtime/fallback.js renamed to test/unit/fixtures/page-runtime/fallback-with-gsp.js

@@ -24,10 +24,20 @@ describe('parse page runtime config', () => {
     )
     expect(runtime).toBe(undefined)
   })
+})
+
+describe('fallback to the global runtime configuration', () => {
+  it('should fallback when gSP is defined and exported', async () => {
+    const runtime = await getPageRuntime(
+      join(fixtureDir, 'page-runtime/fallback-with-gsp.js'),
+      'edge'
+    )
+    expect(runtime).toBe('edge')
+  })
 
-  it('should fallback to the global runtime configuration if a runtime is needed', async () => {
+  it('should fallback when gSP is re-exported from other module', async () => {
     const runtime = await getPageRuntime(
-      join(fixtureDir, 'page-runtime/fallback.js'),
+      join(fixtureDir, 'page-runtime/fallback-re-export-gsp.js'),
       'edge'
     )
     expect(runtime).toBe('edge')