Ensure skip normalize is handled correctly (#42642)

x-ref: [slack
thread](https://vercel.slack.com/archives/C01224Q5M99/p1667927545637489?thread_ts=1664536480.045539&cid=C01224Q5M99)
x-ref: vercel/vercel#8873

## Bug

- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a helpful link attached, see `contributing.md`

## Feature

- [ ] Implements an existing feature request or RFC. Make sure the
feature request has been accepted for implementation before opening a
PR.
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have a helpful link attached, see `contributing.md`

## Documentation / Examples

- [ ] Make sure the linting passes by running `pnpm build && pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing
doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)

packages/next/build/index.ts

@@ -761,6 +761,7 @@ export default async function build(
           header: typeof RSC
           varyHeader: typeof RSC_VARY_HEADER
         }
+        skipMiddlewareUrlNormalize?: boolean
       } = nextBuildSpan.traceChild('generate-routes-manifest').traceFn(() => {
         const sortedRoutes = getSortedRoutes([
           ...pageKeys.pages,
@@ -791,6 +792,8 @@ export default async function build(
             header: RSC,
             varyHeader: RSC_VARY_HEADER,
           },
+          skipMiddlewareUrlNormalize:
+            config.experimental.skipMiddlewareUrlNormalize,
         }
       })
 

test/e2e/skip-trailing-slash-redirect/app/middleware.js

@@ -1,16 +1,25 @@
 import { NextResponse } from 'next/server'
 
 export default function handler(req) {
+  console.log(req.nextUrl)
+
   if (req.nextUrl.pathname.startsWith('/_next/data/missing-id')) {
     console.log(`missing-id rewrite: ${req.nextUrl.toString()}`)
     return NextResponse.rewrite('https://example.vercel.sh')
   }
 
-  if (req.nextUrl.pathname === '/middleware-rewrite-with-slash') {
+  if (
+    req.nextUrl.pathname.startsWith('/_next/data') &&
+    req.nextUrl.pathname.endsWith('valid.json')
+  ) {
+    return NextResponse.rewrite('https://example.vercel.sh')
+  }
+
+  if (req.nextUrl.pathname.includes('/middleware-rewrite-with-slash')) {
     return NextResponse.rewrite(new URL('/another/', req.nextUrl))
   }
 
-  if (req.nextUrl.pathname === '/middleware-rewrite-without-slash') {
+  if (req.nextUrl.pathname.includes('/middleware-rewrite-without-slash')) {
     return NextResponse.rewrite(new URL('/another', req.nextUrl))
   }
 

test/e2e/skip-trailing-slash-redirect/index.test.ts

@@ -35,6 +35,21 @@ describe('skip-trailing-slash-redirect', () => {
     }
   })
 
+  it('should provide original _next/data URL with skipMiddlewareUrlNormalize', async () => {
+    const res = await fetchViaHTTP(
+      next.url,
+      `/_next/data/${next.buildId}/valid.json`,
+      undefined,
+      {
+        headers: {
+          'x-nextjs-data': '1',
+        },
+      }
+    )
+    expect(res.status).toBe(200)
+    expect(await res.text()).toContain('Example Domain')
+  })
+
   it('should allow response body from middleware with flag', async () => {
     const res = await fetchViaHTTP(next.url, '/middleware-response-body')
     expect(res.status).toBe(200)
@@ -88,15 +103,15 @@ describe('skip-trailing-slash-redirect', () => {
   it('should correct skip URL normalizing in middleware', async () => {
     let res = await fetchViaHTTP(
       next.url,
-      '/middleware-rewrite-with-slash',
+      `/_next/data/${next.buildId}/middleware-rewrite-with-slash.json`,
       undefined,
       { redirect: 'manual', headers: { 'x-nextjs-data': '1' } }
     )
     expect(res.headers.get('x-nextjs-rewrite').endsWith('/another/')).toBe(true)
 
     res = await fetchViaHTTP(
       next.url,
-      '/middleware-rewrite-without-slash',
+      `/_next/data/${next.buildId}/middleware-rewrite-without-slash.json`,
       undefined,
       { redirect: 'manual', headers: { 'x-nextjs-data': '1' } }
     )