[test] Robuster extraction off CSS sources in Flight chunks (#80243)

Author: eps1lon

test/e2e/app-dir/app-css/index.test.ts

@@ -1,8 +1,6 @@
 import { nextTestSetup } from 'e2e-utils'
 import { check } from 'next-test-utils'
 
-const isPPREnabledByDefault = process.env.__NEXT_EXPERIMENTAL_PPR === 'true'
-
 describe('app dir - css', () => {
   const { next, isNextDev, skipped } = nextTestSetup({
     files: __dirname,
@@ -490,47 +488,31 @@ describe('app dir - css', () => {
             // Even if it's deduped by Float, it should still only be included once in the payload.
 
             const matches = initialHtml
-              .match(/\/_next\/static\/css\/.+?\.css/g)
               // The same css chunk could be split into 2 RSC script
-              // normalize "/_next/static/css/app/\"])</script><script>self.__next_f.push([1,\"not-found.css"
+              // e.g.
+              // "/_next/static/css/app/"])</script><script>self.__next_f.push([1,"not-found.css"
+              // "/_next/stati"])</script><script>self.__next_f.push([1,"c/css/app/not-found.css?v=1749205445967"
               // to "/_next/static/css/app/not-found.css"
-              .map((href) =>
-                href.replace('"])</script><script>self.__next_f.push([1,"', '')
-              )
+              .replaceAll('"])</script><script>self.__next_f.push([1,"', '')
+              .match(/\/_next\/static\/css\/.+?\.css/g)
               .sort()
 
             // Heavy on testing React implementation details.
             // Assertions may change often but what needs to be checked on change is if styles are needlessly duplicated in Flight data
             // There are 3 matches, one for the rendered <link> (HTML), one for Float preload (Flight) and one for the <link> inside Flight payload.
             // And there is one match for the not found style
-            if (isPPREnabledByDefault) {
-              expect(matches).toEqual([
-                // may be split across chunks when we bump React
-                '/_next/static/css/app/css/css-duplicate-2/layout.css',
-                '/_next/static/css/app/css/css-duplicate-2/layout.css',
-                '/_next/static/css/app/css/css-duplicate-2/layout.css',
-                '/_next/static/css/app/css/layout.css',
-                '/_next/static/css/app/css/layout.css',
-                '/_next/static/css/app/css/layout.css',
-                '/_next/static/css/app/layout.css',
-                '/_next/static/css/app/layout.css',
-                '/_next/static/css/app/layout.css',
-                '/_next/static/css/app/not-found.css',
-              ])
-            } else {
-              expect(matches).toEqual([
-                '/_next/static/css/app/css/css-duplicate-2/layout.css',
-                '/_next/static/css/app/css/css-duplicate-2/layout.css',
-                '/_next/static/css/app/css/css-duplicate-2/layout.css',
-                '/_next/static/css/app/css/layout.css',
-                '/_next/static/css/app/css/layout.css',
-                '/_next/static/css/app/css/layout.css',
-                '/_next/static/css/app/layout.css',
-                '/_next/static/css/app/layout.css',
-                '/_next/static/css/app/layout.css',
-                '/_next/static/css/app/not-found.css',
-              ])
-            }
+            expect(matches).toEqual([
+              '/_next/static/css/app/css/css-duplicate-2/layout.css',
+              '/_next/static/css/app/css/css-duplicate-2/layout.css',
+              '/_next/static/css/app/css/css-duplicate-2/layout.css',
+              '/_next/static/css/app/css/layout.css',
+              '/_next/static/css/app/css/layout.css',
+              '/_next/static/css/app/css/layout.css',
+              '/_next/static/css/app/layout.css',
+              '/_next/static/css/app/layout.css',
+              '/_next/static/css/app/layout.css',
+              '/_next/static/css/app/not-found.css',
+            ])
           }
         })