Revert redundant RSC fetch patch removal

src/lib/rsc-route-normalization.test.ts

@@ -0,0 +1,84 @@
+import { describe, expect, it } from 'vitest'
+import { normalizeProxiedRscFetch } from '../pages/_layout'
+import { normalizeRscFetchUrl } from './rsc-route-normalization'
+
+const currentHref = 'https://docs.tempo.xyz/docs/guide/payments/send-a-payment'
+const origin = 'https://docs.tempo.xyz'
+
+describe('normalizeRscFetchUrl', () => {
+  it.each([
+    [
+      'keeps cross-origin RSC requests on the current origin',
+      'https://tempo.xyz/RSC/R/docs/guide/payments.txt?query=',
+      'https://docs.tempo.xyz/RSC/R/docs/guide/payments.txt?query=',
+    ],
+    [
+      'normalizes proxied developers route payloads',
+      'https://tempo.xyz/RSC/R/developers/docs/tools.txt?query=',
+      'https://docs.tempo.xyz/RSC/R/docs/tools.txt?query=',
+    ],
+    [
+      'normalizes the proxied developers root payload',
+      'https://tempo.xyz/RSC/R/developers.txt?query=',
+      'https://docs.tempo.xyz/RSC/R/_root.txt?query=',
+    ],
+    [
+      'preserves search and hash fragments',
+      'https://tempo.xyz/RSC/R/docs/tools.txt?query=abc#flight',
+      'https://docs.tempo.xyz/RSC/R/docs/tools.txt?query=abc#flight',
+    ],
+    [
+      'leaves non-RSC asset requests alone',
+      'https://tempo.xyz/assets/index.js',
+      'https://tempo.xyz/assets/index.js',
+    ],
+    ['leaves relative non-RSC requests alone', '/api/og?title=Tools', '/api/og?title=Tools'],
+  ])('%s', (_name, input, expected) => {
+    expect(normalizeRscFetchUrl(input, currentHref, origin)).toBe(expected)
+  })
+})
+
+describe('normalizeProxiedRscFetch', () => {
+  it.each([
+    [
+      'rewrites cross-origin RSC requests to the current origin',
+      'https://tempo.xyz/RSC/R/docs/tools.txt?query=',
+      'https://docs.tempo.xyz/RSC/R/docs/tools.txt?query=',
+    ],
+    [
+      'rewrites proxied developers RSC requests',
+      'https://tempo.xyz/RSC/R/developers/docs/tools.txt?query=',
+      'https://docs.tempo.xyz/RSC/R/docs/tools.txt?query=',
+    ],
+    [
+      'leaves non-RSC requests unchanged',
+      'https://tempo.xyz/assets/index.js',
+      'https://tempo.xyz/assets/index.js',
+    ],
+  ])('%s', async (_name, input, expected) => {
+    const requests: unknown[] = []
+    const fetch = (request: unknown) => {
+      requests.push(request)
+      return Promise.resolve(new Response())
+    }
+    Object.defineProperty(globalThis, 'window', {
+      configurable: true,
+      value: {
+        __tempoNormalizeProxiedRscFetch: false,
+        fetch,
+        location: {
+          href: currentHref,
+          origin,
+        },
+      },
+    })
+
+    try {
+      Function(normalizeProxiedRscFetch)()
+      await globalThis.window.fetch(input)
+      expect(requests).toEqual([expected])
+    } finally {
+      Reflect.deleteProperty(globalThis, 'window')
+    }
+  })
+})

src/lib/rsc-route-normalization.ts

@@ -0,0 +1,10 @@
+export function normalizeRscFetchUrl(url: string, currentHref: string, origin: string) {
+  const requestUrl = new URL(url, currentHref)
+  if (!requestUrl.pathname.startsWith('/RSC/R/')) return url
+
+  const pathname = requestUrl.pathname
+    .replace(/\/RSC\/R\/developers\.txt$/, '/RSC/R/_root.txt')
+    .replace(/\/RSC\/R\/developers\//, '/RSC/R/')
+
+  return new URL(pathname + requestUrl.search + requestUrl.hash, origin).toString()
+}

src/pages/_layout.tsx

@@ -1,5 +1,36 @@
 import type { PropsWithChildren } from 'react'
 
+export const normalizeProxiedRscFetch = `
+(() => {
+  if (window.__tempoNormalizeProxiedRscFetch) return;
+  window.__tempoNormalizeProxiedRscFetch = true;
+  const originalFetch = window.fetch.bind(window);
+  window.fetch = (input, init) => {
+    const url = typeof input === 'string'
+      ? input
+      : input instanceof URL
+        ? input.toString()
+        : input.url;
+    const requestUrl = new URL(url, window.location.href);
+    let rewritten = url;
+    if (requestUrl.pathname.startsWith('/RSC/R/')) {
+      const pathname = requestUrl.pathname
+        .replace(/\\/RSC\\/R\\/developers\\.txt$/, '/RSC/R/_root.txt')
+        .replace(/\\/RSC\\/R\\/developers\\//, '/RSC/R/');
+      rewritten = new URL(
+        pathname + requestUrl.search + requestUrl.hash,
+        window.location.origin,
+      ).toString();
+    }
+
+    if (rewritten === url) return originalFetch(input, init);
+    if (typeof input === 'string' || input instanceof URL) return originalFetch(rewritten, init);
+
+    return originalFetch(new Request(rewritten, input), init);
+  };
+})();
+`
+
 export default function Layout(
   props: PropsWithChildren<{
     path: string
@@ -15,6 +46,8 @@ export default function Layout(
         type="font/woff2"
         crossOrigin="anonymous"
       />
+      {/* biome-ignore lint/security/noDangerouslySetInnerHtml: static bootstrap must run before the RSC client bundle. */}
+      <script dangerouslySetInnerHTML={{ __html: normalizeProxiedRscFetch }} />
       {props.children}
     </>
   )

src/pages/docs/_layout.tsx

@@ -5,6 +5,7 @@ import DocsHeader from '../../components/DocsHeader'
 import DocsSectionNav from '../../components/DocsSectionNav'
 import DocsSidebarDrawer from '../../components/DocsSidebarDrawer'
 import { usePageSettled } from '../../lib/pageSettled'
+import { normalizeRscFetchUrl } from '../../lib/rsc-route-normalization'
 
 const Analytics = lazy(() =>
   import('@vercel/analytics/react').then((module) => ({ default: module.Analytics })),
@@ -17,6 +18,18 @@ const GoogleAnalytics = lazy(() => import('../../components/GoogleAnalytics'))
 const PostHogSetup = lazy(() => import('../../components/PostHogSetup'))
 
 if (typeof window !== 'undefined') {
+  const originalFetch = window.fetch.bind(window)
+  window.fetch = (input, init) => {
+    const url =
+      typeof input === 'string' ? input : input instanceof URL ? input.toString() : input.url
+    const rewritten = normalizeRscFetchUrl(url, window.location.href, window.location.origin)
+
+    if (rewritten === url) return originalFetch(input, init)
+    if (typeof input === 'string' || input instanceof URL) return originalFetch(rewritten, init)
+
+    return originalFetch(new Request(rewritten, input), init)
+  }
+
   window.addEventListener('vite:preloadError', (event) => {
     const key = `vite:preloadError:${(event as unknown as CustomEvent).detail?.message}`
     if (!sessionStorage.getItem(key)) {