fix(react-router): allow JSX to be passed full circle with temporary reference sets

docs/start/rsc/route-module.md

@@ -47,7 +47,7 @@ export default function MyRouteComponent() {
 }
 ```
 
-You can also export it as `Component` if that's your think.
+You can also export it as `Component` if that's your thing.
 
 ### Props passed to the Component
 

integration/helpers/rsc-parcel-framework/package.json

@@ -28,7 +28,7 @@
     "@types/react-dom": "^19.0.3",
     "@types/react": "^19.0.8",
     "parcel": "2.15.0",
-    "parcel-config-react-router-experimental": "1.0.24",
+    "parcel-config-react-router-experimental": "1.0.25",
     "typescript": "^5.1.6"
   },
   "dependencies": {

integration/helpers/rsc-parcel/src/browser.tsx

@@ -10,6 +10,7 @@ import {
 } from "react-router";
 import {
   createFromReadableStream,
+  createTemporaryReferenceSet,
   encodeReply,
   setServerCallback,
   // @ts-expect-error - no types for this yet
@@ -19,6 +20,7 @@ import {
 setServerCallback(
   createCallServer({
     createFromReadableStream,
+    createTemporaryReferenceSet,
     encodeReply,
   })
 );

integration/helpers/rsc-parcel/src/server.tsx

@@ -2,6 +2,7 @@ import { createRequestListener } from "@mjackson/node-fetch-server";
 import express from "express";
 import { unstable_matchRSCServerRequest as matchRSCServerRequest } from "react-router";
 import {
+  createTemporaryReferenceSet,
   decodeAction,
   decodeFormState,
   decodeReply,
@@ -18,6 +19,7 @@ import { assets } from "./parcel-entry-wrapper"
 function fetchServer(request: Request) {
   return matchRSCServerRequest({
     // Provide the React Server touchpoints.
+    createTemporaryReferenceSet,
     decodeReply,
     decodeAction,
     decodeFormState,
@@ -27,8 +29,8 @@ function fetchServer(request: Request) {
     // The app routes.
     routes,
     // Encode the match with the React Server implementation.
-    generateResponse(match) {
-      return new Response(renderToReadableStream(match.payload), {
+    generateResponse(match, options) {
+      return new Response(renderToReadableStream(match.payload, options), {
         status: match.statusCode,
         headers: match.headers,
       });

integration/helpers/rsc-vite/src/entry.browser.tsx

@@ -2,6 +2,7 @@ import { startTransition, StrictMode } from "react";
 import { hydrateRoot } from "react-dom/client";
 import {
   createFromReadableStream,
+  createTemporaryReferenceSet,
   encodeReply,
   setServerCallback,
 } from "@hiogawa/vite-rsc/browser";
@@ -15,6 +16,7 @@ import type { unstable_RSCPayload as RSCPayload } from "react-router";
 setServerCallback(
   createCallServer({
     createFromReadableStream,
+    createTemporaryReferenceSet,
     encodeReply,
   })
 );

integration/helpers/rsc-vite/src/entry.rsc.tsx

@@ -1,4 +1,5 @@
 import {
+  createTemporaryReferenceSet,
   decodeAction,
   decodeReply,
   loadServerAction,
@@ -10,13 +11,14 @@ import { routes } from "./routes";
 
 export async function fetchServer(request: Request) {
   return await matchRSCServerRequest({
+    createTemporaryReferenceSet,
     decodeReply,
     decodeAction,
     loadServerAction,
     request,
     routes,
-    generateResponse(match) {
-      return new Response(renderToReadableStream(match.payload), {
+    generateResponse(match, options) {
+      return new Response(renderToReadableStream(match.payload, options), {
         status: match.statusCode,
         headers: match.headers,
       });

integration/rsc/rsc-test.ts

@@ -869,6 +869,74 @@ implementations.forEach((implementation) => {
         // Ensure this is using RSC
         validateRSCHtml(await page.content());
       });
+
+      test("Supports React Server Function References", async ({ page }) => {
+        let port = await getPort();
+        stop = await setupRscTest({
+          implementation,
+          port,
+          files: {
+            "src/routes/home.actions.ts": js`
+              "use server";
+
+              export async function incrementCounter({count, ref}: {count: number; ref: unknown}, formData: FormData) {
+                return {count: count + parseInt(formData.get("by") as string || "1", 10), ref};
+              }
+            `,
+            "src/routes/home.tsx": js`
+              export { default } from "./home.client";
+            `,
+            "src/routes/home.client.tsx": js`
+              "use client";
+
+              import { useActionState } from "react";
+
+              import { incrementCounter } from "./home.actions";
+
+              const ogRef = {};
+              export default function HomeRoute() {
+                const [{count,ref}, incrementCounterAction, incrementing] = useActionState(incrementCounter, {count: 0, ref: ogRef});
+
+                return (
+                  <div>
+                    <h2 data-home>Home: ({count})</h2>
+                    <h2 data-home-ref>{ref === ogRef ? "good" : "bad"}</h2>
+                    <form action={incrementCounterAction}>
+                      <button type="submit" data-submit>
+                        {incrementing ? "Updating via Server Function" : "Update via Server Function"}
+                      </button>
+                    </form>
+                  </div>
+                );
+              }
+            `,
+          },
+        });
+
+        await page.goto(`http://localhost:${port}/`);
+
+        // Verify initial server render
+        await page.waitForSelector("[data-home]");
+        expect(await page.locator("[data-home]").textContent()).toBe(
+          "Home: (0)"
+        );
+        await expect(page.locator("[data-home-ref]")).toHaveText("good");
+
+        // Submit the form to trigger server function
+        await page.click("[data-submit]");
+
+        // Verify server function updated the UI
+        await expect(page.locator("[data-home]")).toHaveText("Home: (1)");
+        await expect(page.locator("[data-home-ref]")).toHaveText("good");
+
+        // Submit again to ensure server functions work repeatedly
+        await page.click("[data-submit]");
+        await expect(page.locator("[data-home]")).toHaveText("Home: (2)");
+        await expect(page.locator("[data-home-ref]")).toHaveText("good");
+
+        // Ensure this is using RSC
+        validateRSCHtml(await page.content());
+      });
     });
 
     test.describe("Errors", () => {

packages/react-router/index-react-server.ts

@@ -2,7 +2,6 @@
 export { matchRSCServerRequest as unstable_matchRSCServerRequest } from "./lib/rsc/server.rsc";
 
 export type {
-  CreateFromReadableStreamFunction as unstable_CreateFromReadableStreamFunction,
   DecodeActionFunction as unstable_DecodeActionFunction,
   DecodeFormStateFunction as unstable_DecodeFormStateFunction,
   DecodeReplyFunction as unstable_DecodeReplyFunction,

packages/react-router/index.ts

@@ -283,11 +283,15 @@ export type { Register } from "./lib/types/register";
 export { href } from "./lib/href";
 
 // RSC
-export type { EncodeReplyFunction as unstable_EncodeReplyFunction } from "./lib/rsc/browser";
+export type {
+  BrowserCreateFromReadableStreamFunction as unstable_BrowserCreateFromReadableStreamFunction,
+  EncodeReplyFunction as unstable_EncodeReplyFunction,
+} from "./lib/rsc/browser";
 export {
   createCallServer as unstable_createCallServer,
   RSCHydratedRouter as unstable_RSCHydratedRouter,
 } from "./lib/rsc/browser";
+export type { SSRCreateFromReadableStreamFunction as unstable_SSRCreateFromReadableStreamFunction } from "./lib/rsc/server.ssr";
 export {
   routeRSCServerRequest as unstable_routeRSCServerRequest,
   RSCStaticRouter as unstable_RSCStaticRouter,
@@ -300,7 +304,6 @@ import type { matchRSCServerRequest } from "./lib/rsc/server.rsc";
 export declare const unstable_matchRSCServerRequest: typeof matchRSCServerRequest;
 
 export type {
-  CreateFromReadableStreamFunction as unstable_CreateFromReadableStreamFunction,
   DecodeActionFunction as unstable_DecodeActionFunction,
   DecodeFormStateFunction as unstable_DecodeFormStateFunction,
   DecodeReplyFunction as unstable_DecodeReplyFunction,

packages/react-router/lib/rsc/browser.tsx

@@ -16,7 +16,6 @@ import type {
   RSCPayload,
   RSCRouteManifest,
   RSCRenderPayload,
-  CreateFromReadableStreamFunction,
 } from "./server.rsc";
 import type {
   DataStrategyFunction,
@@ -41,7 +40,19 @@ import {
 } from "../dom/ssr/routes";
 import { RSCRouterGlobalErrorBoundary } from "./errorBoundaries";
 
-export type EncodeReplyFunction = (args: unknown[]) => Promise<BodyInit>;
+export type BrowserCreateFromReadableStreamFunction = (
+  body: ReadableStream<Uint8Array>,
+  {
+    temporaryReferences,
+  }: {
+    temporaryReferences: unknown;
+  }
+) => Promise<unknown>;
+
+export type EncodeReplyFunction = (
+  args: unknown[],
+  options: { temporaryReferences: unknown }
+) => Promise<BodyInit>;
 
 declare global {
   interface Window {
@@ -53,10 +64,12 @@ declare global {
 
 export function createCallServer({
   createFromReadableStream,
+  createTemporaryReferenceSet,
   encodeReply,
   fetch: fetchImplementation = fetch,
 }: {
-  createFromReadableStream: CreateFromReadableStreamFunction;
+  createFromReadableStream: BrowserCreateFromReadableStreamFunction;
+  createTemporaryReferenceSet: () => unknown;
   encodeReply: EncodeReplyFunction;
   fetch?: (request: Request) => Promise<Response>;
 }) {
@@ -65,9 +78,10 @@ export function createCallServer({
     let actionId = (window.__routerActionID =
       (window.__routerActionID ??= 0) + 1);
 
+    const temporaryReferences = createTemporaryReferenceSet();
     const response = await fetchImplementation(
       new Request(location.href, {
-        body: await encodeReply(args),
+        body: await encodeReply(args, { temporaryReferences }),
         method: "POST",
         headers: {
           Accept: "text/x-component",
@@ -78,9 +92,9 @@ export function createCallServer({
     if (!response.body) {
       throw new Error("No response body");
     }
-    const payload = (await createFromReadableStream(
-      response.body
-    )) as RSCPayload;
+    const payload = (await createFromReadableStream(response.body, {
+      temporaryReferences,
+    })) as RSCPayload;
 
     if (payload.type === "redirect") {
       if (payload.reload) {
@@ -159,7 +173,7 @@ function createRouterFromPayload({
   payload,
 }: {
   payload: RSCPayload;
-  createFromReadableStream: CreateFromReadableStreamFunction;
+  createFromReadableStream: BrowserCreateFromReadableStreamFunction;
   fetchImplementation: (request: Request) => Promise<Response>;
 }) {
   if (window.__router) return window.__router;
@@ -261,7 +275,7 @@ export function getRSCSingleFetchDataStrategy(
   getRouter: () => DataRouter,
   ssr: boolean,
   basename: string | undefined,
-  createFromReadableStream: CreateFromReadableStreamFunction,
+  createFromReadableStream: BrowserCreateFromReadableStreamFunction,
   fetchImplementation: (request: Request) => Promise<Response>
 ): DataStrategyFunction {
   // TODO: Clean this up with a shared type
@@ -345,7 +359,7 @@ export function getRSCSingleFetchDataStrategy(
 }
 
 function getFetchAndDecodeViaRSC(
-  createFromReadableStream: CreateFromReadableStreamFunction,
+  createFromReadableStream: BrowserCreateFromReadableStreamFunction,
   fetchImplementation: (request: Request) => Promise<Response>
 ): FetchAndDecodeFunction {
   return async (
@@ -375,7 +389,9 @@ function getFetchAndDecodeViaRSC(
     invariant(res.body, "No response body to decode");
 
     try {
-      const payload = (await createFromReadableStream(res.body)) as RSCPayload;
+      const payload = (await createFromReadableStream(res.body, {
+        temporaryReferences: undefined,
+      })) as RSCPayload;
       if (payload.type === "redirect") {
         return {
           status: res.status,
@@ -434,7 +450,7 @@ export function RSCHydratedRouter({
   payload,
   routeDiscovery = "eager",
 }: {
-  createFromReadableStream: CreateFromReadableStreamFunction;
+  createFromReadableStream: BrowserCreateFromReadableStreamFunction;
   fetch?: (request: Request) => Promise<Response>;
   payload: RSCPayload;
   routeDiscovery?: "eager" | "lazy";
@@ -733,7 +749,7 @@ function getManifestUrl(paths: string[]): URL | null {
 
 async function fetchAndApplyManifestPatches(
   paths: string[],
-  createFromReadableStream: CreateFromReadableStreamFunction,
+  createFromReadableStream: BrowserCreateFromReadableStreamFunction,
   fetchImplementation: (request: Request) => Promise<Response>,
   signal?: AbortSignal
 ) {
@@ -755,7 +771,9 @@ async function fetchAndApplyManifestPatches(
     throw new Error("Unable to fetch new route matches from the server");
   }
 
-  let payload = (await createFromReadableStream(response.body)) as RSCPayload;
+  let payload = (await createFromReadableStream(response.body, {
+    temporaryReferences: undefined,
+  })) as RSCPayload;
   if (payload.type !== "manifest") {
     throw new Error("Failed to patch routes");
   }