From e392697dd00ff25ab6bec339205e40ef4c902915 Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Sun, 22 Jun 2025 15:31:59 +0900
Subject: [PATCH 01/11] fix: tolerate internal client boundary of server
 package

---
 packages/rsc/src/plugin.ts | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/packages/rsc/src/plugin.ts b/packages/rsc/src/plugin.ts
index e13999152..651817f5a 100644
--- a/packages/rsc/src/plugin.ts
+++ b/packages/rsc/src/plugin.ts
@@ -764,6 +764,25 @@ function vitePluginUseClient(): Plugin[] {
         if (!code.includes("use client")) return;
 
         const ast = await parseAstAsync(code);
+        if (!hasDirective(ast.body, "use client")) return;
+
+        // If `?v=<hash>` reached here, it means client boundary is created
+        // by packages imported on server environment,
+        // which breaks the expectation on dependency optimizer on browser.
+        // https://github.com/hi-ogawa/vite-plugins/pull/384
+        if (id.includes("?v=")) {
+          assert(this.environment.mode === "dev");
+          id = id.replace(/\?v=*/, "?v=");
+          this.warn(
+            `[vite-rsc] detected an internal client boundary created by a package imported on rsc environment`,
+          );
+          // TODO: Does it help something if we copy over the hash from browser environment optimizer?
+          // const hash =
+          //   server.environments.client.depsOptimizer?.metadata.browserHash;
+          // if (hash) {
+          //   id += `?v=${hash}`;
+          // }
+        }
 
         let importId: string;
         let referenceKey: string;

From b8f02768f690f3ec2f1ac16190d4053351df8b9d Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Sun, 22 Jun 2025 15:48:44 +0900
Subject: [PATCH 02/11] test: add test

---
 packages/rsc/examples/basic/e2e/basic.test.ts |  7 ++++++
 packages/rsc/examples/basic/package.json      |  1 +
 .../rsc/examples/basic/src/routes/root.tsx    |  2 ++
 .../basic/test-dep/client-in-server/README.md |  1 +
 .../basic/test-dep/client-in-server/client.js | 22 +++++++++++++++++++
 .../test-dep/client-in-server/package.json    |  9 ++++++++
 .../test-dep/client-in-server/server.d.ts     |  3 +++
 .../basic/test-dep/client-in-server/server.js |  6 +++++
 packages/rsc/src/plugin.ts                    | 18 +++++++--------
 pnpm-lock.yaml                                | 12 ++++++++++
 10 files changed, 72 insertions(+), 9 deletions(-)
 create mode 100644 packages/rsc/examples/basic/test-dep/client-in-server/README.md
 create mode 100644 packages/rsc/examples/basic/test-dep/client-in-server/client.js
 create mode 100644 packages/rsc/examples/basic/test-dep/client-in-server/package.json
 create mode 100644 packages/rsc/examples/basic/test-dep/client-in-server/server.d.ts
 create mode 100644 packages/rsc/examples/basic/test-dep/client-in-server/server.js

diff --git a/packages/rsc/examples/basic/e2e/basic.test.ts b/packages/rsc/examples/basic/e2e/basic.test.ts
index c9e46d5bc..36128d413 100644
--- a/packages/rsc/examples/basic/e2e/basic.test.ts
+++ b/packages/rsc/examples/basic/e2e/basic.test.ts
@@ -620,3 +620,10 @@ test("test serialization @js", async ({ page }) => {
   await page.getByTestId("serialization").click();
   await expect(page.getByTestId("serialization")).toHaveText("ok");
 });
+
+test.only("client in server package", async ({ page }) => {
+  await page.goto("./");
+  await expect(page.getByTestId("client-in-server")).toHaveText(
+    "[test-client-in-server: true]",
+  );
+});
diff --git a/packages/rsc/examples/basic/package.json b/packages/rsc/examples/basic/package.json
index da076ffdb..4c5d1e576 100644
--- a/packages/rsc/examples/basic/package.json
+++ b/packages/rsc/examples/basic/package.json
@@ -23,6 +23,7 @@
     "@types/react": "latest",
     "@types/react-dom": "latest",
     "@vitejs/plugin-react": "latest",
+    "@vitejs/test-dep-client-in-server": "file:./test-dep/client-in-server",
     "tailwindcss": "^4.1.4",
     "vite": "latest",
     "vite-plugin-inspect": "^11.2.0"
diff --git a/packages/rsc/examples/basic/src/routes/root.tsx b/packages/rsc/examples/basic/src/routes/root.tsx
index a5ae38a36..dda439b7a 100644
--- a/packages/rsc/examples/basic/src/routes/root.tsx
+++ b/packages/rsc/examples/basic/src/routes/root.tsx
@@ -19,6 +19,7 @@ import {
 import { TestStyleClient2 } from "./client2";
 import ErrorBoundary from "./error-boundary";
 import "./server.css";
+import TestClientInServerDep from "@vitejs/test-dep-client-in-server";
 import {
   TestServerActionBindAction,
   TestServerActionBindClient,
@@ -81,6 +82,7 @@ export function Root(props: { url: URL }) {
         <TestServerActionBindClient />
         <TestServerActionBindAction />
         <TestSerializationServer />
+        <TestClientInServerDep />
       </body>
     </html>
   );
diff --git a/packages/rsc/examples/basic/test-dep/client-in-server/README.md b/packages/rsc/examples/basic/test-dep/client-in-server/README.md
new file mode 100644
index 000000000..11250c52f
--- /dev/null
+++ b/packages/rsc/examples/basic/test-dep/client-in-server/README.md
@@ -0,0 +1 @@
+test package structure similar to https://github.com/vercel/react-tweet
diff --git a/packages/rsc/examples/basic/test-dep/client-in-server/client.js b/packages/rsc/examples/basic/test-dep/client-in-server/client.js
new file mode 100644
index 000000000..e820ff9bc
--- /dev/null
+++ b/packages/rsc/examples/basic/test-dep/client-in-server/client.js
@@ -0,0 +1,22 @@
+"use client";
+
+import React from "react";
+
+export default function TestClient() {
+  const hydrated = useHydrated();
+  return React.createElement(
+    "span",
+    { "data-testid": "client-in-server" },
+    `[test-client-in-server: ${String(hydrated)}]`,
+  );
+}
+
+const noop = () => {};
+
+function useHydrated() {
+  return React.useSyncExternalStore(
+    noop,
+    () => true,
+    () => false,
+  );
+}
diff --git a/packages/rsc/examples/basic/test-dep/client-in-server/package.json b/packages/rsc/examples/basic/test-dep/client-in-server/package.json
new file mode 100644
index 000000000..e70a8103e
--- /dev/null
+++ b/packages/rsc/examples/basic/test-dep/client-in-server/package.json
@@ -0,0 +1,9 @@
+{
+  "name": "@vitejs/test-dep-client-in-server",
+  "private": true,
+  "type": "module",
+  "exports": "./server.js",
+  "peerDependencies": {
+    "react": "*"
+  }
+}
diff --git a/packages/rsc/examples/basic/test-dep/client-in-server/server.d.ts b/packages/rsc/examples/basic/test-dep/client-in-server/server.d.ts
new file mode 100644
index 000000000..546e51b07
--- /dev/null
+++ b/packages/rsc/examples/basic/test-dep/client-in-server/server.d.ts
@@ -0,0 +1,3 @@
+export default function TestClientInServer(): Promise<
+  import("react").ReactNode
+>;
diff --git a/packages/rsc/examples/basic/test-dep/client-in-server/server.js b/packages/rsc/examples/basic/test-dep/client-in-server/server.js
new file mode 100644
index 000000000..074088e48
--- /dev/null
+++ b/packages/rsc/examples/basic/test-dep/client-in-server/server.js
@@ -0,0 +1,6 @@
+import React from "react";
+import TestClient from "./client.js";
+
+export default async function TestClientInServer() {
+  return React.createElement(TestClient);
+}
diff --git a/packages/rsc/src/plugin.ts b/packages/rsc/src/plugin.ts
index 651817f5a..180fc6eb8 100644
--- a/packages/rsc/src/plugin.ts
+++ b/packages/rsc/src/plugin.ts
@@ -766,22 +766,22 @@ function vitePluginUseClient(): Plugin[] {
         const ast = await parseAstAsync(code);
         if (!hasDirective(ast.body, "use client")) return;
 
-        // If `?v=<hash>` reached here, it means client boundary is created
-        // by packages imported on server environment,
+        // If `?v=<hash>` reached here, it means this is a client boundary created
+        // by a package imported on server environment,
         // which breaks the expectation on dependency optimizer on browser.
         // https://github.com/hi-ogawa/vite-plugins/pull/384
         if (id.includes("?v=")) {
           assert(this.environment.mode === "dev");
-          id = id.replace(/\?v=*/, "?v=");
           this.warn(
             `[vite-rsc] detected an internal client boundary created by a package imported on rsc environment`,
           );
-          // TODO: Does it help something if we copy over the hash from browser environment optimizer?
-          // const hash =
-          //   server.environments.client.depsOptimizer?.metadata.browserHash;
-          // if (hash) {
-          //   id += `?v=${hash}`;
-          // }
+          id = id.split("?v=")[0]!;
+          // Not sure if this helps, but for now, copy over the hash from browser environment optimizer.
+          const hash =
+            server.environments.client.depsOptimizer?.metadata.browserHash;
+          if (hash) {
+            id += `?v=${hash}`;
+          }
         }
 
         let importId: string;
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index ea449ab56..ad4795177 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -584,6 +584,9 @@ importers:
       '@vitejs/plugin-react':
         specifier: ^4.5.0
         version: 4.5.0(vite@6.3.5(@types/node@22.14.1)(jiti@2.4.2)(lightningcss@1.29.2)(terser@5.39.0)(tsx@4.19.3)(yaml@2.7.0))
+      '@vitejs/test-dep-client-in-server':
+        specifier: file:./test-dep/client-in-server
+        version: file:packages/rsc/examples/basic/test-dep/client-in-server(react@19.1.0)
       tailwindcss:
         specifier: ^4.1.4
         version: 4.1.4
@@ -2266,6 +2269,11 @@ packages:
     peerDependencies:
       vite: ^6.3.5
 
+  '@vitejs/test-dep-client-in-server@file:packages/rsc/examples/basic/test-dep/client-in-server':
+    resolution: {directory: packages/rsc/examples/basic/test-dep/client-in-server, type: directory}
+    peerDependencies:
+      react: ^19.1.0
+
   '@vitest/expect@3.2.3':
     resolution: {integrity: sha512-W2RH2TPWVHA1o7UmaFKISPvdicFJH+mjykctJFoAkUw+SPTJTGjUNdKscFBrqM7IPnCVu6zihtKYa7TkZS1dkQ==}
 
@@ -5853,6 +5861,10 @@ snapshots:
     transitivePeerDependencies:
       - supports-color
 
+  '@vitejs/test-dep-client-in-server@file:packages/rsc/examples/basic/test-dep/client-in-server(react@19.1.0)':
+    dependencies:
+      react: 19.1.0
+
   '@vitest/expect@3.2.3':
     dependencies:
       '@types/chai': 5.2.2

From 36cd24b367af56324ccd5825381ea9ce1f2e30f1 Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Sun, 22 Jun 2025 15:53:10 +0900
Subject: [PATCH 03/11] chore: cleanup

---
 packages/rsc/examples/basic/e2e/basic.test.ts | 2 +-
 packages/rsc/src/plugin.ts                    | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/rsc/examples/basic/e2e/basic.test.ts b/packages/rsc/examples/basic/e2e/basic.test.ts
index 36128d413..763205502 100644
--- a/packages/rsc/examples/basic/e2e/basic.test.ts
+++ b/packages/rsc/examples/basic/e2e/basic.test.ts
@@ -621,7 +621,7 @@ test("test serialization @js", async ({ page }) => {
   await expect(page.getByTestId("serialization")).toHaveText("ok");
 });
 
-test.only("client in server package", async ({ page }) => {
+test("client in server package", async ({ page }) => {
   await page.goto("./");
   await expect(page.getByTestId("client-in-server")).toHaveText(
     "[test-client-in-server: true]",
diff --git a/packages/rsc/src/plugin.ts b/packages/rsc/src/plugin.ts
index 180fc6eb8..fa0e29799 100644
--- a/packages/rsc/src/plugin.ts
+++ b/packages/rsc/src/plugin.ts
@@ -776,7 +776,7 @@ function vitePluginUseClient(): Plugin[] {
             `[vite-rsc] detected an internal client boundary created by a package imported on rsc environment`,
           );
           id = id.split("?v=")[0]!;
-          // Not sure if this helps, but for now, copy over the hash from browser environment optimizer.
+          // Not sure if this is good or bad, but for now, copy over the hash from browser environment optimizer.
           const hash =
             server.environments.client.depsOptimizer?.metadata.browserHash;
           if (hash) {

From aed08510558620a0d98c4d504bfe6c314ea80659 Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Sun, 22 Jun 2025 16:27:17 +0900
Subject: [PATCH 04/11] test: tweak

---
 packages/rsc/examples/basic/e2e/basic.test.ts   |  7 +++++--
 .../src/routes/client-in-server/client.tsx      |  6 ++++++
 .../src/routes/client-in-server/server.tsx      | 17 +++++++++++++++++
 packages/rsc/examples/basic/src/routes/root.tsx |  4 ++--
 .../basic/test-dep/client-in-server/README.md   |  1 -
 .../basic/test-dep/client-in-server/client.js   |  6 +-----
 .../test-dep/client-in-server/package.json      |  5 ++++-
 .../basic/test-dep/client-in-server/server.d.ts |  3 ---
 packages/rsc/examples/basic/vite.config.ts      |  4 ++++
 packages/rsc/src/plugin.ts                      |  3 ++-
 10 files changed, 41 insertions(+), 15 deletions(-)
 create mode 100644 packages/rsc/examples/basic/src/routes/client-in-server/client.tsx
 create mode 100644 packages/rsc/examples/basic/src/routes/client-in-server/server.tsx
 delete mode 100644 packages/rsc/examples/basic/test-dep/client-in-server/README.md
 delete mode 100644 packages/rsc/examples/basic/test-dep/client-in-server/server.d.ts

diff --git a/packages/rsc/examples/basic/e2e/basic.test.ts b/packages/rsc/examples/basic/e2e/basic.test.ts
index 763205502..6794832de 100644
--- a/packages/rsc/examples/basic/e2e/basic.test.ts
+++ b/packages/rsc/examples/basic/e2e/basic.test.ts
@@ -621,9 +621,12 @@ test("test serialization @js", async ({ page }) => {
   await expect(page.getByTestId("serialization")).toHaveText("ok");
 });
 
-test("client in server package", async ({ page }) => {
+test("client-in-server package", async ({ page }) => {
   await page.goto("./");
   await expect(page.getByTestId("client-in-server")).toHaveText(
-    "[test-client-in-server: true]",
+    "[test-client-in-server-dep: true]",
+  );
+  await expect(page.getByTestId("client-in-server-client")).toHaveText(
+    "[test-client-in-server-dep-direct-client: true]",
   );
 });
diff --git a/packages/rsc/examples/basic/src/routes/client-in-server/client.tsx b/packages/rsc/examples/basic/src/routes/client-in-server/client.tsx
new file mode 100644
index 000000000..5d1733d85
--- /dev/null
+++ b/packages/rsc/examples/basic/src/routes/client-in-server/client.tsx
@@ -0,0 +1,6 @@
+"use client";
+
+// @ts-ignore
+import TestClientInServerDepClient from "@vitejs/test-dep-client-in-server/client";
+
+export { TestClientInServerDepClient };
diff --git a/packages/rsc/examples/basic/src/routes/client-in-server/server.tsx b/packages/rsc/examples/basic/src/routes/client-in-server/server.tsx
new file mode 100644
index 000000000..39882c0be
--- /dev/null
+++ b/packages/rsc/examples/basic/src/routes/client-in-server/server.tsx
@@ -0,0 +1,17 @@
+// @ts-ignore
+import TestClientInServerDep from "@vitejs/test-dep-client-in-server/server";
+import { TestClientInServerDepClient } from "./client";
+
+export function TestClientInServer() {
+  return (
+    <div>
+      <div data-testid="client-in-server">
+        [test-client-in-server-dep: <TestClientInServerDep />]
+      </div>
+      <div data-testid="client-in-server-client">
+        [test-client-in-server-dep-direct-client:{" "}
+        <TestClientInServerDepClient />]
+      </div>
+    </div>
+  );
+}
diff --git a/packages/rsc/examples/basic/src/routes/root.tsx b/packages/rsc/examples/basic/src/routes/root.tsx
index dda439b7a..fa9287f14 100644
--- a/packages/rsc/examples/basic/src/routes/root.tsx
+++ b/packages/rsc/examples/basic/src/routes/root.tsx
@@ -19,13 +19,13 @@ import {
 import { TestStyleClient2 } from "./client2";
 import ErrorBoundary from "./error-boundary";
 import "./server.css";
-import TestClientInServerDep from "@vitejs/test-dep-client-in-server";
 import {
   TestServerActionBindAction,
   TestServerActionBindClient,
   TestServerActionBindReset,
   TestServerActionBindSimple,
 } from "./action-bind/server";
+import { TestClientInServer } from "./client-in-server/server";
 import { TestSerializationServer } from "./serialization/server";
 import styles from "./server.module.css";
 
@@ -82,7 +82,7 @@ export function Root(props: { url: URL }) {
         <TestServerActionBindClient />
         <TestServerActionBindAction />
         <TestSerializationServer />
-        <TestClientInServerDep />
+        <TestClientInServer />
       </body>
     </html>
   );
diff --git a/packages/rsc/examples/basic/test-dep/client-in-server/README.md b/packages/rsc/examples/basic/test-dep/client-in-server/README.md
deleted file mode 100644
index 11250c52f..000000000
--- a/packages/rsc/examples/basic/test-dep/client-in-server/README.md
+++ /dev/null
@@ -1 +0,0 @@
-test package structure similar to https://github.com/vercel/react-tweet
diff --git a/packages/rsc/examples/basic/test-dep/client-in-server/client.js b/packages/rsc/examples/basic/test-dep/client-in-server/client.js
index e820ff9bc..ef60ddb96 100644
--- a/packages/rsc/examples/basic/test-dep/client-in-server/client.js
+++ b/packages/rsc/examples/basic/test-dep/client-in-server/client.js
@@ -4,11 +4,7 @@ import React from "react";
 
 export default function TestClient() {
   const hydrated = useHydrated();
-  return React.createElement(
-    "span",
-    { "data-testid": "client-in-server" },
-    `[test-client-in-server: ${String(hydrated)}]`,
-  );
+  return React.createElement("span", null, String(hydrated));
 }
 
 const noop = () => {};
diff --git a/packages/rsc/examples/basic/test-dep/client-in-server/package.json b/packages/rsc/examples/basic/test-dep/client-in-server/package.json
index e70a8103e..bd99518f4 100644
--- a/packages/rsc/examples/basic/test-dep/client-in-server/package.json
+++ b/packages/rsc/examples/basic/test-dep/client-in-server/package.json
@@ -2,7 +2,10 @@
   "name": "@vitejs/test-dep-client-in-server",
   "private": true,
   "type": "module",
-  "exports": "./server.js",
+  "exports": {
+    "./server": "./server.js",
+    "./client": "./client.js"
+  },
   "peerDependencies": {
     "react": "*"
   }
diff --git a/packages/rsc/examples/basic/test-dep/client-in-server/server.d.ts b/packages/rsc/examples/basic/test-dep/client-in-server/server.d.ts
deleted file mode 100644
index 546e51b07..000000000
--- a/packages/rsc/examples/basic/test-dep/client-in-server/server.d.ts
+++ /dev/null
@@ -1,3 +0,0 @@
-export default function TestClientInServer(): Promise<
-  import("react").ReactNode
->;
diff --git a/packages/rsc/examples/basic/vite.config.ts b/packages/rsc/examples/basic/vite.config.ts
index c2e6b9c41..58bc83789 100644
--- a/packages/rsc/examples/basic/vite.config.ts
+++ b/packages/rsc/examples/basic/vite.config.ts
@@ -117,4 +117,8 @@ export default { fetch: handler };
   build: {
     minify: false,
   },
+  optimizeDeps: {
+    // even if excluded, the module will be duplicated
+    exclude: ["@vitejs/test-dep-client-in-server/client"],
+  },
 }) as any;
diff --git a/packages/rsc/src/plugin.ts b/packages/rsc/src/plugin.ts
index fa0e29799..8f0dd4c66 100644
--- a/packages/rsc/src/plugin.ts
+++ b/packages/rsc/src/plugin.ts
@@ -776,7 +776,8 @@ function vitePluginUseClient(): Plugin[] {
             `[vite-rsc] detected an internal client boundary created by a package imported on rsc environment`,
           );
           id = id.split("?v=")[0]!;
-          // Not sure if this is good or bad, but for now, copy over the hash from browser environment optimizer.
+          // this doesn't seem entirely sound, but for now,
+          // copy over the hash from browser environment optimizer.
           const hash =
             server.environments.client.depsOptimizer?.metadata.browserHash;
           if (hash) {

From fb3de7934563363c34c4a45e5d4d82f0fa00c592 Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Sun, 22 Jun 2025 16:40:31 +0900
Subject: [PATCH 05/11] fix: avoid stale hash

---
 packages/rsc/examples/basic/vite.config.ts |  3 +--
 packages/rsc/src/plugin.ts                 | 14 +++++++-------
 2 files changed, 8 insertions(+), 9 deletions(-)

diff --git a/packages/rsc/examples/basic/vite.config.ts b/packages/rsc/examples/basic/vite.config.ts
index 58bc83789..35d65a570 100644
--- a/packages/rsc/examples/basic/vite.config.ts
+++ b/packages/rsc/examples/basic/vite.config.ts
@@ -118,7 +118,6 @@ export default { fetch: handler };
     minify: false,
   },
   optimizeDeps: {
-    // even if excluded, the module will be duplicated
-    exclude: ["@vitejs/test-dep-client-in-server/client"],
+    include: ["@vitejs/test-dep-client-in-server/client"],
   },
 }) as any;
diff --git a/packages/rsc/src/plugin.ts b/packages/rsc/src/plugin.ts
index 8f0dd4c66..1d4f1dedd 100644
--- a/packages/rsc/src/plugin.ts
+++ b/packages/rsc/src/plugin.ts
@@ -776,13 +776,13 @@ function vitePluginUseClient(): Plugin[] {
             `[vite-rsc] detected an internal client boundary created by a package imported on rsc environment`,
           );
           id = id.split("?v=")[0]!;
-          // this doesn't seem entirely sound, but for now,
-          // copy over the hash from browser environment optimizer.
-          const hash =
-            server.environments.client.depsOptimizer?.metadata.browserHash;
-          if (hash) {
-            id += `?v=${hash}`;
-          }
+          // Copying over the hash from browser environment optimizer seems sound to avoid double modules,
+          // but this can cause stale hash when browser optimizer reloaded, so for now this is avoided.
+          // const hash =
+          //   server.environments.client.depsOptimizer?.metadata.browserHash;
+          // if (hash) {
+          //   id += `?v=${hash}`;
+          // }
         }
 
         let importId: string;

From a4db8f26280400da877614ceed775b79774de53c Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Sun, 22 Jun 2025 16:52:24 +0900
Subject: [PATCH 06/11] fix: fix client-package-proxy virtual

---
 packages/rsc/src/plugin.ts | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/packages/rsc/src/plugin.ts b/packages/rsc/src/plugin.ts
index 1d4f1dedd..4944ef6a8 100644
--- a/packages/rsc/src/plugin.ts
+++ b/packages/rsc/src/plugin.ts
@@ -766,11 +766,11 @@ function vitePluginUseClient(): Plugin[] {
         const ast = await parseAstAsync(code);
         if (!hasDirective(ast.body, "use client")) return;
 
-        // If `?v=<hash>` reached here, it means this is a client boundary created
-        // by a package imported on server environment,
-        // which breaks the expectation on dependency optimizer on browser.
+        // If non package source `?v=<hash>` reached here, it means this is a client boundary created
+        // by a package imported on server environment, which breaks the expectation on dependency optimizer on browser.
         // https://github.com/hi-ogawa/vite-plugins/pull/384
-        if (id.includes("?v=")) {
+        const packageSource = packageSources.get(id);
+        if (!packageSource && id.includes("?v=")) {
           assert(this.environment.mode === "dev");
           this.warn(
             `[vite-rsc] detected an internal client boundary created by a package imported on rsc environment`,
@@ -787,7 +787,6 @@ function vitePluginUseClient(): Plugin[] {
 
         let importId: string;
         let referenceKey: string;
-        const packageSource = packageSources.get(id);
         if (packageSource) {
           if (this.environment.mode === "dev") {
             importId = `/@id/__x00__virtual:vite-rsc/client-package-proxy/${packageSource}`;

From 29d631e90b5dd197fff1a67a9f2e1b180a337c78 Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Sun, 22 Jun 2025 17:59:16 +0900
Subject: [PATCH 07/11] fix: use client-in-server-package-proxy

---
 packages/rsc/examples/basic/vite.config.ts |  3 +-
 packages/rsc/src/plugin.ts                 | 47 ++++++++++++++--------
 2 files changed, 33 insertions(+), 17 deletions(-)

diff --git a/packages/rsc/examples/basic/vite.config.ts b/packages/rsc/examples/basic/vite.config.ts
index 35d65a570..40bee17c4 100644
--- a/packages/rsc/examples/basic/vite.config.ts
+++ b/packages/rsc/examples/basic/vite.config.ts
@@ -118,6 +118,7 @@ export default { fetch: handler };
     minify: false,
   },
   optimizeDeps: {
-    include: ["@vitejs/test-dep-client-in-server/client"],
+    // TODO: test no double modules
+    exclude: ["@vitejs/test-dep-client-in-server/client"],
   },
 }) as any;
diff --git a/packages/rsc/src/plugin.ts b/packages/rsc/src/plugin.ts
index 4944ef6a8..f67d3682f 100644
--- a/packages/rsc/src/plugin.ts
+++ b/packages/rsc/src/plugin.ts
@@ -766,28 +766,22 @@ function vitePluginUseClient(): Plugin[] {
         const ast = await parseAstAsync(code);
         if (!hasDirective(ast.body, "use client")) return;
 
-        // If non package source `?v=<hash>` reached here, it means this is a client boundary created
-        // by a package imported on server environment, which breaks the expectation on dependency optimizer on browser.
-        // https://github.com/hi-ogawa/vite-plugins/pull/384
+        let importId: string;
+        let referenceKey: string;
         const packageSource = packageSources.get(id);
         if (!packageSource && id.includes("?v=")) {
           assert(this.environment.mode === "dev");
+          // If non package source `?v=<hash>` reached here, this is a client boundary created
+          // by a package imported on server environment, which breaks the expectation on dependency optimizer on browser.
+          // Directory copying over "?v=<hash>" from client optimizer in client reference can make a hashed module stale.
+          // we use another virtual module wrapper to delay such process.
+          // TODO: suggest `optimizeDeps.exclude` and skip warning if that's already the case.
           this.warn(
             `[vite-rsc] detected an internal client boundary created by a package imported on rsc environment`,
           );
-          id = id.split("?v=")[0]!;
-          // Copying over the hash from browser environment optimizer seems sound to avoid double modules,
-          // but this can cause stale hash when browser optimizer reloaded, so for now this is avoided.
-          // const hash =
-          //   server.environments.client.depsOptimizer?.metadata.browserHash;
-          // if (hash) {
-          //   id += `?v=${hash}`;
-          // }
-        }
-
-        let importId: string;
-        let referenceKey: string;
-        if (packageSource) {
+          importId = `/@id/__x00__virtual:vite-rsc/client-in-server-package-proxy/${encodeURIComponent(id.split("?v=")[0]!)}`;
+          referenceKey = importId;
+        } else if (packageSource) {
           if (this.environment.mode === "dev") {
             importId = `/@id/__x00__virtual:vite-rsc/client-package-proxy/${packageSource}`;
             referenceKey = importId;
@@ -858,6 +852,27 @@ function vitePluginUseClient(): Plugin[] {
       code = `export default {${code}};\n`;
       return { code, map: null };
     }),
+    {
+      name: "rsc:virtual-client-in-server-package",
+      async load(id) {
+        if (
+          id.startsWith("\0virtual:vite-rsc/client-in-server-package-proxy/")
+        ) {
+          assert.equal(this.environment.mode, "dev");
+          assert.notEqual(this.environment.name, "rsc");
+          id = decodeURIComponent(
+            id.slice(
+              "\0virtual:vite-rsc/client-in-server-package-proxy/".length,
+            ),
+          );
+          return `
+            export * from ${JSON.stringify(id)};
+            import * as __all__ from ${JSON.stringify(id)};
+            export default __all__.default;
+          `;
+        }
+      },
+    },
     {
       name: "rsc:virtual-client-package",
       resolveId: {

From 767831bd298ca7666d53e2d6f86cd7283bad2dce Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Sun, 22 Jun 2025 18:46:22 +0900
Subject: [PATCH 08/11] test: tewak

---
 packages/rsc/examples/basic/e2e/basic.test.ts  |  4 ++--
 packages/rsc/examples/basic/package.json       |  1 +
 .../src/routes/client-in-server/client.tsx     |  6 ++++--
 .../src/routes/client-in-server/server.tsx     | 15 ++++++++++-----
 .../basic/test-dep/client-in-server/client.js  | 16 +++-------------
 .../test-dep/client-in-server/package.json     |  3 +--
 .../basic/test-dep/client-in-server/server.js  |  4 ++--
 .../basic/test-dep/client-in-server2/client.js | 18 ++++++++++++++++++
 .../test-dep/client-in-server2/package.json    | 12 ++++++++++++
 .../basic/test-dep/client-in-server2/server.js | 10 ++++++++++
 packages/rsc/examples/basic/vite.config.ts     |  6 ++++--
 pnpm-lock.yaml                                 | 12 ++++++++++++
 12 files changed, 79 insertions(+), 28 deletions(-)
 create mode 100644 packages/rsc/examples/basic/test-dep/client-in-server2/client.js
 create mode 100644 packages/rsc/examples/basic/test-dep/client-in-server2/package.json
 create mode 100644 packages/rsc/examples/basic/test-dep/client-in-server2/server.js

diff --git a/packages/rsc/examples/basic/e2e/basic.test.ts b/packages/rsc/examples/basic/e2e/basic.test.ts
index 6794832de..4dcd2c4ec 100644
--- a/packages/rsc/examples/basic/e2e/basic.test.ts
+++ b/packages/rsc/examples/basic/e2e/basic.test.ts
@@ -626,7 +626,7 @@ test("client-in-server package", async ({ page }) => {
   await expect(page.getByTestId("client-in-server")).toHaveText(
     "[test-client-in-server-dep: true]",
   );
-  await expect(page.getByTestId("client-in-server-client")).toHaveText(
-    "[test-client-in-server-dep-direct-client: true]",
+  await expect(page.getByTestId("provider-in-server")).toHaveText(
+    "[test-provider-in-server-dep: true]",
   );
 });
diff --git a/packages/rsc/examples/basic/package.json b/packages/rsc/examples/basic/package.json
index 4c5d1e576..ab847955b 100644
--- a/packages/rsc/examples/basic/package.json
+++ b/packages/rsc/examples/basic/package.json
@@ -24,6 +24,7 @@
     "@types/react-dom": "latest",
     "@vitejs/plugin-react": "latest",
     "@vitejs/test-dep-client-in-server": "file:./test-dep/client-in-server",
+    "@vitejs/test-dep-client-in-server2": "file:./test-dep/client-in-server2",
     "tailwindcss": "^4.1.4",
     "vite": "latest",
     "vite-plugin-inspect": "^11.2.0"
diff --git a/packages/rsc/examples/basic/src/routes/client-in-server/client.tsx b/packages/rsc/examples/basic/src/routes/client-in-server/client.tsx
index 5d1733d85..3acae58bc 100644
--- a/packages/rsc/examples/basic/src/routes/client-in-server/client.tsx
+++ b/packages/rsc/examples/basic/src/routes/client-in-server/client.tsx
@@ -1,6 +1,8 @@
 "use client";
 
 // @ts-ignore
-import TestClientInServerDepClient from "@vitejs/test-dep-client-in-server/client";
+import { TestContextValue } from "@vitejs/test-dep-client-in-server2/client";
 
-export { TestClientInServerDepClient };
+export function TestContextValueIndirect() {
+  return <TestContextValue />;
+}
diff --git a/packages/rsc/examples/basic/src/routes/client-in-server/server.tsx b/packages/rsc/examples/basic/src/routes/client-in-server/server.tsx
index 39882c0be..904ebe7d4 100644
--- a/packages/rsc/examples/basic/src/routes/client-in-server/server.tsx
+++ b/packages/rsc/examples/basic/src/routes/client-in-server/server.tsx
@@ -1,6 +1,8 @@
 // @ts-ignore
-import TestClientInServerDep from "@vitejs/test-dep-client-in-server/server";
-import { TestClientInServerDepClient } from "./client";
+import { TestClientInServerDep } from "@vitejs/test-dep-client-in-server/server";
+// @ts-ignore
+import { TestContextProviderInServer } from "@vitejs/test-dep-client-in-server2/server";
+import { TestContextValueIndirect } from "./client";
 
 export function TestClientInServer() {
   return (
@@ -8,9 +10,12 @@ export function TestClientInServer() {
       <div data-testid="client-in-server">
         [test-client-in-server-dep: <TestClientInServerDep />]
       </div>
-      <div data-testid="client-in-server-client">
-        [test-client-in-server-dep-direct-client:{" "}
-        <TestClientInServerDepClient />]
+      <div data-testid="provider-in-server">
+        [test-provider-in-server-dep:{" "}
+        <TestContextProviderInServer value={true}>
+          <TestContextValueIndirect />
+        </TestContextProviderInServer>
+        ]
       </div>
     </div>
   );
diff --git a/packages/rsc/examples/basic/test-dep/client-in-server/client.js b/packages/rsc/examples/basic/test-dep/client-in-server/client.js
index ef60ddb96..7f60db579 100644
--- a/packages/rsc/examples/basic/test-dep/client-in-server/client.js
+++ b/packages/rsc/examples/basic/test-dep/client-in-server/client.js
@@ -2,17 +2,7 @@
 
 import React from "react";
 
-export default function TestClient() {
-  const hydrated = useHydrated();
-  return React.createElement("span", null, String(hydrated));
-}
-
-const noop = () => {};
-
-function useHydrated() {
-  return React.useSyncExternalStore(
-    noop,
-    () => true,
-    () => false,
-  );
+export function TestClient() {
+  const [ok] = React.useState(() => true)
+  return React.createElement("span", null, String(ok));
 }
diff --git a/packages/rsc/examples/basic/test-dep/client-in-server/package.json b/packages/rsc/examples/basic/test-dep/client-in-server/package.json
index bd99518f4..68ab77952 100644
--- a/packages/rsc/examples/basic/test-dep/client-in-server/package.json
+++ b/packages/rsc/examples/basic/test-dep/client-in-server/package.json
@@ -3,8 +3,7 @@
   "private": true,
   "type": "module",
   "exports": {
-    "./server": "./server.js",
-    "./client": "./client.js"
+    "./server": "./server.js"
   },
   "peerDependencies": {
     "react": "*"
diff --git a/packages/rsc/examples/basic/test-dep/client-in-server/server.js b/packages/rsc/examples/basic/test-dep/client-in-server/server.js
index 074088e48..fda9c7ed1 100644
--- a/packages/rsc/examples/basic/test-dep/client-in-server/server.js
+++ b/packages/rsc/examples/basic/test-dep/client-in-server/server.js
@@ -1,6 +1,6 @@
 import React from "react";
-import TestClient from "./client.js";
+import { TestClient } from "./client.js";
 
-export default async function TestClientInServer() {
+export async function TestClientInServerDep() {
   return React.createElement(TestClient);
 }
diff --git a/packages/rsc/examples/basic/test-dep/client-in-server2/client.js b/packages/rsc/examples/basic/test-dep/client-in-server2/client.js
new file mode 100644
index 000000000..3854302d2
--- /dev/null
+++ b/packages/rsc/examples/basic/test-dep/client-in-server2/client.js
@@ -0,0 +1,18 @@
+"use client";
+
+import React from "react";
+
+const testContext = React.createContext();
+
+export function TestContextProvider(props) {
+  return React.createElement(
+    testContext.Provider,
+    { value: props.value },
+    props.children,
+  );
+}
+
+export function TestContextValue() {
+  const value = React.useContext(testContext);
+  return React.createElement("span", null, String(value));
+}
diff --git a/packages/rsc/examples/basic/test-dep/client-in-server2/package.json b/packages/rsc/examples/basic/test-dep/client-in-server2/package.json
new file mode 100644
index 000000000..fbc55fef5
--- /dev/null
+++ b/packages/rsc/examples/basic/test-dep/client-in-server2/package.json
@@ -0,0 +1,12 @@
+{
+  "name": "@vitejs/test-dep-client-in-server2",
+  "private": true,
+  "type": "module",
+  "exports": {
+    "./server": "./server.js",
+    "./client": "./client.js"
+  },
+  "peerDependencies": {
+    "react": "*"
+  }
+}
diff --git a/packages/rsc/examples/basic/test-dep/client-in-server2/server.js b/packages/rsc/examples/basic/test-dep/client-in-server2/server.js
new file mode 100644
index 000000000..5a0f8727e
--- /dev/null
+++ b/packages/rsc/examples/basic/test-dep/client-in-server2/server.js
@@ -0,0 +1,10 @@
+import React from "react";
+import { TestContextProvider } from "./client.js";
+
+export function TestContextProviderInServer(props) {
+  return React.createElement(
+    TestContextProvider,
+    { value: props.value },
+    props.children,
+  );
+}
diff --git a/packages/rsc/examples/basic/vite.config.ts b/packages/rsc/examples/basic/vite.config.ts
index 40bee17c4..3baf6cc5b 100644
--- a/packages/rsc/examples/basic/vite.config.ts
+++ b/packages/rsc/examples/basic/vite.config.ts
@@ -118,7 +118,9 @@ export default { fetch: handler };
     minify: false,
   },
   optimizeDeps: {
-    // TODO: test no double modules
-    exclude: ["@vitejs/test-dep-client-in-server/client"],
+    exclude: [
+      "@vitejs/test-dep-client-in-server/client",
+      "@vitejs/test-dep-client-in-server2/client",
+    ],
   },
 }) as any;
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index ad4795177..120e25f52 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -587,6 +587,9 @@ importers:
       '@vitejs/test-dep-client-in-server':
         specifier: file:./test-dep/client-in-server
         version: file:packages/rsc/examples/basic/test-dep/client-in-server(react@19.1.0)
+      '@vitejs/test-dep-client-in-server2':
+        specifier: file:./test-dep/client-in-server2
+        version: file:packages/rsc/examples/basic/test-dep/client-in-server2(react@19.1.0)
       tailwindcss:
         specifier: ^4.1.4
         version: 4.1.4
@@ -2269,6 +2272,11 @@ packages:
     peerDependencies:
       vite: ^6.3.5
 
+  '@vitejs/test-dep-client-in-server2@file:packages/rsc/examples/basic/test-dep/client-in-server2':
+    resolution: {directory: packages/rsc/examples/basic/test-dep/client-in-server2, type: directory}
+    peerDependencies:
+      react: ^19.1.0
+
   '@vitejs/test-dep-client-in-server@file:packages/rsc/examples/basic/test-dep/client-in-server':
     resolution: {directory: packages/rsc/examples/basic/test-dep/client-in-server, type: directory}
     peerDependencies:
@@ -5861,6 +5869,10 @@ snapshots:
     transitivePeerDependencies:
       - supports-color
 
+  '@vitejs/test-dep-client-in-server2@file:packages/rsc/examples/basic/test-dep/client-in-server2(react@19.1.0)':
+    dependencies:
+      react: 19.1.0
+
   '@vitejs/test-dep-client-in-server@file:packages/rsc/examples/basic/test-dep/client-in-server(react@19.1.0)':
     dependencies:
       react: 19.1.0

From aff7276157644b0b5a486f1411b84cb08d381157 Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Sun, 22 Jun 2025 18:47:41 +0900
Subject: [PATCH 09/11] chore: lint

---
 packages/rsc/examples/basic/test-dep/client-in-server/client.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/rsc/examples/basic/test-dep/client-in-server/client.js b/packages/rsc/examples/basic/test-dep/client-in-server/client.js
index 7f60db579..959c1cbfd 100644
--- a/packages/rsc/examples/basic/test-dep/client-in-server/client.js
+++ b/packages/rsc/examples/basic/test-dep/client-in-server/client.js
@@ -3,6 +3,6 @@
 import React from "react";
 
 export function TestClient() {
-  const [ok] = React.useState(() => true)
+  const [ok] = React.useState(() => true);
   return React.createElement("span", null, String(ok));
 }

From 148d1882d1700d723d331371165cddeab5692011 Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Sun, 22 Jun 2025 18:50:07 +0900
Subject: [PATCH 10/11] chore: comment

---
 packages/rsc/src/plugin.ts | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/packages/rsc/src/plugin.ts b/packages/rsc/src/plugin.ts
index f67d3682f..3d1c13c44 100644
--- a/packages/rsc/src/plugin.ts
+++ b/packages/rsc/src/plugin.ts
@@ -771,10 +771,11 @@ function vitePluginUseClient(): Plugin[] {
         const packageSource = packageSources.get(id);
         if (!packageSource && id.includes("?v=")) {
           assert(this.environment.mode === "dev");
-          // If non package source `?v=<hash>` reached here, this is a client boundary created
-          // by a package imported on server environment, which breaks the expectation on dependency optimizer on browser.
-          // Directory copying over "?v=<hash>" from client optimizer in client reference can make a hashed module stale.
-          // we use another virtual module wrapper to delay such process.
+          // If non package source `?v=<hash>` reached here, this is a client boundary
+          // created by a package imported on server environment, which breaks the
+          // expectation on dependency optimizer on browser. Directly copying over
+          // "?v=<hash>" from client optimizer in client reference can make a hashed
+          // module stale, so we use another virtual module wrapper to delay such process.
           // TODO: suggest `optimizeDeps.exclude` and skip warning if that's already the case.
           this.warn(
             `[vite-rsc] detected an internal client boundary created by a package imported on rsc environment`,

From ad7212e03c32db4b1a645d030921135469d7fa22 Mon Sep 17 00:00:00 2001
From: Hiroshi Ogawa <hi.ogawa.zz@gmail.com>
Date: Sun, 22 Jun 2025 18:53:01 +0900
Subject: [PATCH 11/11] chore: comment

---
 packages/rsc/src/plugin.ts | 1 +
 1 file changed, 1 insertion(+)

diff --git a/packages/rsc/src/plugin.ts b/packages/rsc/src/plugin.ts
index 3d1c13c44..2cb2299f8 100644
--- a/packages/rsc/src/plugin.ts
+++ b/packages/rsc/src/plugin.ts
@@ -866,6 +866,7 @@ function vitePluginUseClient(): Plugin[] {
               "\0virtual:vite-rsc/client-in-server-package-proxy/".length,
             ),
           );
+          // TODO: avoid `export default undefined`
           return `
             export * from ${JSON.stringify(id)};
             import * as __all__ from ${JSON.stringify(id)};