The type definition of the context property of ClientDataFunctionArgs would need to be fixed.

[kazu-2020]

I'm using React Router as a...

framework

Reproduction

The following code declares react-router.config.ts in my project.

declare module "react-router" {
  interface Future {
    unstable_middleware: false;
  }
}

In this case, the type ClientDataFunction must return context: undefined because such behaviour is commented out by packages/react-router/lib/types/route-module.ts. However, it actually returns unstable_RouterContextProvider.

react-router/packages/react-router/lib/types/route-module.ts

Lines 144 to 152 in ff67b74

	/**
	* When `future.unstable_middleware` is not enabled, this is undefined.
	*
	* When `future.unstable_middleware` is enabled, this is an instance of
	* `unstable_RouterContextProvider` and can be used to access context values
	* from your route middlewares. You may pass in initial context values in your
	* `<HydratedRouter unstable_getContext>` prop
	*/
	context: unstable_RouterContextProvider;

System Info

System:
    OS: Linux 6.8 Ubuntu 22.04.5 LTS 22.04.5 LTS (Jammy Jellyfish)
    CPU: (4) x64 Intel(R) N100
    Memory: 9.13 GB / 15.40 GB
    Container: Yes
    Shell: 5.1.16 - /bin/bash
  Binaries:
    Node: 22.11.0 - /usr/local/share/nvm/versions/node/v22.11.0/bin/node
    Yarn: 1.22.22 - /usr/bin/yarn
    npm: 10.9.0 - /usr/local/share/nvm/versions/node/v22.11.0/bin/npm
    pnpm: 10.10.0 - /usr/local/share/nvm/versions/node/v22.11.0/bin/pnpm
  npmPackages:
    @react-router/fs-routes: ^7.5.2 => 7.5.2 
    @react-router/node: ^7.5.2 => 7.5.2 
    @react-router/serve: ^7.5.2 => 7.5.2 
    react-router: ^7.5.2 => 7.5.2 
    vite: ^6.3.3 => 6.3.3

Used Package Manager

npm

Expected Behavior

When I declare unstable_middleware: false in react-router.config.ts, the context property of ClientDataFunctionArgs must return context: undefined.

Actual Behavior

It returns context: unstable_RouterContextProvider.

[kazu-2020]

If the following suggested changes are acceptable, I am willing to create a PR.

react-router/packages/react-router/lib/types/route-module.ts

Lines 144 to 152 in ff67b74

	/**
	* When `future.unstable_middleware` is not enabled, this is undefined.
	*
	* When `future.unstable_middleware` is enabled, this is an instance of
	* `unstable_RouterContextProvider` and can be used to access context values
	* from your route middlewares. You may pass in initial context values in your
	* `<HydratedRouter unstable_getContext>` prop
	*/
	context: unstable_RouterContextProvider;

type ClientDataFunctionArgs<T extends RouteInfo> = {
+    context: MiddlewareEnabled extends true
+    ? unstable_RouterContextProvider
+    : undefined;
-  context: unstable_RouterContextProvider;
}

[brophdawg11]

This actually looks like a typo in the jsdocs.

Client side context was added (rfc) to support middleware but is decoupled from it so that you do not need to be enabling/using middleware to use client-side context: https://github.com/remix-run/react-router/blob/main/CHANGELOG.md#client-side-context-unstable.

Client side - you always get a context value. The conditional types are required for server-side context because it existed before so we need to change it from AppLoadContext -> RouterContextProvider.