From a037c0867ddbc18a5e5911cbf5b749e7c850713b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bal=C3=A1zs=20Orb=C3=A1n?= <info@balazsorban.com>
Date: Fri, 26 Aug 2022 02:10:11 +0100
Subject: [PATCH] fix(ts): use `AppProps`'s generic for `pageProps` (#38867)

Currently, you cannot set `pageProps`'s type when using `AppProps`'s generic, it's always `any`.

Before:
![image](https://user-images.githubusercontent.com/18369201/180234440-3b37460c-ff92-413f-9d1c-38e35e35a5b4.png)


After:
![image](https://user-images.githubusercontent.com/18369201/180234644-335eec85-0315-4ff8-aba1-53edf0b64e1a.png)



## Bug

- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have helpful link attached, see `contributing.md`

## Feature

- [ ] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have helpful link attached, see `contributing.md`

## Documentation / Examples

- [ ] Make sure the linting passes by running `pnpm lint`
- [ ] The examples guidelines are followed from [our contributing doc](https://github.com/vercel/next.js/blob/canary/contributing.md#adding-examples)
---
 packages/next/shared/lib/utils.ts        | 8 ++++----
 test/integration/app-tree/pages/_app.tsx | 5 +----
 2 files changed, 5 insertions(+), 8 deletions(-)

diff --git a/packages/next/shared/lib/utils.ts b/packages/next/shared/lib/utils.ts
index 6ec6a7dcc0d56..1e6bb46df7bc0 100644
--- a/packages/next/shared/lib/utils.ts
+++ b/packages/next/shared/lib/utils.ts
@@ -165,15 +165,15 @@ export type AppContextType<R extends NextRouter = NextRouter> = {
   router: R
 }
 
-export type AppInitialProps = {
-  pageProps: any
+export type AppInitialProps<P = any> = {
+  pageProps: P
 }
 
 export type AppPropsType<
   R extends NextRouter = NextRouter,
   P = {}
-> = AppInitialProps & {
-  Component: NextComponentType<NextPageContext, any, P>
+> = AppInitialProps<P> & {
+  Component: NextComponentType<NextPageContext, any, any>
   router: R
   __N_SSG?: boolean
   __N_SSP?: boolean
diff --git a/test/integration/app-tree/pages/_app.tsx b/test/integration/app-tree/pages/_app.tsx
index 78e095ae1a6ca..bcd7a5546e8ab 100644
--- a/test/integration/app-tree/pages/_app.tsx
+++ b/test/integration/app-tree/pages/_app.tsx
@@ -7,7 +7,7 @@ import { renderToString } from 'react-dom/server'
 
 export const DummyContext = createContext(null)
 
-class MyApp<P = {}> extends App<P & { html: string }> {
+export default class MyApp extends App<{ html: string }> {
   static async getInitialProps({ Component, AppTree, ctx }: AppContext) {
     let pageProps = {}
 
@@ -34,7 +34,6 @@ class MyApp<P = {}> extends App<P & { html: string }> {
   render() {
     const { Component, pageProps, html, router } = this.props
     const href = router.pathname === '/' ? '/another' : '/'
-
     const child =
       html && router.pathname !== '/hello' ? (
         <>
@@ -52,5 +51,3 @@ class MyApp<P = {}> extends App<P & { html: string }> {
     )
   }
 }
-
-export default MyApp