Verify canary release
Provide environment information
environment information
sandbox@sse-sandbox-xhvisb:/sandbox$ yarn next info
yarn run v1.22.19
$ /sandbox/node_modules/.bin/next info
Operating System:
Platform: linux
Arch: x64
Version: #58~20.04.1-Ubuntu SMP Tue Jun 14 11:29:12 UTC 2022
Binaries:
Node: 14.19.3
npm: 6.14.17
Yarn: 1.22.19
pnpm: N/A
Relevant packages:
next: 13.0.3-canary.4
eslint-config-next: N/A
react: 18.2.0
react-dom: 18.2.0
warn - Latest canary version not detected, detected: "13.0.3-canary.4", newest: "13.0.3".
Please try the latest canary version (`npm install next@canary`) to confirm the issue still exists before creating a new issue.
Read more - https://nextjs.org/docs/messages/opening-an-issue
Done in 0.84s.
Note: warning at the end seems to be because I'm using next@canary (as instructed) but canary version is older than latest official release. My issue is present in either version.
Describe the Bug
Prop types defined by the parameter on AppType are incorrectly applied to MyApp's props.pageProps instead of MyApp's props.
Expected Behavior
Expected TS types to correctly reflect runtime types.
Link to reproduction
https://codesandbox.io/s/polished-tree-xhvisb?file=/pages/_app.tsx
To Reproduce
- Open the link to reproduction
- Observe code on left (with TS errors) and the produced page on right.
There's a TS error on line 13, complaining Property 'foo' does not exist on type 'AppPropsType<any, MyInitialProps>', even though props.foo does exist at runtime.
Also, there's no TS error on line 14, even though props.pageProps.foo does not exist at runtime.

Verify canary release
Provide environment information
environment information
Note: warning at the end seems to be because I'm using
next@canary(as instructed) butcanaryversion is older than latest official release. My issue is present in either version.Describe the Bug
Prop types defined by the parameter on
AppTypeare incorrectly applied to MyApp'sprops.pagePropsinstead of MyApp'sprops.Expected Behavior
Expected TS types to correctly reflect runtime types.
Link to reproduction
https://codesandbox.io/s/polished-tree-xhvisb?file=/pages/_app.tsx
To Reproduce
There's a TS error on line 13, complaining
Property 'foo' does not exist on type 'AppPropsType<any, MyInitialProps>', even thoughprops.foodoes exist at runtime.Also, there's no TS error on line 14, even though
props.pageProps.foodoes not exist at runtime.