issue: Type issue for FieldPathValue in TypeScript v5.0.2

[xsjcTony]

Version Number

7.43.5

Codesandbox/Expo snack

https://stackblitz.com/edit/vitejs-vite-6bugf6?file=src/Example.tsx

Steps to reproduce

1. stop vite dev server
2. run tsc --noEmit in the terminal

Expected behaviour

No issue should be reported, as it's working with TypeScript 4.x

The working solution in v4.x is provided by @bluebill1049 but it's not working in v5.x anymore #9655

A temp workaround could be using PathValue<T, K> instead of FieldPathValue<T, K> straight away instead, but since it's just a type alias, I've no idea why FieldPathValue is not working.

What browsers are you seeing the problem on?

No response

Relevant log output

Argument of type 'FieldPathValue<T, K>' is not assignable to parameter of type 'PathValue<T, K>'.
  Type 'K extends `${infer K}.${infer R}` ? K extends keyof T ? R extends Path<T[K]> ? PathValue<T[K], R> : never : K extends `${number}` ? T extends readonly (infer V)[] ? PathValue<...> : never : never : K extends keyof T ? T[K] : K extends `${number}` ? T extends readonly (infer V)[] ? V : never : never' is not assignable to type 'PathValue<T, K>'.
    Type '(K extends keyof T ? T[K] : K extends `${number}` ? T extends readonly (infer V)[] ? V : never : never) | (string extends keyof T ? string extends Path<...> ? PathValue<...> : never : never)' is not assignable to type 'PathValue<T, K>'.
      Type 'K extends keyof T ? T[K] : K extends `${number}` ? T extends readonly (infer V)[] ? V : never : never' is not assignable to type 'PathValue<T, K>'.
        Type 'T[K] | (K extends `${number}` ? T extends readonly (infer V)[] ? V : never : never)' is not assignable to type 'PathValue<T, K>'.
          Type 'K extends `${number}` ? T extends readonly (infer V)[] ? V : never : never' is not assignable to type 'PathValue<T, K>'.
            Type 'T extends readonly (infer V)[] ? V : never' is not assignable to type 'PathValue<T, K>'.
              Type 'unknown' is not assignable to type 'PathValue<T, K>'.
                Type 'K extends `${infer K}.${infer R}` ? K extends keyof T ? R extends import("C:/dev/gml/node_modules/react-hook-form/dist/types/path/eager").Path<T[K]> ? import("C:/dev/gml/node_modules/react-hook-form/dist/types/path/eager").PathValue<...> : never : K extends `${number}` ? T extends readonly (infer V)[] ? import("C:/d...' is not assignable to type 'K extends `${infer K}.${infer R}` ? K extends keyof T ? R extends import("C:/dev/gml/node_modules/react-hook-form/dist/types/path/eager").Path<T[K]> ? import("C:/dev/gml/node_modules/react-hook-form/dist/types/path/eager").PathValue<...> : never : K extends `${number}` ? T extends readonly (infer V)[] ? import("C:/d...'. Two different types with this name exist, but they are unrelated.
                  Type '(K extends keyof T ? T[K] : K extends `${number}` ? T extends readonly (infer V)[] ? V : never : never) | (string extends keyof T ? string extends Path<...> ? PathValue<...> : never : never)' is not assignable to type 'K extends `${infer K}.${infer R}` ? K extends keyof T ? R extends Path<T[K]> ? PathValue<T[K], R> : never : K extends `${number}` ? T extends readonly (infer V)[] ? PathValue<...> : never : never : K extends keyof T ? T[K] : K extends `${number}` ? T extends readonly (infer V)[] ? V : never : never'.
                    Type 'K extends keyof T ? T[K] : K extends `${number}` ? T extends readonly (infer V)[] ? V : never : never' is not assignable to type 'K extends `${infer K}.${infer R}` ? K extends keyof T ? R extends Path<T[K]> ? PathValue<T[K], R> : never : K extends `${number}` ? T extends readonly (infer V)[] ? PathValue<...> : never : never : K extends keyof T ? T[K] : K extends `${number}` ? T extends readonly (infer V)[] ? V : never : never'.
                      Type 'T[K] | (K extends `${number}` ? T extends readonly (infer V)[] ? V : never : never)' is not assignable to type 'K extends `${infer K}.${infer R}` ? K extends keyof T ? R extends Path<T[K]> ? PathValue<T[K], R> : never : K extends `${number}` ? T extends readonly (infer V)[] ? PathValue<...> : never : never : K extends keyof T ? T[K] : K extends `${number}` ? T extends readonly (infer V)[] ? V : never : never'.
                        Type 'K extends `${number}` ? T extends readonly (infer V)[] ? V : never : never' is not assignable to type 'K extends `${infer K}.${infer R}` ? K extends keyof T ? R extends Path<T[K]> ? PathValue<T[K], R> : never : K extends `${number}` ? T extends readonly (infer V)[] ? PathValue<...> : never : never : K extends keyof T ? T[K] : K extends `${number}` ? T extends readonly (infer V)[] ? V : never : never'.
                          Type 'T extends readonly (infer V)[] ? V : never' is not assignable to type 'K extends `${infer K}.${infer R}` ? K extends keyof T ? R extends Path<T[K]> ? PathValue<T[K], R> : never : K extends `${number}` ? T extends readonly (infer V)[] ? PathValue<...> : never : never : K extends keyof T ? T[K] : K extends `${number}` ? T extends readonly (infer V)[] ? V : never : never'.
                            Type 'unknown' is not assignable to type 'K extends `${infer K}.${infer R}` ? K extends keyof T ? R extends Path<T[K]> ? PathValue<T[K], R> : never : K extends `${number}` ? T extends readonly (infer V)[] ? PathValue<...> : never : never : K extends keyof T ? T[K] : K extends `${number}` ? T extends readonly (infer V)[] ? V : never : never'.
                              Type '`${K}` extends keyof T ? `${R}` extends Path<T[keyof T & `${K}`]> ? PathValue<T[keyof T & `${K}`], Path<T[keyof T & `${K}`]> & `${R}`> : never : `${K}` extends `${number}` ? T extends readonly (infer V)[] ? PathValue<...> : never : never' is not assignable to type 'K extends keyof T ? R extends Path<T[K]> ? PathValue<T[K], R> : never : K extends `${number}` ? T extends readonly (infer V)[] ? PathValue<...> : never : never'.
                                Type '(`${R}` extends Path<T[keyof T & `${K}`]> ? PathValue<T[keyof T & `${K}`], Path<T[keyof T & `${K}`]> & `${R}`> : never) | (`${K}` extends `${number}` ? T extends readonly (infer V)[] ? PathValue<...> : never : never)' is not assignable to type 'K extends keyof T ? R extends Path<T[K]> ? PathValue<T[K], R> : never : K extends `${number}` ? T extends readonly (infer V)[] ? PathValue<...> : never : never'.
                                  Type '`${R}` extends Path<T[keyof T & `${K}`]> ? PathValue<T[keyof T & `${K}`], Path<T[keyof T & `${K}`]> & `${R}`> : never' is not assignable to type 'K extends keyof T ? R extends Path<T[K]> ? PathValue<T[K], R> : never : K extends `${number}` ? T extends readonly (infer V)[] ? PathValue<...> : never : never'.
                                    Type 'PathValue<T[keyof T & `${K}`], Path<T[keyof T & `${K}`]> & `${R}`>' is not assignable to type 'K extends keyof T ? R extends Path<T[K]> ? PathValue<T[K], R> : never : K extends `${number}` ? T extends readonly (infer V)[] ? PathValue<...> : never : never'.
                                      Type 'Path<T[keyof T & `${K}`]> & `${R}` extends `${infer K}.${infer R}` ? K extends keyof T[keyof T & `${K}`] ? R extends Path<T[keyof T & `${K}`][K]> ? PathValue<...> : never : K extends `${number}` ? T[keyof T & `${K}`] extends readonly (infer V)[] ? PathValue<...> : never : never : Path<...> & `${R}` extends keyof T[k...' is not assignable to type 'K extends keyof T ? R extends Path<T[K]> ? PathValue<T[K], R> : never : K extends `${number}` ? T extends readonly (infer V)[] ? PathValue<...> : never : never'.
                                        Type '(Path<T[keyof T & `${K}`]> & `${R}` extends keyof T[keyof T & `${K}`] ? T[keyof T & `${K}`][keyof T[keyof T & `${K}`] & Path<T[keyof T & `${K}`]> & `${R}`] : Path<...> & `${R}` extends `${number}` ? T[keyof T & `${K}`] extends readonly (infer V)[] ? V : never : never) | (string extends keyof T[keyof T & `${K}`] ? st...' is not assignable to type 'K extends keyof T ? R extends Path<T[K]> ? PathValue<T[K], R> : never : K extends `${number}` ? T extends readonly (infer V)[] ? PathValue<...> : never : never'.
                                          Type 'Path<T[keyof T & `${K}`]> & `${R}` extends keyof T[keyof T & `${K}`] ? T[keyof T & `${K}`][keyof T[keyof T & `${K}`] & Path<T[keyof T & `${K}`]> & `${R}`] : Path<...> & `${R}` extends `${number}` ? T[keyof T & `${K}`] extends readonly (infer V)[] ? V : never : never' is not assignable to type 'K extends keyof T ? R extends Path<T[K]> ? PathValue<T[K], R> : never : K extends `${number}` ? T extends readonly (infer V)[] ? PathValue<...> : never : never'.
                                            Type 'T[keyof T & `${K}`][keyof T[keyof T & `${K}`] & Path<T[keyof T & `${K}`]> & `${R}`] | (Path<T[keyof T & `${K}`]> & `${R}` extends `${number}` ? T[keyof T & `${K}`] extends readonly (infer V)[] ? V : never : never)' is not assignable to type 'K extends keyof T ? R extends Path<T[K]> ? PathValue<T[K], R> : never : K extends `${number}` ? T extends readonly (infer V)[] ? PathValue<...> : never : never'.
                                              Type 'Path<T[keyof T & `${K}`]> & `${R}` extends `${number}` ? T[keyof T & `${K}`] extends readonly (infer V)[] ? V : never : never' is not assignable to type 'K extends keyof T ? R extends Path<T[K]> ? PathValue<T[K], R> : never : K extends `${number}` ? T extends readonly (infer V)[] ? PathValue<...> : never : never'.
                                                Type 'T[keyof T & `${K}`] extends readonly (infer V)[] ? V : never' is not assignable to type 'K extends keyof T ? R extends Path<T[K]> ? PathValue<T[K], R> : never : K extends `${number}` ? T extends readonly (infer V)[] ? PathValue<...> : never : never'.
                                                  Type 'unknown' is not assignable to type 'K extends keyof T ? R extends Path<T[K]> ? PathValue<T[K], R> : never : K extends `${number}` ? T extends readonly (infer V)[] ? PathValue<...> : never : never'.

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[bluebill1049]

We haven't upgraded to v5.

[xsjcTony]

Yeah, It's not an urgent thing, but since this is an issue so I'm just reporting it to see if it helps.
I haven't found any other type issues in my project using react-hook-form everywhere, so it should be all good.
And I've totally no idea why it won't work since it's just a type alias.🤣
Please take your time and really appreciate the work.

[bluebill1049]

Thanks, @xsjcTony will get to it #9834 have been really busy with everything at the moment.

[bluebill1049]

could you try with PathValue instead?

[xsjcTony]

PathValue is working as I mentioned that this is a temp work around, but I've no idea why FieldPathValue will break since it's just a simple type alias with generic

[bluebill1049]

Yea, I think that's to do with the latest TS, not much we could do here 😆

[xsjcTony]

@bluebill1049 Yeah, but really want to know what's going on. Can you please share the reason behind this once you get it? Appreciate it.