QueryClientConfig is missing type args

[aryzing]

Describe the bug

The type QueryClientConfig is missing type args. It is currently defined as

export interface QueryClientConfig {
    queryCache?: QueryCache;
    mutationCache?: MutationCache;
    defaultOptions?: DefaultOptions;
}

and used in the QueryClient constructor as

constructor(config: QueryClientConfig = {}) // ...

This makes it impossible to define a typed config object with types other than unknown.

Your minimal, reproducible example

Already in bug description

Steps to reproduce

In bug description

Expected behavior

Ability to create a typed config with types other than unknown used it's porpertyes type args.

const defaultOptions: DefaultOptions<ApiError> = {/* ... */};
const queryClient = new QueryClient({ defaultOptions });

How often does this bug happen?

Every time

Screenshots or Videos

No response

Platform

N/A

react-query version

"react-query": "3.34.16",

TypeScript version

"typescript": "4.6.2",

Additional context

No response

[aryzing]

Related to this is the fact that when creating a defaultOptions object, there's a type error for the mutationFn prop,

const defaultOptions: DefaultOptions = {};

const queries: QueryObserverOptions = {};
const mutations: MutationObserverOptions = {};


queries.onError = (error) => {/*...*/};
mutations.onError = (error) => {/*...*/};


defaultOptions.queries = queries;
defaultOptions.mutations = mutations;
/* ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  Types of property 'mutationFn' are incompatible.
    Type 'MutationFunction<unknown, void> | undefined' is not assignable to type 'MutationFunction<unknown, unknown> | undefined'.
      Type 'MutationFunction<unknown, void>' is not assignable to type 'MutationFunction<unknown, unknown>'.
        Type 'unknown' is not assignable to type 'void'.

42 defaultOptions.mutations = mutations;
   ~~~~~~~~~~~~~~~~~~~~~~~~
*/

const queryClient = new QueryClient({ defaultOptions });

[Alcas1]

Are they worried that we could potentially use a different error type on some queries? My use case is openapi gen client so we internally guarantee an error type of ApiError. I feel like we should be given the option to define this if we need

[TkDodo]

can someone please provide a reproduction in https://typescriptlang.org/play ? From the description alone, I don't understand the problem fully.

[SevenOutman]

@aryzing Looks like you wish QueryClientConfig/DefaultOptions types to be generic and to take type args because error type is predictable? If I'm understanding you correctly, this discussion has talked about it already.

[aryzing]

The discussion proved useful, will close.