Unmasked type cause the type error in MockedResponse type

[DmitryMasley]

Issue Description

I experience the typescript error in @apollo/client v3.12.5 and v3.12.4 when using MockedProvider or MockedResponse type.

          Type 'Unmasked<sub-TData>' is not assignable to type 'Unmasked<super-TData>'.
            Type 'sub-TData | (sub-TData extends object ? UnwrapFragmentRefs<RemoveMaskedMarker<RemoveFragmentName<sub-TData>>> : sub-TData)' is not assignable to type 'Unmasked<super-TData>'.
              Type 'sub-TData' is not assignable to type 'Unmasked<super-TData>'.
                Type 'super-TData' is not assignable to type 'Unmasked<super-TData>'.

11 export interface MockedResponse<out TData = Record<string, any>, out TVariables = Record<string, any>> {

The origin of the error appears to be here

apollo-client/src/testing/core/mocking/mockLink.ts

Line 40 in cda321c

// @ts-ignore

In the source code it is suppressed but in the installed package there is no ignore statement

export interface MockedResponse<out TData = Record<string, any>, out TVariables = Record<string, any>> {
    request: GraphQLRequest<TVariables>;
    maxUsageCount?: number;
    result?: FetchResult<Unmasked<TData>> | ResultFunction<FetchResult<Unmasked<TData>>, TVariables>;
    error?: Error;
    delay?: number;
    variableMatcher?: VariableMatcher<TVariables>;
    newData?: ResultFunction<FetchResult<Unmasked<TData>>, TVariables>;
}

It seems the error can be fixed if out TData is changed to in out TData. I think it is related to branches in the Unmasked type.

Link to Reproduction

https://codesandbox.io/p/devbox/admiring-newton-94hmcs

Reproduction Steps

• Fork the repo
• npm i && npm run type-check

@apollo/client version

3.12.5

[msakrejda]

I'm still hitting this in 3.13.1. @DmitryMasley, did you find a workaround?

[msakrejda]

If anyone else runs into this, for now, I've downgraded to 3.11.8 which I think is the last version that does not have this issue.

[rjdestigter]

Running into this as well in 3.11.8