microsoft / microsoft/TypeScript

ReturnType is lost after a simple wrapper function

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Description

### 🔎 Search Terms

ReturnType changes to any, wrapper function losing inferred types

### 🕗 Version & Regression Information

- This changed between versions ______ and _______
- This changed in commit or PR _______
- This is the behavior in every version I tried, and I reviewed the FAQ for entries about YES
- I was unable to test this on prior versions because _______

### ⏯ Playground Link

https://codesandbox.io/p/devbox/lingering-fog-5fhtrv

### 💻 Code

```ts
const { useGetPokemonByNameQuery } = pokemonApi;

// Wrapper to demonstrate the issue
export const useGetPokemonByNameQueryWrapper = (
...parameters: Parameters
) => {
return useGetPokemonByNameQuery(...parameters);
};

const useTest = () => {
// data1 has type Pokemon | undefined as expected
const { data: data1 } = useGetPokemonByNameQuery("pikachu");

// data2 has type any???
const { data: data2 } = useGetPokemonByNameQueryWrapper("pikachu");
};
```

### 🙁 Actual behavior

When I wrap any query hook generated by Redux Toolkit Query with any simple wrapper function the return type stops being inferred and changes to 'any'. Check the example in the attached Sandbox in file `/src/services/pokemon.ts`

### 🙂 Expected behavior

I expect the wrapper function to preserve the return type of the wrapped function and to correctly infer it.

### Additional information about the issue

_No response_

Contributor guide

Open the contributing guide

Research direction

Start with the reproduction in the linked CodeSandbox, especially /src/services/pokemon.ts, and compare the inferred types from the direct query hook and its wrapper. Run the example and inspect why data2 becomes any; done means the wrapper preserves the wrapped hook's inferred return type.

Written by the indexing model from the issue text.

Assessment

Tech stack
redux, typescript
Domain
compilers
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
38/100

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