useFetch default option with ResT generic and transform returning unknown when making external server requests #22164Description
Environment
Node Version: v16.20.0
Nuxt Version: 3.6.2
Reproduction
https://stackblitz.com/edit/nuxt-starter-xrqqhx?file=composables%2Ftest.ts
Describe the bug
When using useFetch with the ResT generic, a TypeScript type error occurs with the default option. The error message is as follows:
useFetch<number[]>('/api/count', {
default: () => [0]
}Type '() => number[]' is not assignable to type '() => Ref<null> | null'.
However, the error can be resolved by using the following syntax:
useFetch<number[]>('/api/count', {
default: (): number[] => [0]
}But when making requests to an external server, using this syntax causes the res parameter in the transform function to be of type unknown instead of number[]. An example of this issue is shown below:
const { data: data2 } = useFetch('https://reqres.in/api/users?page=2', {
default: (): number[] => [],
transform(res){
return res.map(i => i);
}
});'res' is of type 'unknown'.
Additional context
No response
Logs
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