[fix] type tweaks

[dummdidumm]

• T extends Record<string, any> allows T to be an array, Record<string, known> doesn't, closes Typescript doesn't show an error when trying to return an array in load function #6261
• RequestHandler generic is partial now to align with the other types and prevent type conflicts
• generate definite set of route params, this is more correct and makes hover info better

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[ivanhofer]

@dummdidumm shouldn't this be

export interface RequestHandler<
	Params extends Record<string, string> = Record<string, string>
> {
	(event: RequestEvent<Partial<Params>>): MaybePromise<Response>;
}

?

[dummdidumm]

Why exactly?

[ivanhofer]

I assume you want to makr all params of the event as optional

Here is an example that demonstrates the issue.

[dummdidumm]

I see. No it's working as intended. What you pass for the generic should be applied as-is, i.e. required params should be passed and can be expected to exist. It changes to Partial<..> so that in case you don't type the generic you can't just access the park without checking if it exists (in strict mode)

[ivanhofer]

Ah, now I get it. Thanks for the explanation. Didn't knew this trick before.