NonEmptyObject fails for objects with dynamic properties

[DenizUgur]

The following code is considered as valid by Typescript, although I was expecting it to complain that the filter foo in commonArguments was empty.

import type { NonEmptyObject } from "type-fest"

interface CommonArguments {
  [filter: string]: NonEmptyObject<{ [argument: string]: string | number | undefined }>
}

export const commonArguments: CommonArguments = {
  foo: {}
}

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[sindresorhus]

// @kkmuffme

[kkmuffme]

This issue isn't specific to NonEmptyObject but the same happens also with RequireAtLeastOne:

import type { RequireAtLeastOne } from "type-fest";

type Util = { [argument: string]: string | number | undefined };

interface CommonArguments {
  [filter: string]: RequireAtLeastOne<Util, keyof Util>
  
}

export const commonArguments: CommonArguments = {
  foo: {}
}

The fix for NonEmptyObject is relatively simple:

export type NonEmptyObject<T extends object> = HasRequiredKeys<T> extends true ? T : RequireAtLeastOne<T, keyof T>;

to

export type NonEmptyObject<T extends object> = HasRequiredKeys<OmitIndexSignature<T>> extends true ? T : RequireAtLeastOne<T, keyof T>;

However this issue will persist until someone fixes RequireAtLeastOne