feature: Implement type guard in the isEnum() function

[kterui9019]

Description

The isEnum() function does not implement type guard.
This is inconvenient when writing code like the following

const somefunction(value: string): USERTYPE => {
  if (!isEnum(value, USERTYPE)) throw new Error("not match enum");
  return value; // Type 'string' is not assignable to type 'USERTYPE'. ts(2322)
}

Proposed solution

A type guard should be implemented in the isEnum() function.
I am now wrapping the isEnum() function in the type guard function myself.

function validateEnumValue<T>(value: any, enumeration: T): value is T[keyof T] {
  return isEnum(value, enumulation);
}

[kterui9019]

Specifically, I believe this can be accomplished by modifying the code as follows.

export function isEnum<T extends Record<string | number, unknown>>(value: unknown, entity: T): value is T[keyof T]  {
  const enumValues = Object.values(entity);
  return enumValues.includes(value);
}

I can send you a pull request if you like.

[braaar]

I'm moving this to the discussion tab, as we are trying to keep the issue count low. Please see this issue for an explanation.