Replace required `| undefined` keys with unrequired keys

UndefinedToUnrequired.ts

type Omit<T, K extends keyof T> = Pick<T, Exclude<keyof T, K>>

type OptionalKeys<T> = Exclude<{
  [K in keyof T]: Extract<T[K], undefined> extends never ? never : K;
}[keyof T], undefined>;

type UndefinedToUnrequired<T> = {
  [K in OptionalKeys<T>]?: T[K] 
} & Omit<T, OptionalKeys<T>>

type UndefinedToUnrequired2<T> =
  Partial<Pick<T, OptionalKeys<T>>> & Omit<T, OptionalKeys<T>>

//------------USAGE---------------

type Max = {
  optional: string | undefined;
  optional2?: boolean;
  required: number;
}

type Max2 = UndefinedToUnrequired<Max>;

//have to specify keys
const m1: Max = {
  optional: undefined,
  optional2: undefined,
  required: 123
}

const m2: Max2 = {
  required: 123
}