MakeRequired.ts

type FilterOut =
  | string
  | number
  | Date
  | undefined
  | null
  // eslint-disable-next-line @typescript-eslint/ban-types
  | Function
  | FilterOut[];

type FlattenIfArr<T> = T extends (infer R)[] ? R : T;

type FilterKeys<T> = {
  [K in keyof T]: T[K] extends FilterOut ? never : K;
}[keyof T];

export type Depth<T> = Partial<
  { [K in FilterKeys<T>]: Depth<NonNullable<FlattenIfArr<T[K]>>> }
>;

type KeysOf<T> = { [K in keyof T]: K }[keyof T];

type CondNullable<T, U> = T extends null ? U | null : U;

type MakeRequiredRecursive<T, S> = T extends FilterOut ? T : {
  [K in keyof S]-?: K extends keyof T
    ? T[K] extends (infer R)[] | undefined
      ? (Omit<NonNullable<R>, KeysOf<S[K]>> & MakeRequiredRecursive<R, S[K]>)[]
      : CondNullable<
          T[K],
          Omit<NonNullable<T[K]>, KeysOf<S[K]>> &
            MakeRequiredRecursive<NonNullable<T[K]>, S[K]>
        >
    : never;
};

export type MakeRequired<T extends object, U extends Depth<T>> = CondNullable<
  T,
  Omit<T, KeysOf<U>>
> &
  MakeRequiredRecursive<NonNullable<T>, U>;

https://blog.lucas-simon.com/type-safe-database-joins-in-typescript