object-entries.ts

export {};

type Entries = readonly Entry[];
type Entry = readonly [PropertyKey, unknown];

type EntryUnionToRecordUnion<T extends Entry> = T extends unknown
  ? Record<T[0], T[1]>
  : never;

// https://stackoverflow.com/questions/50374908/#50375286
type UnionToIntersection<U> = (
  U extends unknown ? (k: U) => void : never
) extends (k: infer I) => void
  ? I
  : never;

declare class Object {
  public static fromEntries<T extends Entries>(
    entries: readonly [...T]
  ): UnionToIntersection<EntryUnionToRecordUnion<T[number]>>;
}

const entries = [
  ["key1", "value1"],
  ["key2", "value2"],
] as const satisfies Entries;

const object = Object.fromEntries(entries);

object.key1; // "value1"
object.key2; // "value2"