typescriptでArrayを指定数毎に区切る

こういう感じで、配列を指定数毎に区切りたい

describe("chunk test", () => {
  it("number", () => {
    expect(chunk([1, 2, 3, 4, 5, 6, 7, 8, 9, 10], 3)).toStrictEqual([
      [1, 2, 3],
      [4, 5, 6],
      [7, 8, 9],
      [10],
    ]);
  });
  it("string", () => {
    expect(chunk(["one", "two", "three", "four"], 2)).toStrictEqual([
      ["one", "two"],
      ["three", "four"],
    ]);
  });
});

これで出来ました

export function chunk<T>(arr: Array<T>, size: number): Array<Array<T>> {
  return arr.reduce(
    (newarr: Array<Array<T>>, _: T, i: number) =>
      i % size ? newarr : [...newarr, arr.slice(i, i + size)],
    [] as Array<Array<T>>
  );
}