@applicaster/zapp-react-native-utils/utils/__tests__/take.test.ts

Applicaster Zapp React Native utilities package

import { take } from "../take";

describe("take", () => {
  it("takes n elements from the beginning", () => {
    expect(take(2, [1, 2, 3])).toEqual([1, 2]);
  });

  it("returns the whole array if n is larger than length", () => {
    expect(take(5, [1, 2, 3])).toEqual([1, 2, 3]);
  });

  it("returns empty array if n is 0", () => {
    expect(take(0, [1, 2, 3])).toEqual([]);
  });

  it("returns empty array for empty input array", () => {
    expect(take(2, [])).toEqual([]);
  });

  it("returns empty array if n is negative", () => {
    expect(take(-1, [1, 2, 3])).toEqual([]);
  });

  it("works with strings in array", () => {
    expect(take(2, ["a", "b", "c"])).toEqual(["a", "b"]);
  });

  it("works with objects in array", () => {
    const arr = [{ id: 1 }, { id: 2 }];
    expect(take(1, arr)).toEqual([{ id: 1 }]);
  });

  it("returns empty array if input is not an array", () => {
    // @ts-expect-error testing non-array input
    expect(take(2, null)).toEqual([]);

    // @ts-expect-error testing non-array input
    expect(take(2, undefined)).toEqual([]);
  });
});