OverlayScrollbars/packages/overlayscrollbars/tests/jest/support/utils/arrays.test.ts

import { push, each, from, indexOf, runEach, isEmptyArray } from 'support/utils/array';

describe('array utilities', () => {
  describe('push', () => {
    describe('single value', () => {
      test('string', () => {
        const arr: string[] = [];
        const item = 'hi there';

        expect(push(arr, item)).toBe(arr);

        expect(arr).toHaveLength(1);
        expect(arr[0]).toBe(item);
      });

      test('array like', () => {
        const arr: string[] = [];
        const item = ['tuple', 'elem'];

        expect(push(arr, item, true)).toBe(arr);

        expect(arr).toHaveLength(1);
        expect(arr[0]).toBe(item);
      });

      test('array like fake', () => {
        const arr: any[] = [];
        const item = { length: 2 };

        expect(push(arr, item)).toBe(arr);

        expect(arr).toHaveLength(1);
        expect(arr[0]).toBe(item);
      });
    });

    describe('multiple values', () => {
      test('string', () => {
        const arr: string[] = [];
        const items = 'hi there'.split('');

        expect(push(arr, items)).toBe(arr);

        expect(arr).toHaveLength(items.length);
        expect(arr).toEqual(items);
      });

      test('array', () => {
        const arr: string[] = [];
        const items = ['tuple', 'elem'];

        expect(push(arr, items)).toBe(arr);

        expect(arr).toHaveLength(2);
        expect(arr[0]).toBe('tuple');
        expect(arr[1]).toBe('elem');
      });

      test('array like', () => {
        const arr: string[] = [];
        const items = { 0: 'zero', 1: 'one', 2: 'two', length: 3 };

        expect(push(arr, items)).toBe(arr);

        expect(arr).toHaveLength(3);
        expect(arr[0]).toBe('zero');
        expect(arr[1]).toBe('one');
        expect(arr[2]).toBe('two');
      });

      test('array like query selector', () => {
        document.body.innerHTML = '<div><p>testtext<h1></h1></p><div></div></div>';
        const arr: Node[] = [];
        const items = document.querySelectorAll('*');

        expect(push(arr, items)).toBe(arr);

        expect(arr).not.toHaveLength(0);
        arr.forEach((node) => {
          expect(node instanceof window.Element).toBe(true);
        });
      });
    });
  });
  describe('each', () => {
    describe('each through Array', () => {
      test('returns input', () => {
        const arr = [1, 2, 3];
        expect(each(arr, () => {})).toBe(arr);
      });

      test('correct times', () => {
        const arr = [1, 2, 3];
        const eachCallback = jest.fn();

        each(arr, eachCallback);
        expect(eachCallback).toBeCalledTimes(arr.length);
      });

      test('correct callback values', () => {
        const arr = [1, 2, 3];
        each(arr, (value, index, src) => {
          expect(value).toBe(arr[index]);
          expect(arr).toBe(src);
        });
      });

      test('return false equals break', () => {
        const arr = [1, 2, 3];
        const testFunc = jest.fn();

        each(arr, () => {
          testFunc();
          return false;
        });

        expect(testFunc).toBeCalledTimes(1);
      });

      test('return true equals continue', () => {
        const arr = [1, 2, 3];
        const testFunc = jest.fn();

        each(arr, (value, index) => {
          if (index === 0) {
            return true;
          }
          testFunc();
        });

        expect(testFunc).toBeCalledTimes(arr.length - 1);
      });
    });

    describe('each through Object', () => {
      test('returns input', () => {
        const obj = {
          a: 1,
          b: 2,
          c: 3,
        };
        expect(each(obj, () => {})).toBe(obj);
      });

      test('correct times', () => {
        const obj = {
          a: 1,
          b: 2,
          c: 3,
        };
        const eachCallback = jest.fn();

        each(obj, eachCallback);
        expect(eachCallback).toBeCalledTimes(Object.keys(obj).length);
      });

      test('correct callback values', () => {
        const obj = {
          a: 1,
          b: 2,
          c: 3,
        };
        each(obj, (value, key, src) => {
          expect(value).toBe(obj[key]);
          expect(obj).toBe(src);
        });
      });

      test('return false equals break', () => {
        const obj = {
          a: 1,
          b: 2,
          c: 3,
        };
        const testFunc = jest.fn();

        each(obj, () => {
          testFunc();
          return false;
        });

        expect(testFunc).toBeCalledTimes(1);
      });

      test('return true equals continue', () => {
        const obj = {
          a: 1,
          b: 2,
          c: 3,
        };
        const testFunc = jest.fn();
        let index = -1;

        each(obj, () => {
          index++;
          if (index === 0) {
            return true;
          }
          testFunc();
        });

        expect(testFunc).toBeCalledTimes(Object.keys(obj).length - 1);
      });
    });

    describe('each through ArrayLike Object', () => {
      test('returns input', () => {
        const arrLikeObj = document.querySelectorAll('*');
        expect(each(arrLikeObj, () => {})).toBe(arrLikeObj);
      });

      test('correct times', () => {
        const arrLikeObj = document.querySelectorAll('*');
        const eachCallback = jest.fn();

        each(arrLikeObj, eachCallback);
        expect(eachCallback).toBeCalledTimes(arrLikeObj.length);
      });

      test('correct callback values', () => {
        const arrLikeObj = document.querySelectorAll('*');
        each(arrLikeObj, (value, index, src) => {
          expect(value).toBe(arrLikeObj[index]);
          expect(src).toBe(arrLikeObj);
        });
      });

      test('return false equals break', () => {
        const arrLikeObj = document.querySelectorAll('*');
        const testFunc = jest.fn();

        each(arrLikeObj, () => {
          testFunc();
          return false;
        });

        expect(testFunc).toBeCalledTimes(1);
      });

      test('return true equals continue', () => {
        const arrLikeObj = document.querySelectorAll('*');
        const testFunc = jest.fn();

        each(arrLikeObj, (value, index) => {
          if (index === 0) {
            return true;
          }
          testFunc();
        });

        expect(testFunc).toBeCalledTimes(arrLikeObj.length - 1);
      });
    });

    describe('each through nothing', () => {
      test('returns input', () => {
        expect(each(null, () => {})).toBe(null);
        expect(each(undefined, () => {})).toBe(undefined);
      });
    });
  });

  describe('from', () => {
    test('Array.from', () => {
      document.body.innerHTML = '<div></div><div></div><div></div>';
      const fromChildNodes = from(document.body.childNodes);
      expect(fromChildNodes).toEqual(Array.from(document.body.childNodes));
      document.body.innerHTML = '';
    });

    test('fallback', () => {
      document.body.innerHTML = '<div></div><div></div><div></div>';
      const arrFrom = Array.from;
      // @ts-ignore
      Array.from = undefined;
      const fromChildNodes = from(document.body.childNodes);
      Array.from = arrFrom;
      expect(fromChildNodes).toEqual(Array.from(document.body.childNodes));
      document.body.innerHTML = '';
    });

    test('fallback with Set', () => {
      const arrFrom = Array.from;
      // @ts-ignore
      Array.from = undefined;
      const fromResult = from(new Set([1, 2, 3]));
      Array.from = arrFrom;
      expect(fromResult).toEqual([1, 2, 3]);
    });
  });

  describe('runEach', () => {
    test('array', () => {
      const arr = [jest.fn(), null, jest.fn(), undefined, jest.fn()];
      runEach(arr, ['a', 'b', 'c', 'd']);
      arr.forEach((fn) => {
        if (fn) {
          expect(fn).toHaveBeenCalledWith('a', 'b', 'c', 'd');
        }
      });
    });

    test('set', () => {
      const set = new Set([jest.fn(), null, jest.fn(), undefined, jest.fn()]);
      runEach(set, [1, 2, 3, 4]);
      set.forEach((fn) => {
        if (fn) {
          expect(fn).toHaveBeenCalledWith(1, 2, 3, 4);
        }
      });
    });
  });

  test('indexOf', () => {
    const idx = indexOf([1, 2, 3], 2);
    expect(idx).toBe(1);
  });

  test('isEmptyArray', () => {
    expect(isEmptyArray([])).toBe(true);
    expect(isEmptyArray([1, 2, 3])).toBe(false);
    expect(isEmptyArray(null)).toBe(false);
  });
});