dist-javascript-algorithms-and-data-structures/dist/data-structures/disjoint-set/__test__/DisjointSetItem.test.js

Algorithms and data-structures implemented on JavaScript

"use strict";

var _DisjointSetItem = _interopRequireDefault(require("../DisjointSetItem"));

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

describe('DisjointSetItem', () => {
  it('should do basic manipulation with disjoint set item', () => {
    const itemA = new _DisjointSetItem.default('A');
    const itemB = new _DisjointSetItem.default('B');
    const itemC = new _DisjointSetItem.default('C');
    const itemD = new _DisjointSetItem.default('D');
    expect(itemA.getRank()).toBe(0);
    expect(itemA.getChildren()).toEqual([]);
    expect(itemA.getKey()).toBe('A');
    expect(itemA.getRoot()).toEqual(itemA);
    expect(itemA.isRoot()).toBe(true);
    expect(itemB.isRoot()).toBe(true);
    itemA.addChild(itemB);
    itemD.setParent(itemC);
    expect(itemA.getRank()).toBe(1);
    expect(itemC.getRank()).toBe(1);
    expect(itemB.getRank()).toBe(0);
    expect(itemD.getRank()).toBe(0);
    expect(itemA.getChildren().length).toBe(1);
    expect(itemC.getChildren().length).toBe(1);
    expect(itemA.getChildren()[0]).toEqual(itemB);
    expect(itemC.getChildren()[0]).toEqual(itemD);
    expect(itemB.getChildren().length).toBe(0);
    expect(itemD.getChildren().length).toBe(0);
    expect(itemA.getRoot()).toEqual(itemA);
    expect(itemB.getRoot()).toEqual(itemA);
    expect(itemC.getRoot()).toEqual(itemC);
    expect(itemD.getRoot()).toEqual(itemC);
    expect(itemA.isRoot()).toBe(true);
    expect(itemB.isRoot()).toBe(false);
    expect(itemC.isRoot()).toBe(true);
    expect(itemD.isRoot()).toBe(false);
    itemA.addChild(itemC);
    expect(itemA.isRoot()).toBe(true);
    expect(itemB.isRoot()).toBe(false);
    expect(itemC.isRoot()).toBe(false);
    expect(itemD.isRoot()).toBe(false);
    expect(itemA.getRank()).toEqual(3);
    expect(itemB.getRank()).toEqual(0);
    expect(itemC.getRank()).toEqual(1);
  });
  it('should do basic manipulation with disjoint set item with custom key extractor', () => {
    const keyExtractor = value => {
      return value.key;
    };

    const itemA = new _DisjointSetItem.default({
      key: 'A',
      value: 1
    }, keyExtractor);
    const itemB = new _DisjointSetItem.default({
      key: 'B',
      value: 2
    }, keyExtractor);
    const itemC = new _DisjointSetItem.default({
      key: 'C',
      value: 3
    }, keyExtractor);
    const itemD = new _DisjointSetItem.default({
      key: 'D',
      value: 4
    }, keyExtractor);
    expect(itemA.getRank()).toBe(0);
    expect(itemA.getChildren()).toEqual([]);
    expect(itemA.getKey()).toBe('A');
    expect(itemA.getRoot()).toEqual(itemA);
    expect(itemA.isRoot()).toBe(true);
    expect(itemB.isRoot()).toBe(true);
    itemA.addChild(itemB);
    itemD.setParent(itemC);
    expect(itemA.getRank()).toBe(1);
    expect(itemC.getRank()).toBe(1);
    expect(itemB.getRank()).toBe(0);
    expect(itemD.getRank()).toBe(0);
    expect(itemA.getChildren().length).toBe(1);
    expect(itemC.getChildren().length).toBe(1);
    expect(itemA.getChildren()[0]).toEqual(itemB);
    expect(itemC.getChildren()[0]).toEqual(itemD);
    expect(itemB.getChildren().length).toBe(0);
    expect(itemD.getChildren().length).toBe(0);
    expect(itemA.getRoot()).toEqual(itemA);
    expect(itemB.getRoot()).toEqual(itemA);
    expect(itemC.getRoot()).toEqual(itemC);
    expect(itemD.getRoot()).toEqual(itemC);
    expect(itemA.isRoot()).toBe(true);
    expect(itemB.isRoot()).toBe(false);
    expect(itemC.isRoot()).toBe(true);
    expect(itemD.isRoot()).toBe(false);
    itemA.addChild(itemC);
    expect(itemA.isRoot()).toBe(true);
    expect(itemB.isRoot()).toBe(false);
    expect(itemC.isRoot()).toBe(false);
    expect(itemD.isRoot()).toBe(false);
    expect(itemA.getRank()).toEqual(3);
    expect(itemB.getRank()).toEqual(0);
    expect(itemC.getRank()).toEqual(1);
  });
});