javascript-algorithms-and-data-structures/src/algorithms/string/rabin-karp/__test__/rabinKarp.test.js

Algorithms and data-structures implemented on JavaScript

import { rabinKarp, hashWord, reHashWord } from '../rabinKarp';

describe('rabinKarp', () => {
  it('should correctly calculates hash and re-hash', () => {
    expect(hashWord('a')).toBe(97);
    expect(hashWord('b')).toBe(98);
    expect(hashWord('abc')).toBe(941094);
    expect(hashWord('bcd')).toBe(950601);
    expect(reHashWord(hashWord('abc'), 'abc', 'bcd')).toBe(950601);
    expect(reHashWord(hashWord('abc'), 'abc', 'bcd')).toBe(hashWord('bcd'));
  });

  it('should find substring in a string', () => {
    expect(rabinKarp('abcbcglx', 'abca')).toBe(-1);
    expect(rabinKarp('abcbcglx', 'bcgl')).toBe(3);
    expect(rabinKarp('abcxabcdabxabcdabcdabcy', 'abcdabcy')).toBe(15);
    expect(rabinKarp('abcxabcdabxabcdabcdabcy', 'abcdabca')).toBe(-1);
    expect(rabinKarp('abcxabcdabxaabcdabcabcdabcdabcy', 'abcdabca')).toBe(12);
    expect(rabinKarp('abcxabcdabxaabaabaaaabcdabcdabcy', 'aabaabaaa')).toBe(11);
  });
});