JavaScript/String/test/CheckWordOcurrence.test.js

import { checkWordOccurrence } from '../CheckWordOccurrence'

describe('Testing checkWordOccurrence', () => {
  it('expects throw on insert wrong string', () => {
    const value = 123

    expect(() => checkWordOccurrence(value)).toThrow()
  })

  it('expect throw on insert wrong param for case sensitive', () => {
    const value = 'hello'

    expect(() => checkWordOccurrence(value, value)).toThrow()
  })

  it('check occurrence with case sensitive', () => {
    const stringToTest = 'The quick brown fox jumps over the lazy dog'
    const expectResult = { The: 1, quick: 1, brown: 1, fox: 1, jumps: 1, over: 1, the: 1, lazy: 1, dog: 1 }

    expect(checkWordOccurrence(stringToTest)).toEqual(expectResult)
  })

  it('check occurrence with case insensitive', () => {
    const stringToTest = 'The quick brown fox jumps over the lazy dog'
    const expectResult = { the: 2, quick: 1, brown: 1, fox: 1, jumps: 1, over: 1, lazy: 1, dog: 1 }

    expect(checkWordOccurrence(stringToTest, true)).toEqual(expectResult)
  })
})