import { countLetters } from '../CountLetters' describe('CountLetters', () => { it('expect throws on use wrong param', () => { expect(() => countLetters(0)).toThrow() }) it('expect throws when using a number in the string', () => { expect(() => countLetters('h3llo')).toThrow() }) it('expect throws when using a special characters in the string', () => { expect(() => countLetters('hello!')).toThrow() }) it('count the letters in a string. Allows lower case', () => { const value = 'hello' const count = countLetters(value) expect(count).toEqual({ h: 1, e: 1, l: 2, o: 1 }) }) it('count the letters in a string. Allows upper case', () => { const value = 'HELLO' const count = countLetters(value) expect(count).toEqual({ h: 1, e: 1, l: 2, o: 1 }) }) it('count the letters in a string. Allows upper and lower case', () => { const value = 'HelLo' const count = countLetters(value) expect(count).toEqual({ h: 1, e: 1, l: 2, o: 1 }) }) })