describe('hasVowels()', function() {
    it('should always return a boolean', function() {
        expect('example string'.hasVowels()).toEqual(jasmine.any(Boolean));
    });

    it('should return true if string has vowels', function() {
        expect('oreofe'.hasVowels()).toBe(true);
        expect(('AnDeLa').hasVowels()).toBe(true);
    });

    it('should return false if string has no vowels', function() {
        expect('why'.hasVowels()).toBe(false);
        expect(('twyndyllyngs').hasVowels()).toBe(false);
    });
});

describe('toUpper()', function() {
    it('should always return a string', function() {
        expect('example string'.toUpper()).toEqual(jasmine.any(String));
    });

    it('should return an upper case of the calling string', function() {
        expect('upper case'.toUpper()).toBe('UPPER CASE');
        expect('camelCase'.toUpper()).toBe('CAMELCASE');
        expect('MiXeD cAsE'.toUpper()).toBe('MIXED CASE');
    });
});

describe('toLower()', function() {
    it('should return a string', function() {
        expect('example string'.toLower()).toEqual(jasmine.any(String));
    });
});
describe('hasVowels()', function() {
    it('should always return a boolean', function() {
        expect('example string'.hasVowels()).toEqual(jasmine.any(Boolean));
    });

    it('should return true if string has vowels', function() {
        expect('oreofe'.hasVowels()).toBe(true);
        expect(('AnDeLa').hasVowels()).toBe(true);
    });

    it('should return false if string has no vowels', function() {
        expect('why'.hasVowels()).toBe(false);
        expect(('twyndyllyngs').hasVowels()).toBe(false);
    });
});

describe('toUpper()', function() {
    it('should always return a string', function() {
        expect('example string'.toUpper()).toEqual(jasmine.any(String));
    });

    it('should return an upper case of the calling string', function() {
        expect('upper case'.toUpper()).toBe('UPPER CASE');
        expect('camelCase'.toUpper()).toBe('CAMELCASE');
        expect('MiXeD cAsE'.toUpper()).toBe('MIXED CASE');
    });
});

describe('toLower()', function() {
    it('should return a string', function() {
        expect('example string'.toLower()).toEqual(jasmine.any(String));
    });

    it('shoudl return a lower case of the calling string', function() {
        expect('LOWER CASE'.toLower()).toBe('lower case');
        expect('PascalCaseD'.toLower()).toBe('pascalcased');
        expect('MiXeDcAsE'.toLower()).toBe('mixedcase');
    });
});
Add spec to test the returned result of toLower
Add spec to test the returned result of toLower
