import uniqueSlug from './uniqueSlug' describe('uniqueSlug', () => { it('slugifies given string', () => { const string = 'Hello World' const isUnique = jest.fn().mockResolvedValue(true) expect(uniqueSlug(string, isUnique)).resolves.toEqual('hello-world') }) it('increments slugified string until unique', () => { const string = 'Hello World' const isUnique = jest .fn() .mockResolvedValueOnce(false) .mockResolvedValueOnce(true) expect(uniqueSlug(string, isUnique)).resolves.toEqual('hello-world-1') }) it('slugify null string', () => { const string = null const isUnique = jest.fn().mockResolvedValue(true) expect(uniqueSlug(string, isUnique)).resolves.toEqual('anonymous') }) })