import interpolation from '../css-custom-property'; describe('interpolation', () => { it('should return an empty CSS comment when undefined', () => { const actual = interpolation(undefined, undefined, undefined); expect(actual).toEqual('var(--c-, )'); }); it('should return an empty CSS comment when null', () => { const actual = interpolation(null, undefined, undefined); expect(actual).toEqual('var(--c-, )'); }); it('should pass through the value if there are no suffix prefix', () => { const value = 12; const actual = interpolation(value, undefined, undefined); expect(actual).toEqual(value); }); it('should return zero', () => { const value = 0; const actual = interpolation(value, undefined, undefined); expect(actual).toEqual(value); }); it('should append suffix', () => { const actual = interpolation(12, 'px', undefined); expect(actual).toEqual('12px'); }); it('should prepend prefix and append suffix', () => { const actual = interpolation('hello', '"', '"'); expect(actual).toEqual('"hello"'); }); });