Elsewhere this spec, the promise is tested as 

```
      it('should have a then method', function() {
        expect(typeof promise.then).toBe('function');
      });

      it('should have a catch method', function() {
        expect(typeof promise['catch']).toBe('function');
      });

      it('should have a finally method', function() {
        expect(typeof promise['finally']).toBe('function');
      });
```