should-promised

There some helpers for asserting promises.

.Promise

Assert given object is promise

.fulfilled

Assert given promise will be fulfilled. It will return promise.

it('should be allow to check if promise fulfilled', function() {
  return promised(10).should.be.fulfilled;
});

.fulfilledWith

Assert given promise will be fulfilled with an expected value. It will return promise.

it('should be allow to check if promise fulfilledWith an expected value', function() {
  return promised(10).should.be.fulfilledWith(10);
});

.rejected

Assert given promise will be rejected. It will return promise.

it('should be allow to check if promise rejected', function() {
  return promiseFail().should.be.rejected;
});

.rejectedWith

Assert given promise will be rejected with matched Error. Arguments are the same as Assertion#throw.

.finally or .eventually

This method begin assertions for promises, all next .chain calls will be shortcuts for .thenable calls on promise.

So you can do like this

promised('abc').should.finally.be.exactly('abc')
      .and.be.a.String;
 
//or combine with any of Promise methods as any assertion will return Promise itself
 
Promise.all([
  promised(10).should.finally.be.a.Number,
  promised('abc').should.finally.be.a.String
])

Before .finally

Everything you did before .finally saved into new assertion (but that is not quite usefull as object will be promise). Main idea is to save .not and .any.