testing failed promises with mocha's built-in promise support [duplicate]

Answer 1

You can return a promise to signal that the test is asynchronous:

function something() {
  return Q.reject(Error('fail'));
}

it('should reject', function() {
  return something().then(function() {
    throw new Error('expected rejection');
  },
  function() {
    return 'passed :]';
  });
});