alien-node-q-utils

Helper functions for promises with Q on NodeJS. The functions are pure and curried with Ramda.

Install

$ npm install alien-node-q-utils --save

Run the specs

$ npm test

Methods

rejectedPromise

A pre-rejected promise that throws the rejection into an expected catch block.

  it('should pre-reject a promise', function(done) {
    rejectedPromise('foo')
      .catch(function(err) {
        expect(err).toBe('foo');
        done();
      })
  });

resolvedPromise

A pre-resolved promise that passes the resolution into the expected then block.

  it('should pre-resolve a promise', function(done) {
    resolvedPromise('foo')
      .then(function(data) {
        expect(data).toBe('foo');
        done();
      })
  });

rejectOnErrorOrResolve

Given a function signature of fn(deferred, err, data) this will reject deferred if err is provided, otherwise resolve deferred with data.

• Don't forget this function is curried, so the arity must be recognized. (If you omit the data param, you will get a function that accepts only the data param.)

 
  var mockPromiseNoError = function(resolveWith) {
    var deferred = Q.defer();
    rejectOnErrorOrResolve(deferred, undefined, resolveWith);
    return deferred.promise;
  };
  
  var mockPromiseWithError = function(err) {
    var deferred = Q.defer();
    rejectOnErrorOrResolve(deferred, err, undefined);
    return deferred.promise;
  };
 
  it('should resolve if no error is provided', function(done) {
    var deferred = Q.defer();
    mockPromiseNoError('foo')
      .then(function(data) {
        expect(data).toBe('foo');
        done();
      });
  });
  
  it('should reject if error is provided', function(done) {
    var deferred = Q.defer();
    mockPromiseWithError('foo')
      .catch(function(err) {
        expect(err).toBe('foo');
        done();
      });
  });

TODO

• Need specs and descriptions for new mapP methods