Promessa

A Node.js Promises library which complies with the Promises/A+ specification. Written with a focus towards readability over high performance and used as a learning exercise to better understand how Promises function and evaluate themselves internally.

• Usage
• Methods
• Tests
• Reference

Usage

let Promessa = require('promessa');

let myPromise = new Promessa((resolve,reject) => {

	// implement here
});

Methods

Promessa implements the following constructor and prototype:

• new Promessa(function(resolve,reject) { ... })
• Promessa.prototype.then(onFulfilled,onRejected)
• Promise.prototype.catch(onRejected)

In addition, the following utility methods are available:

• Promessa.resolve(value)
• Promessa.reject(reason)
• Promessa.all(promiseList) (with promiseList as an Array)
• Promessa.race(promiseList) (with promiseList as an Array)

For use of these methods, I won't repeat what is already available via the excellent MDN Promise documentation.

Tests

Library passes the promises-aplus-tests suite to meet the Promises/A+ specification. In addition a basic test suite for Promessa.all(promiseList) and Promessa.race(promiseList) methods is included.

All tests are run via test/run.sh.

Reference

Promise implementations/documentation referred to during development:

• https://github.com/then/promise
• https://github.com/abdulapopoola/Adehun
• https://www.promisejs.org/patterns/