Similar to Promise.all but executes promises in sequence

javascript-promises-in-sequence.js

/**
 * Executes an array of functions that return a promise in sequence
 * @example
 * promisesInSequence([
 *      function() { return Promise.resolve(1); }
 *      function() { return Promise.resolve(2); },
 *      function() { return Promise.resolve(3); }
 *  ])
 *  .then(function(result) {
 *      console.log(result.join(',')); // output = 1,2,3
 *  });
 * @param {Array<function>} promises - array of functions that return a promise
 * @returns {Promise} executes .then if all resolve otherwise .catch
 */
function promisesInSequence(promises) {
    var result = Promise.resolve();
    var items = [];

    promises.forEach(function (promise) {
        result = result.then(promise).then(function(item) {
            items.push(item);
            return Promise.resolve();
        });
    });

    return result.then(function() {
        return Promise.resolve(items);
    });
}

Example:

promisesInSequence([
     function() { return Promise.resolve(1); }
     function() { return Promise.resolve(2); },
     function() { return Promise.resolve(3); }
])
.then(function(result) {
     console.log(result.join(','));
});

Output 1,2,3