added unit testing, and started implementing unit tests...phew

node_modules/async/each.js

@@ -0,0 +1,82 @@
+'use strict';
+
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+exports.default = eachLimit;
+
+var _eachOf = require('./eachOf');
+
+var _eachOf2 = _interopRequireDefault(_eachOf);
+
+var _withoutIndex = require('./internal/withoutIndex');
+
+var _withoutIndex2 = _interopRequireDefault(_withoutIndex);
+
+var _wrapAsync = require('./internal/wrapAsync');
+
+var _wrapAsync2 = _interopRequireDefault(_wrapAsync);
+
+function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
+
+/**
+ * Applies the function `iteratee` to each item in `coll`, in parallel.
+ * The `iteratee` is called with an item from the list, and a callback for when
+ * it has finished. If the `iteratee` passes an error to its `callback`, the
+ * main `callback` (for the `each` function) is immediately called with the
+ * error.
+ *
+ * Note, that since this function applies `iteratee` to each item in parallel,
+ * there is no guarantee that the iteratee functions will complete in order.
+ *
+ * @name each
+ * @static
+ * @memberOf module:Collections
+ * @method
+ * @alias forEach
+ * @category Collection
+ * @param {Array|Iterable|Object} coll - A collection to iterate over.
+ * @param {AsyncFunction} iteratee - An async function to apply to
+ * each item in `coll`. Invoked with (item, callback).
+ * The array index is not passed to the iteratee.
+ * If you need the index, use `eachOf`.
+ * @param {Function} [callback] - A callback which is called when all
+ * `iteratee` functions have finished, or an error occurs. Invoked with (err).
+ * @example
+ *
+ * // assuming openFiles is an array of file names and saveFile is a function
+ * // to save the modified contents of that file:
+ *
+ * async.each(openFiles, saveFile, function(err){
+ *   // if any of the saves produced an error, err would equal that error
+ * });
+ *
+ * // assuming openFiles is an array of file names
+ * async.each(openFiles, function(file, callback) {
+ *
+ *     // Perform operation on file here.
+ *     console.log('Processing file ' + file);
+ *
+ *     if( file.length > 32 ) {
+ *       console.log('This file name is too long');
+ *       callback('File name too long');
+ *     } else {
+ *       // Do work to process file here
+ *       console.log('File processed');
+ *       callback();
+ *     }
+ * }, function(err) {
+ *     // if any of the file processing produced an error, err would equal that error
+ *     if( err ) {
+ *       // One of the iterations produced an error.
+ *       // All processing will now stop.
+ *       console.log('A file failed to process');
+ *     } else {
+ *       console.log('All files have been processed successfully');
+ *     }
+ * });
+ */
+function eachLimit(coll, iteratee, callback) {
+  (0, _eachOf2.default)(coll, (0, _withoutIndex2.default)((0, _wrapAsync2.default)(iteratee)), callback);
+}
+module.exports = exports['default'];