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

node_modules/async/internal/reject.js

@@ -0,0 +1,21 @@
+'use strict';
+
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+exports.default = reject;
+
+var _filter = require('./filter');
+
+var _filter2 = _interopRequireDefault(_filter);
+
+function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
+
+function reject(eachfn, arr, iteratee, callback) {
+    (0, _filter2.default)(eachfn, arr, function (value, cb) {
+        iteratee(value, function (err, v) {
+            cb(err, !v);
+        });
+    }, callback);
+}
+module.exports = exports['default'];