adds ErrorFactory function

index.es6.js

@@ -2,10 +2,12 @@ import Model from './src/Model';
 import Collection from './src/Collection';
 import Enum from './src/Enum';
 import Serializable from './src/Serializable';
+import ErrorFactory from './src/ErrorFactory';
 
 export {
   Model,
   Collection,
   Enum,
-  Serializable
+  Serializable,
+  ErrorFactory
 }

index.js

@@ -4,10 +4,12 @@ const Model = require('./lib/Model');
 const Collection = require('./lib/Collection');
 const Enum = require('./lib/Enum');
 const Serializable = require('./lib/Serializable');
+const ErrorFactory = require('./lib/ErrorFactory');
 
 module.exports = {
   Model: Model.default,
   Collection: Collection.default,
   Enum: Enum.default,
-  Serializable: Serializable.default
+  Serializable: Serializable.default,
+  ErrorFactory: ErrorFactory.default
 }

index.mjs

@@ -1,4 +1,5 @@
 export Model from './src/Model';
 export Collection from './src/Collection';
 export Enum from './src/Enum';
-export Serializable from './src/Serializable';
+export Serializable from './src/Serializable';
+export ErrorFactory from './src/ErrorFactory';

src/ErrorFactory.js

@@ -0,0 +1,17 @@
+/**
+ *
+ * construct a custom error constructor and streamline
+ *   the stack trace captured in the custom error
+ *
+ * @param {ErrorConstructor} (ErrorClass) [Error]
+ * @returns {Error}
+ *
+ */
+export default function ErrorFactory(ErrorClass=Error) {
+  return class CustomError extends ErrorClass {
+    constructor(...args) {
+      super(...args);
+      Error.captureStackTrace(this, CustomError);
+    }
+  }
+}

tests/errorfactor.spec.js

@@ -0,0 +1,21 @@
+import test from 'ava';
+import faker from 'faker';
+import ErrorFactory from '../src/ErrorFactory';
+
+test.beforeEach(t => {
+  const text = faker.random.word();
+  const ErrorConstructor = ErrorFactory();
+  const Error = new ErrorConstructor(text);
+  t.context = {
+    ErrorConstructor,
+    Error,
+    text
+  };
+});
+
+test('ErrorFactory() should return an Error Constructor', t => {
+  t.is(typeof ErrorFactory, 'function');
+  t.is(typeof t.context.ErrorConstructor, 'function');
+  t.is(typeof t.context.Error, 'object');
+  t.is(t.context.Error.message, t.context.text);
+});