[no-issue] Order Decorator

- added @OrderDecorator and OrderUtil
- added tests for OrderDecorator and OrderUtil
- exported the decorator
[reviewed by @saskodh]

Author: draganAndonovski

src/index.ts

@@ -19,4 +19,5 @@ export {ApplicationContext} from "./lib/di/ApplicationContext";
 export {Dispatcher} from "./lib/dispatcher/Dispatcher";
 export {Interceptor} from "./lib/interceptors/InterceptorDecorator";
 export {ComponentDefinitionPostProcessor} from "./lib/processors/ComponentDefinitionPostProcessor";
-export {ComponentPostProcessor} from "./lib/processors/ComponentPostProcessor";
+export {ComponentPostProcessor} from "./lib/processors/ComponentPostProcessor";
+export {Order} from "./lib/decorators/OrderDecorator";

src/lib/decorators/OrderDecorator.ts

@@ -0,0 +1,20 @@
+import * as _ from "lodash";
+
+const ORDER_DECORATOR_TOKEN = Symbol('order_decorator_token');
+
+export function Order(orderValue) {
+    return function(target) {
+        target[ORDER_DECORATOR_TOKEN] = orderValue;
+    };
+}
+
+export class OrderUtil {
+
+    static getOrder (target) {
+        return target[ORDER_DECORATOR_TOKEN];
+    }
+
+    static orderList (list): Array<any> {
+        return _.sortBy(list, (element) => { return OrderUtil.getOrder(element) || Number.MAX_VALUE; });
+    }
+}

test/lib/decorators/OrderDecorator.spec.ts

@@ -0,0 +1,50 @@
+import { expect } from "chai";
+import { Order, OrderUtil } from "../../../src/lib/decorators/OrderDecorator";
+
+describe('OrderDecorator', function () {
+
+    it('should add metadata', function () {
+        // given
+        @Order(1)
+        class A {}
+
+        // when
+        let orderValue = OrderUtil.getOrder(A);
+
+        // then
+        expect(orderValue).to.be.eq(1);
+    });
+});
+
+describe('OrderUtil', function () {
+
+    it('should return metadata', function () {
+        // given
+        @Order(1)
+        class A {}
+
+        class B {}
+
+        // when / then
+        expect(OrderUtil.getOrder(A)).to.be.eq(1);
+        expect(OrderUtil.getOrder(B)).to.be.undefined;
+    });
+
+    it('should order given list according to the value passed with the @Order decorator', function () {
+        // given
+        @Order(5)
+        class A {}
+
+        @Order(1)
+        class B {}
+
+        class C {}
+        let list = [A, B, C];
+
+        // when
+        let orderedList = OrderUtil.orderList(list);
+
+        // then
+        expect(orderedList).to.be.eql([B, A, C]);
+    });
+});