feat(BaseRequestOptions): add merge method to make copies of options

modules/angular2/src/http/base_request_options.ts

@@ -1,21 +1,34 @@
-import {CONST_EXPR, CONST} from 'angular2/src/facade/lang';
+import {CONST_EXPR, CONST, isPresent} from 'angular2/src/facade/lang';
 import {Headers} from './headers';
 import {URLSearchParams} from './url_search_params';
 import {RequestModesOpts, RequestMethods, RequestCacheOpts, RequestCredentialsOpts} from './enums';
 import {RequestOptions} from './interfaces';
 import {Injectable} from 'angular2/di';
+import {ListWrapper, StringMapWrapper} from 'angular2/src/facade/collection';
 
-@Injectable()
-export class BaseRequestOptions implements RequestOptions {
-  method: RequestMethods;
+export class RequestOptionsClass {
+  method: RequestMethods = RequestMethods.GET;
   headers: Headers;
   body: URLSearchParams | FormData | string;
-  mode: RequestModesOpts;
+  mode: RequestModesOpts = RequestModesOpts.Cors;
   credentials: RequestCredentialsOpts;
   cache: RequestCacheOpts;
+  constructor({method, headers, body, mode, credentials,
+               cache}: RequestOptions = {method: RequestMethods.GET, mode: RequestModesOpts.Cors}) {
+    this.method = method;
+    this.headers = headers;
+    this.body = body;
+    this.mode = mode;
+    this.credentials = credentials;
+    this.cache = cache;
+  }
 
-  constructor() {
-    this.method = RequestMethods.GET;
-    this.mode = RequestModesOpts.Cors;
+  merge(opts: RequestOptions = {}): RequestOptionsClass {
+    return new RequestOptionsClass(StringMapWrapper.merge(this, opts));
   }
 }
+
+@Injectable()
+export class BaseRequestOptions extends RequestOptionsClass {
+  constructor() { super(); }
+}

modules/angular2/test/http/base_request_options_spec.ts

@@ -0,0 +1,32 @@
+import {
+  AsyncTestCompleter,
+  beforeEach,
+  ddescribe,
+  describe,
+  expect,
+  iit,
+  inject,
+  it,
+  xit
+} from 'angular2/test_lib';
+import {BaseRequestOptions} from 'angular2/src/http/base_request_options';
+import {RequestMethods, RequestModesOpts} from 'angular2/src/http/enums';
+
+export function main() {
+  describe('BaseRequestOptions', () => {
+    it('should create a new object when calling merge', () => {
+      var options1 = new BaseRequestOptions();
+      var options2 = options1.merge({method: RequestMethods.DELETE});
+      expect(options2).not.toBe(options1);
+      expect(options2.method).toBe(RequestMethods.DELETE);
+    });
+
+    it('should retain previously merged values when merging again', () => {
+      var options1 = new BaseRequestOptions();
+      var options2 = options1.merge({method: RequestMethods.DELETE});
+      var options3 = options2.merge({mode: RequestModesOpts.NoCors}) expect(options3.mode)
+                         .toBe(RequestModesOpts.NoCors);
+      expect(options3.method).toBe(RequestMethods.DELETE);
+    });
+  });
+}