test(matchers): add support for toHaveCssStyle matcher

modules/angular2/src/testing/matchers.dart

@@ -6,6 +6,8 @@ import 'package:guinness/guinness.dart' as gns;
 
 import 'package:angular2/src/platform/dom/dom_adapter.dart' show DOM;
 
+import 'package:angular2/src/facade/lang.dart' show isString;
+
 Expect expect(actual, [matcher]) {
   final expect = new Expect(actual);
   if (matcher != null) expect.to(matcher);
@@ -14,6 +16,18 @@ Expect expect(actual, [matcher]) {
 
 const _u = const Object();
 
+bool elementContainsStyle(element, styles) {
+  var allPassed = true;
+  if (isString(styles)) {
+    allPassed = DOM.hasStyle(element, styles);
+  } else {
+    styles.forEach((prop, style) {
+      allPassed = allPassed && DOM.hasStyle(element, prop, style);
+    });
+  }
+  return allPassed;
+}
+
 expectErrorMessage(actual, expectedMessage) {
   expect(actual.toString()).toContain(expectedMessage);
 }
@@ -38,6 +52,9 @@ class Expect extends gns.Expect {
   void toBePromise() => gns.guinness.matchers.toBeTrue(actual is Future);
   void toHaveCssClass(className) =>
       gns.guinness.matchers.toBeTrue(DOM.hasClass(actual, className));
+  void toHaveCssStyle(styles) {
+    gns.guinness.matchers.toBeTrue(elementContainsStyle(actual, styles));
+  }
   void toImplement(expected) => toBeA(expected);
   void toBeNaN() =>
       gns.guinness.matchers.toBeTrue(double.NAN.compareTo(actual) == 0);
@@ -78,6 +95,9 @@ class NotExpect extends gns.NotExpect {
   void toBePromise() => gns.guinness.matchers.toBeFalse(actual is Future);
   void toHaveCssClass(className) =>
       gns.guinness.matchers.toBeFalse(DOM.hasClass(actual, className));
+  void toHaveCssStyle(styles) {
+    gns.guinness.matchers.toBeFalse(elementContainsStyle(actual, styles));
+  }
   void toBeNull() => gns.guinness.matchers.toBeFalse(actual == null);
   Function get _expect => gns.guinness.matchers.expect;
 }

modules/angular2/src/testing/matchers.ts

@@ -1,5 +1,6 @@
 import {DOM} from 'angular2/src/platform/dom/dom_adapter';
-import {global} from 'angular2/src/facade/lang';
+import {global, isString} from 'angular2/src/facade/lang';
+import {StringMapWrapper} from 'angular2/src/facade/collection';
 
 
 export interface NgMatchers extends jasmine.Matchers {
@@ -7,6 +8,7 @@ export interface NgMatchers extends jasmine.Matchers {
   toBeAnInstanceOf(expected: any): boolean;
   toHaveText(expected: any): boolean;
   toHaveCssClass(expected: any): boolean;
+  toHaveCssStyle(expected: any): boolean;
   toImplement(expected: any): boolean;
   toContainError(expected: any): boolean;
   toThrowErrorWith(expectedMessage: any): boolean;
@@ -105,6 +107,31 @@ _global.beforeEach(function() {
       }
     },
 
+    toHaveCssStyle: function() {
+      return {
+        compare: function(actual, styles) {
+          var allPassed;
+          if (isString(styles)) {
+            allPassed = DOM.hasStyle(actual, styles);
+          } else {
+            allPassed = !StringMapWrapper.isEmpty(styles);
+            StringMapWrapper.forEach(styles, (style, prop) => {
+              allPassed = allPassed && DOM.hasStyle(actual, prop, style);
+            });
+          }
+
+          return {
+            pass: allPassed,
+            get message() {
+              var expectedValueStr = isString(styles) ? styles : JSON.stringify(styles);
+              return `Expected ${actual.outerHTML} ${!allPassed ? ' ' : 'not '}to contain the
+                      CSS ${isString(styles) ? 'property' : 'styles'} "${expectedValueStr}"`;
+            }
+          };
+        }
+      };
+    },
+
     toContainError: function() {
       return {
         compare: function(actual, expectedText) {