test(matchers): add support for toMatchPattern in tests

modules/angular2/src/testing/matchers.dart

@@ -55,6 +55,8 @@ class Expect extends gns.Expect {
   void toHaveCssStyle(styles) {
     gns.guinness.matchers.toBeTrue(elementContainsStyle(actual, styles));
   }
+  void toMatchPattern(pattern) =>
+      gns.guinness.matchers.toBeTrue(pattern.hasMatch(actual));
   void toImplement(expected) => toBeA(expected);
   void toBeNaN() =>
       gns.guinness.matchers.toBeTrue(double.NAN.compareTo(actual) == 0);
@@ -98,6 +100,8 @@ class NotExpect extends gns.NotExpect {
   void toHaveCssStyle(styles) {
     gns.guinness.matchers.toBeFalse(elementContainsStyle(actual, styles));
   }
+  void toMatchPattern(pattern) =>
+      gns.guinness.matchers.toBeFalse(pattern.hasMatch(actual));
   void toBeNull() => gns.guinness.matchers.toBeFalse(actual == null);
   Function get _expect => gns.guinness.matchers.expect;
 }

modules/angular2/src/testing/matchers.ts

@@ -78,6 +78,15 @@ export interface NgMatchers extends jasmine.Matchers {
    */
   toThrowErrorWith(expectedMessage: any): boolean;
 
+  /**
+   * Expect a string to match the given regular expression.
+   *
+   * ## Example
+   *
+   * {@example testing/ts/matchers.ts region='toMatchPattern'}
+   */
+  toMatchPattern(expectedMessage: any): boolean;
+
   /**
    * Invert the matchers.
    */
@@ -240,6 +249,21 @@ _global.beforeEach(function() {
       };
     },
 
+    toMatchPattern() {
+      return {compare: buildError(false), negativeCompare: buildError(true)};
+
+      function buildError(isNot) {
+        return function(actual, regex) {
+          return {
+            pass: regex.test(actual) == !isNot,
+            get message() {
+              return `Expected ${actual} ${isNot ? 'not ' : ''}to match ${regex.toString()}`;
+            }
+          };
+        };
+      }
+    },
+
     toImplement: function() {
       return {
         compare: function(actualObject, expectedInterface) {

modules/angular2/test/testing/testing_internal_spec.ts

@@ -54,6 +54,14 @@ export function main() {
       });
     });
 
+    describe("toMatchPAttern", () => {
+      it("should assert that a string matches a given pattern", () => {
+        expect("matias").toMatchPattern(/ias$/g);
+        expect("tobias").toMatchPattern(/ias$/g);
+        expect("joonas").not.toMatchPattern(/ias$/g);
+      });
+    });
+
     describe('toEqual for Maps', () => {
       it('should detect equality for same reference', () => {
         var m1 = MapWrapper.createFromStringMap({'a': 1});