added throwing error from angular digest cycle

Author: bahmutov

README.md

@@ -77,6 +77,8 @@ digest duration for several selectors and print sorted table starting with the s
 * [ng-count-digest-cycles.js](ng-count-digest-cycles.js) - counts number of full digest cycles (from the root scope)
 that run when a scope method executes. Useful because sometimes you can get away with just a local digest
 cycle, rather than a full update. See [Local Angular scopes](http://glebbahmutov.com/blog/local-angular-scopes/).
+* [ng-throw-error.js](ng-throw-error.js) throws an error from the digest cycle; useful for checking
+if your [exception handler](http://glebbahmutov.com/blog/catch-all-errors-in-angular-app/) is working.
 
 All snippets, including mine are distributed under MIT license.
 

ng-throw-error.js

@@ -0,0 +1,19 @@
+// throws an exception from the digest cycle
+// useful to test your exception handler service
+// http://glebbahmutov.com/blog/catch-all-errors-in-angular-app/
+(function throwErrorFromAngular(angular) {
+
+  if (typeof angular === 'undefined') {
+    throw new Error('Cannot find angular on the page');
+  }
+  // select any element in the Elements panel that is inside Angular app
+  /* global $0 */
+  var injector = angular.element($0).injector();
+  if (!injector) {
+    throw new Error('Cannot find injector, please select an element\n' +
+      'INSIDE an angular app in the Elements panel');
+  }
+  injector.get('$rootScope').$apply(function () {
+    throw new Error('Error from Angular digest cycle');
+  });
+}(window.angular));