feat(ngMock) add atomic flushing strategy for $timeout

src/ngMock/angular-mocks.js

@@ -103,8 +103,11 @@ angular.mock.$Browser = function() {
    * Flushes all pending requests and executes the defer callbacks.
    *
    * @param {number=} number of milliseconds to flush. See {@link #defer.now}
+   * @param {boolean=} [atomic=false] If set to `true` — will handle only tasks
+   * available at the moment of execution, otherwise will process tasks that were
+   * added during execution as well.
    */
-  self.defer.flush = function(delay) {
+  self.defer.flush = function(delay, atomic) {
     if (angular.isDefined(delay)) {
       self.defer.now += delay;
     } else {
@@ -115,8 +118,25 @@ angular.mock.$Browser = function() {
       }
     }
 
-    while (self.deferredFns.length && self.deferredFns[0].time <= self.defer.now) {
-      self.deferredFns.shift().fn();
+    function shiftExecutableFns(handler) {
+      while (self.deferredFns.length && self.deferredFns[0].time <= self.defer.now) {
+        handler(self.deferredFns.shift());
+      }
+    }
+
+    if (atomic) {
+      var fnsToRun = [];
+      shiftExecutableFns(function(task) {
+        fnsToRun.push(task);
+      });
+
+      angular.forEach(fnsToRun, function(item) {
+        item.fn();
+      });
+    } else {
+      shiftExecutableFns(function(task) {
+        task.fn();
+      });
     }
   };
 
@@ -1948,9 +1968,11 @@ angular.mock.$TimeoutDecorator = ['$delegate', '$browser', function($delegate, $
    * Flushes the queue of pending tasks.
    *
    * @param {number=} delay maximum timeout amount to flush up until
+   * @param {boolean=} [atomic=false] If set to `true` — will not run the tasks
+   * added during execution of flush even if they were added with `0` timeout.
    */
-  $delegate.flush = function(delay) {
-    $browser.defer.flush(delay);
+  $delegate.flush = function(delay, atomic) {
+    $browser.defer.flush(delay, atomic);
   };
 
   /**

test/ngMock/angular-mocksSpec.js

@@ -690,6 +690,40 @@ describe('ngMock', function() {
       $timeout.flush(123);
       expect(count).toBe(2);
     }));
+
+    it('should process dynamically added tasks one per each flush,' +
+    ' if called in atomic mode', inject(function($timeout) {
+
+      var task1 = jasmine.createSpy('first handler');
+      var task2 = jasmine.createSpy('second handler');
+
+      $timeout(function() {
+        task1();
+        $timeout(function() {
+          task2();
+        });
+      });
+
+      $timeout.flush(0, true);
+      expect(task1).toHaveBeenCalled();
+      expect(task2).not.toHaveBeenCalled();
+
+      $timeout.flush(0);
+      expect(task2).toHaveBeenCalled();
+
+    }));
+
+    it('should process dynamically added tasks by default', inject(function($timeout) {
+      var nestedTask = jasmine.createSpy('handler behind the nested timeouts');
+      $timeout(function() {
+        $timeout(function() {
+          nestedTask();
+        });
+      });
+
+      $timeout.flush(0);
+      expect(nestedTask).toHaveBeenCalled();
+    }));
   });