$rootScope.Scope.$watchCollection()

Shallow watches the properties of an object and fires whenever any of the properties change (for arrays, this implies watching the array items; for object maps, this implies watching the properties). If a change is detected, the listener callback is fired.

• The obj collection is observed via standard $watch operation and is examined on every call to $digest() to see if any items have been added, removed, or moved.
• The listener is called whenever anything within the obj has changed. Examples include adding, removing, and moving items belonging to an object or array.

$scope.names = ['igor', 'matias', 'misko', 'james'];
$scope.dataCount = 4;

$scope.$watchCollection('names', function(newNames, oldNames) {
  $scope.dataCount = newNames.length;
});

expect($scope.dataCount).toEqual(4);
$scope.$digest();

//still at 4 ... no changes
expect($scope.dataCount).toEqual(4);

$scope.names.pop();
$scope.$digest();

//now there's been a change
expect($scope.dataCount).toEqual(3);