feat(form): add ability to reset a form to pristine state

Retting a form to pristine state will cause all of the nested
form and form controls to be recursively reset as well.

Closes #856

1 files changed, 16 insertions, 0 deletions

diff --git a/src/ng/directive/input.js b/src/ng/directive/input.js
index e17c12b3..695ca88a 100644
--- a/src/ng/directive/input.js
+++ b/src/ng/directive/input.js
@@ -978,6 +978,22 @@ var NgModelController = ['$scope', '$exceptionHandler', '$attrs', '$element', '$
     parentForm.$setValidity(validationErrorKey, isValid, this);
   };
 
+  /**
+   * @ngdoc function
+   * @name ng.directive:ngModel.NgModelController#$setPristine
+   * @methodOf ng.directive:ngModel.NgModelController
+   *
+   * @description
+   * Sets the control to its pristine state.
+   *
+   * This method can be called to remove the 'ng-dirty' class and set the control to its pristine
+   * state (ng-pristine class).
+   */
+  this.$setPristine = function () {
+    this.$dirty = false;
+    this.$pristine = true;
+    $element.removeClass(DIRTY_CLASS).addClass(PRISTINE_CLASS);
+  };
 
   /**
    * @ngdoc function