feat($animate): animate dirty, pristine, valid, invalid for form/fields

Add css animations when form or field status change to/from dirty,
pristine, valid or invalid. This works like animation system present
with ngClass, ngShow, etc.

Closes angular#5378

src/ng/directive/form.js

@@ -46,8 +46,8 @@ var nullFormCtrl = {
  *
  */
 //asks for $scope to fool the BC controller module
-FormController.$inject = ['$element', '$attrs', '$scope'];
-function FormController(element, attrs) {
+FormController.$inject = ['$element', '$attrs', '$scope', '$animate'];
+function FormController(element, attrs, $scope, $animate) {
   var form = this,
       parentForm = element.parent().controller('form') || nullFormCtrl,
       invalidCount = 0, // used to easily determine if we are valid
@@ -70,9 +70,8 @@ function FormController(element, attrs) {
   // convenience method for easy toggling of classes
   function toggleValidCss(isValid, validationErrorKey) {
     validationErrorKey = validationErrorKey ? '-' + snake_case(validationErrorKey, '-') : '';
-    element.
-      removeClass((isValid ? INVALID_CLASS : VALID_CLASS) + validationErrorKey).
-      addClass((isValid ? VALID_CLASS : INVALID_CLASS) + validationErrorKey);
+    $animate.removeClass(element, (isValid ? INVALID_CLASS : VALID_CLASS) + validationErrorKey);
+    $animate.addClass(element, (isValid ? VALID_CLASS : INVALID_CLASS) + validationErrorKey);
   }
 
   /**
@@ -173,7 +172,8 @@ function FormController(element, attrs) {
    * state (ng-dirty class). This method will also propagate to parent forms.
    */
   form.$setDirty = function() {
-    element.removeClass(PRISTINE_CLASS).addClass(DIRTY_CLASS);
+    $animate.removeClass(element, PRISTINE_CLASS);
+    $animate.addClass(element, DIRTY_CLASS);
     form.$dirty = true;
     form.$pristine = false;
     parentForm.$setDirty();
@@ -194,7 +194,8 @@ function FormController(element, attrs) {
    * saving or resetting it.
    */
   form.$setPristine = function () {
-    element.removeClass(DIRTY_CLASS).addClass(PRISTINE_CLASS);
+    $animate.removeClass(element, DIRTY_CLASS);
+    $animate.addClass(element, PRISTINE_CLASS);
     form.$dirty = false;
     form.$pristine = true;
     forEach(controls, function(control) {
@@ -249,6 +250,8 @@ function FormController(element, attrs) {
  *  - `ng-pristine` is set if the form is pristine.
  *  - `ng-dirty` is set if the form is dirty.
  *
+ * Keep in mind that ngAnimate can detect each of these classes when added and removed.
+ *
  *
  * # Submitting a form and preventing the default action
  *
@@ -279,18 +282,48 @@ function FormController(element, attrs) {
  * hitting enter in any of the input fields will trigger the click handler on the *first* button or
  * input[type=submit] (`ngClick`) *and* a submit handler on the enclosing form (`ngSubmit`)
  *
- * @param {string=} name Name of the form. If specified, the form controller will be published into
- *                       related scope, under this name.
+ * ## Animation Hooks
+ *
+ * Animations in ngForm are triggered when any of the associated CSS classes are added and removed. These
+ * classes are: `.pristine`, `.dirty`, `.invalid` and `.valid` as well as any other validations that
+ * are performed within the form. Animations in ngForm are similar to how they work in ngClass and
+ * animations can be hooked into using CSS transitions, keyframes as well as JS animations.
+ *
+ * The following example shows a simple way to utilize CSS transitions to style a form element
+ * that has been rendered as invalid after it has been validated:
+ *
+ * <pre>
+ * //be sure to include ngAnimate as a module to hook into more
+ * //advanced animations
+ * .my-form {
+ *   transition:0.5s linear all;
+ *   background: white;
+ * }
+ * .my-form.ng-invalid {
+ *   background: red;
+ *   color:white;
+ * }
+ * </pre>
  *
  * @example
-    <example>
+    <example deps="angular-animate.js" animations="true" fixBase="true">
       <file name="index.html">
        <script>
          function Ctrl($scope) {
            $scope.userType = 'guest';
          }
        </script>
-       <form name="myForm" ng-controller="Ctrl">
+       <style>
+        .my-form {
+          -webkit-transition:all linear 0.5s;
+          transition:all linear 0.5s;
+          background: transparent;
+        }
+        .my-form.ng-invalid {
+          background: red;
+        }
+       </style>
+       <form name="myForm" ng-controller="Ctrl" class="my-form">
          userType: <input name="input" ng-model="userType" required>
          <span class="error" ng-show="myForm.input.$error.required">Required!</span><br>
          <tt>userType = {{userType}}</tt><br>
@@ -322,6 +355,9 @@ function FormController(element, attrs) {
         });
       </file>
     </example>
+ *
+ * @param {string=} name Name of the form. If specified, the form controller will be published into
+ *                       related scope, under this name.
  */
 var formDirectiveFactory = function(isNgForm) {
   return ['$timeout', function($timeout) {

src/ng/directive/input.js

@@ -1003,8 +1003,8 @@ var VALID_CLASS = 'ng-valid',
  *
  *
  */
-var NgModelController = ['$scope', '$exceptionHandler', '$attrs', '$element', '$parse',
-    function($scope, $exceptionHandler, $attr, $element, $parse) {
+var NgModelController = ['$scope', '$exceptionHandler', '$attrs', '$element', '$parse', '$animate',
+    function($scope, $exceptionHandler, $attr, $element, $parse, $animate) {
   this.$viewValue = Number.NaN;
   this.$modelValue = Number.NaN;
   this.$parsers = [];
@@ -1067,9 +1067,8 @@ var NgModelController = ['$scope', '$exceptionHandler', '$attrs', '$element', '$
   // convenience method for easy toggling of classes
   function toggleValidCss(isValid, validationErrorKey) {
     validationErrorKey = validationErrorKey ? '-' + snake_case(validationErrorKey, '-') : '';
-    $element.
-      removeClass((isValid ? INVALID_CLASS : VALID_CLASS) + validationErrorKey).
-      addClass((isValid ? VALID_CLASS : INVALID_CLASS) + validationErrorKey);
+    $animate.removeClass($element, (isValid ? INVALID_CLASS : VALID_CLASS) + validationErrorKey);
+    $animate.addClass($element, (isValid ? VALID_CLASS : INVALID_CLASS) + validationErrorKey);
   }
 
   /**
@@ -1128,7 +1127,8 @@ var NgModelController = ['$scope', '$exceptionHandler', '$attrs', '$element', '$
   this.$setPristine = function () {
     this.$dirty = false;
     this.$pristine = true;
-    $element.removeClass(DIRTY_CLASS).addClass(PRISTINE_CLASS);
+    $animate.removeClass($element, DIRTY_CLASS);
+    $animate.addClass($element, PRISTINE_CLASS);
   };
 
   /**
@@ -1159,7 +1159,8 @@ var NgModelController = ['$scope', '$exceptionHandler', '$attrs', '$element', '$
     if (this.$pristine) {
       this.$dirty = true;
       this.$pristine = false;
-      $element.removeClass(PRISTINE_CLASS).addClass(DIRTY_CLASS);
+      $animate.removeClass($element, PRISTINE_CLASS);
+      $animate.addClass($element, DIRTY_CLASS);
       parentForm.$setDirty();
     }
 
@@ -1225,7 +1226,7 @@ var NgModelController = ['$scope', '$exceptionHandler', '$attrs', '$element', '$
  *   require.
  * - Providing validation behavior (i.e. required, number, email, url).
  * - Keeping the state of the control (valid/invalid, dirty/pristine, validation errors).
- * - Setting related css classes on the element (`ng-valid`, `ng-invalid`, `ng-dirty`, `ng-pristine`).
+ * - Setting related css classes on the element (`ng-valid`, `ng-invalid`, `ng-dirty`, `ng-pristine`) including animations.
  * - Registering the control with its parent {@link ng.directive:form form}.
  *
  * Note: `ngModel` will try to bind to the property given by evaluating the expression on the
@@ -1248,6 +1249,67 @@ var NgModelController = ['$scope', '$exceptionHandler', '$attrs', '$element', '$
  *  - {@link ng.directive:select select}
  *  - {@link ng.directive:textarea textarea}
  *
+ * # CSS classes
+ * The following CSS classes are added and removed on the associated input/select/textarea element
+ * depending on the validity of the model.
+ *
+ *  - `ng-valid` is set if the model is valid.
+ *  - `ng-invalid` is set if the model is invalid.
+ *  - `ng-pristine` is set if the model is pristine.
+ *  - `ng-dirty` is set if the model is dirty.
+ *
+ * Keep in mind that ngAnimate can detect each of these classes when added and removed.
+ *
+ * ## Animation Hooks
+ *
+ * Animations within models are triggered when any of the associated CSS classes are added and removed
+ * on the input element which is attached to the model. These classes are: `.pristine`, `.dirty`,
+ * `.invalid` and `.valid` as well as any other validations that are performed on the model itself.
+ * The animations that are triggered within ngModel are similar to how they work in ngClass and
+ * animations can be hooked into using CSS transitions, keyframes as well as JS animations.
+ *
+ * The following example shows a simple way to utilize CSS transitions to style an input element
+ * that has been rendered as invalid after it has been validated:
+ *
+ * <pre>
+ * //be sure to include ngAnimate as a module to hook into more
+ * //advanced animations
+ * .my-input {
+ *   transition:0.5s linear all;
+ *   background: white;
+ * }
+ * .my-input.ng-invalid {
+ *   background: red;
+ *   color:white;
+ * }
+ * </pre>
+ *
+ * @example
+ * <example deps="angular-animate.js" animations="true" fixBase="true">
+     <file name="index.html">
+       <script>
+        function Ctrl($scope) {
+          $scope.val = '1';
+        }
+       </script>
+       <style>
+         .my-input {
+           -webkit-transition:all linear 0.5s;
+           transition:all linear 0.5s;
+           background: transparent;
+         }
+         .my-input.ng-invalid {
+           color:white;
+           background: red;
+         }
+       </style>
+       Update input to see transitions when valid/invalid.
+       Integer is a valid value.
+       <form name="testForm" ng-controller="Ctrl">
+         <input ng-model="val" ng-pattern="/^\d+$/" name="anim" class="my-input" />
+       </form>
+     </file>
+ * </example>
  */
 var ngModelDirective = function() {
   return {

src/ngAnimate/animate.js

@@ -31,6 +31,8 @@
  * | {@link ng.directive:ngIf#usage_animations ngIf}                 | enter and leave                                    |
  * | {@link ng.directive:ngClass#usage_animations ngClass}           | add and remove                                     |
  * | {@link ng.directive:ngShow#usage_animations ngShow & ngHide}    | add and remove (the ng-hide class value)           |
+ * | {@link ng.directive:form#usage_animations form}                 | dirty, pristine, valid and invalid                 |
+ * | {@link ng.directive:ngModel#usage_animations ngModel}           | dirty, pristine, valid and invalid                 |
  *
  * You can find out more information about animations upon visiting each directive page.
  *

test/ng/directive/formSpec.js

@@ -594,3 +594,83 @@ describe('form', function() {
     });
   });
 });
+
+describe('form animations', function() {
+  beforeEach(module('ngAnimateMock'));
+
+  function assertValidAnimation(animation, event, className) {
+    expect(animation.event).toBe(event);
+    expect(animation.args[1]).toBe(className);
+  }
+
+  var doc, scope, form;
+  beforeEach(inject(function($rootScope, $compile, $rootElement, $animate) {
+    scope = $rootScope.$new();
+    doc = jqLite('<form name="myForm"></form>');
+    $rootElement.append(doc);
+    $compile(doc)(scope);
+    $animate.queue = [];
+    form = scope.myForm;
+  }));
+
+  afterEach(function() {
+    dealoc(doc);
+  });
+
+  it('should trigger an animation when invalid', inject(function($animate) {
+    form.$setValidity('required', false);
+
+    assertValidAnimation($animate.queue[0], 'removeClass', 'ng-valid');
+    assertValidAnimation($animate.queue[1], 'addClass', 'ng-invalid');
+    assertValidAnimation($animate.queue[2], 'removeClass', 'ng-valid-required');
+    assertValidAnimation($animate.queue[3], 'addClass', 'ng-invalid-required');
+  }));
+
+  it('should trigger an animation when valid', inject(function($animate) {
+    form.$setValidity('required', false);
+
+    $animate.queue = [];
+
+    form.$setValidity('required', true);
+
+    assertValidAnimation($animate.queue[0], 'removeClass', 'ng-invalid');
+    assertValidAnimation($animate.queue[1], 'addClass', 'ng-valid');
+    assertValidAnimation($animate.queue[2], 'removeClass', 'ng-invalid-required');
+    assertValidAnimation($animate.queue[3], 'addClass', 'ng-valid-required');
+  }));
+
+  it('should trigger an animation when dirty', inject(function($animate) {
+    form.$setDirty();
+
+    assertValidAnimation($animate.queue[0], 'removeClass', 'ng-pristine');
+    assertValidAnimation($animate.queue[1], 'addClass', 'ng-dirty');
+  }));
+
+  it('should trigger an animation when pristine', inject(function($animate) {
+    form.$setDirty();
+
+    $animate.queue = [];
+
+    form.$setPristine();
+
+    assertValidAnimation($animate.queue[0], 'removeClass', 'ng-dirty');
+    assertValidAnimation($animate.queue[1], 'addClass', 'ng-pristine');
+  }));
+
+  it('should trigger custom errors as addClass/removeClass when invalid/valid', inject(function($animate) {
+    form.$setValidity('custom-error', false);
+
+    assertValidAnimation($animate.queue[0], 'removeClass', 'ng-valid');
+    assertValidAnimation($animate.queue[1], 'addClass', 'ng-invalid');
+    assertValidAnimation($animate.queue[2], 'removeClass', 'ng-valid-custom-error');
+    assertValidAnimation($animate.queue[3], 'addClass', 'ng-invalid-custom-error');
+
+    $animate.queue = [];
+    form.$setValidity('custom-error', true);
+
+    assertValidAnimation($animate.queue[0], 'removeClass', 'ng-invalid');
+    assertValidAnimation($animate.queue[1], 'addClass', 'ng-valid');
+    assertValidAnimation($animate.queue[2], 'removeClass', 'ng-invalid-custom-error');
+    assertValidAnimation($animate.queue[3], 'addClass', 'ng-valid-custom-error');
+  }));
+});