feat(form.FormController): add $getControls()

Closes angular#16601
Fixes angular#14749
Closes angular#14517
Closes angular#13202

Author: Narretz

src/ng/directive/form.js

@@ -4,6 +4,7 @@
  */
 var nullFormCtrl = {
   $addControl: noop,
+  $getControls: valueFn([]),
   $$renameControl: nullFormRenameControl,
   $removeControl: noop,
   $setValidity: noop,
@@ -159,6 +160,30 @@ FormController.prototype = {
     control.$$parentForm = this;
   },
 
+  /**
+   * @ngdoc method
+   * @name form.FormController#$getControls
+   * @returns {Array} the controls that are currently part of this form
+   *
+   * @description
+   * This method returns a **shallow copy** of the controls that are currently part of this form.
+   * The controls can be instances of {@link form.FormController `FormController`}
+   * ({@link ngForm "child-forms"}) and of {@link ngModel.NgModelController `NgModelController`}.
+   * If you need access to the controls of child-forms, you have to call `$getControls()`
+   * recursively on them.
+   * This can be used for example to iterate over all controls to validate them.
+   *
+   * The controls can be accessed normally, but adding to, or removing controls from the array has
+   * no effect on the form. Instead, use {@link form.FormController#$addControl `$addControl()`} and
+   * {@link form.FormController#$removeControl `$removeControl()`} for this use-case.
+   * Likewise, adding a control to, or removing a control from the form is not reflected
+   * in the shallow copy. That means you should get a fresh copy from `$getControls()` every time
+   * you need access to the controls.
+   */
+  $getControls: function() {
+    return shallowCopy(this.$$controls);
+  },
+
   // Private API: rename a form control
   $$renameControl: function(control, newName) {
     var oldName = control.$name;

test/ng/directive/formSpec.js

@@ -1200,6 +1200,52 @@ describe('form', function() {
     });
   });
 
+  describe('$getControls', function() {
+    it('should return an empty array if the controller has no controls', function() {
+      doc = $compile('<form name="testForm"></form>')(scope);
+
+      scope.$digest();
+
+      var formCtrl = scope.testForm;
+
+      expect(formCtrl.$getControls()).toEqual([]);
+    });
+
+    it('should return a shallow copy of the form controls', function() {
+      doc = $compile(
+          '<form name="testForm">' +
+            '<input ng-model="named" name="foo">' +
+            '<div ng-form>' +
+              '<input ng-model="named" name="foo">' +
+            '</div>' +
+          '</form>')(scope);
+
+      scope.$digest();
+
+      var form = doc,
+          formCtrl = scope.testForm,
+          formInput = form.children('input').eq(0),
+          formInputCtrl = formInput.controller('ngModel'),
+          nestedForm = form.find('div'),
+          nestedFormCtrl = nestedForm.controller('form'),
+          nestedInput = nestedForm.children('input').eq(0),
+          nestedInputCtrl = nestedInput.controller('ngModel');
+
+      var controls = formCtrl.$getControls();
+
+      expect(controls).not.toBe(formCtrl.$$controls);
+
+      controls.push('something');
+      expect(formCtrl.$$controls).not.toContain('something');
+
+      expect(controls[0]).toBe(formInputCtrl);
+      expect(controls[1]).toBe(nestedFormCtrl);
+
+      var nestedControls = controls[1].$getControls();
+
+      expect(nestedControls[0]).toBe(nestedInputCtrl);
+    });
+  });
 
   it('should rename nested form controls when interpolated name changes', function() {
     scope.idA = 'A';