Make sure watches are fired after any other directives that affect the ngModel value
function(elem, attr) {
      if (attr.hasOwnProperty(ARIA_DISABLE_ATTR)) return;

      var shape = getShape(attr, elem);

      return {
        post: function(scope, elem, attr, ngModel) {
          var needsTabIndex = shouldAttachAttr('tabindex', 'tabindex', elem, false);

          function ngAriaWatchModelValue() {
            return ngModel.$modelValue;
          }

          function getRadioReaction(newVal) {
            // Strict comparison would cause a BC
            // eslint-disable-next-line eqeqeq
            var boolVal = (attr.value == ngModel.$viewValue);
            elem.attr('aria-checked', boolVal);
          }

          function getCheckboxReaction() {
            elem.attr('aria-checked', !ngModel.$isEmpty(ngModel.$viewValue));
          }

          switch (shape) {
            case 'radio':
            case 'checkbox':
              if (shouldAttachRole(shape, elem)) {
                elem.attr('role', shape);
              }
              if (shouldAttachAttr('aria-checked', 'ariaChecked', elem, false)) {
                scope.$watch(ngAriaWatchModelValue, shape === 'radio' ?
                    getRadioReaction : getCheckboxReaction);
              }
              if (needsTabIndex) {
                elem.attr('tabindex', 0);
              }
              break;
            case 'range':
              if (shouldAttachRole(shape, elem)) {
                elem.attr('role', 'slider');
              }
              if ($aria.config('ariaValue')) {
                var needsAriaValuemin = !elem.attr('aria-valuemin') &&
                    (attr.hasOwnProperty('min') || attr.hasOwnProperty('ngMin'));
                var needsAriaValuemax = !elem.attr('aria-valuemax') &&
                    (attr.hasOwnProperty('max') || attr.hasOwnProperty('ngMax'));
                var needsAriaValuenow = !elem.attr('aria-valuenow');

                if (needsAriaValuemin) {
                  attr.$observe('min', function ngAriaValueMinReaction(newVal) {
                    elem.attr('aria-valuemin', newVal);
                  });
                }
                if (needsAriaValuemax) {
                  attr.$observe('max', function ngAriaValueMinReaction(newVal) {
                    elem.attr('aria-valuemax', newVal);
                  });
                }
                if (needsAriaValuenow) {
                  scope.$watch(ngAriaWatchModelValue, function ngAriaValueNowReaction(newVal) {
                    elem.attr('aria-valuenow', newVal);
                  });
                }
              }
              if (needsTabIndex) {
                elem.attr('tabindex', 0);
              }
              break;
          }

          if (!attr.hasOwnProperty('ngRequired') && ngModel.$validators.required
            && shouldAttachAttr('aria-required', 'ariaRequired', elem, false)) {
            // ngModel.$error.required is undefined on custom controls
            attr.$observe('required', function() {
              elem.attr('aria-required', !!attr['required']);
            });
          }

          if (shouldAttachAttr('aria-invalid', 'ariaInvalid', elem, true)) {
            scope.$watch(function ngAriaInvalidWatch() {
              return ngModel.$invalid;
            }, function ngAriaInvalidReaction(newVal) {
              elem.attr('aria-invalid', !!newVal);
            });
          }
        }
      };
    }