Prevent validation on disabled and hidden elements

disableValidation.js

    .directive('ignoreDisabled', ['$exceptionHandler', ($exceptionHandler) => {
        return {
            restrict: 'A',
            require: 'ngModel',
            link: ($scope, elem, attr, ctrl) => {
                if (!attr.hasOwnProperty('ngDisabled')) {
                    $exceptionHandler(new ReferenceError('Attempt to use ignoreDisabled on element without ngDisabled.'));
                } else {
                    $scope.$watch(attr.ngDisabled, (val, oldVal) => {
                        if (val === true && val !== oldVal) {
                            ctrl.$setUntouched();
                            ctrl.$setPristine();
                            Object.keys(ctrl.$validators)
                                .forEach((key) => ctrl.$setValidity(key, true));
                        } else {
                            Object.keys(ctrl.$validators)
                                .forEach((key) => ctrl.$setValidity(key, false));
                        }
                    });
                }
            }
        };
    }])