Numbers only in text input - Angular directive

numbersOnly.js

'use strict';

angular.module('myApp').directive('numbersOnly', function () {
   return {
       restrict: 'A',
       require: 'ngModel',
       scope: {
           options: '=numbersOnly'
       },
       link: function (scope, element, attrs, ngModel) {

           /* istanbul ignore if */
           if (!ngModel) {
               return;
           }

           var min = (scope.options && scope.options.min) ? scope.options.min : null;
           var max = (scope.options && scope.options.max) ? scope.options.max : null;

           ngModel.$formatters.push(parseValue);
           ngModel.$parsers.push(parseValue);

           function parseValue(inputValue)
           {
               ngModel.$setValidity('invalidMinimum', true);
               ngModel.$setValidity('invalidMaximum', true);

               if (inputValue) {

                   // if initial loading of the model, and there was no value previously set, remove invalid
                   var resetInvalid = (isNaN(ngModel.$viewValue));

                   // strip out anything thats not a number
                   inputValue = inputValue.replace(/[^0-9]/, '');

                   // check for minimum
                   if (min != null && parseInt(inputValue) < min) {
                       ngModel.$setValidity('invalidMinimum', false);
                       /* istanbul ignore if */
                       if (resetInvalid) inputValue = '';
                   }

                   // check for maximum
                   if (max != null && parseInt(inputValue) > max) {
                       ngModel.$setValidity('invalidMaximum', false);
                       /* istanbul ignore if */
                       if (resetInvalid) inputValue = '';
                   }

                   ngModel.$setViewValue(inputValue);
                   ngModel.$render();
                   ngModel.$validate();
               }

               return inputValue;
           }
       }
   };

});