From 5496ce7031af5de104687027f1abaebf11f10c43 Mon Sep 17 00:00:00 2001
From: Casey Holzer <caseyh@snapappointments.com>
Date: Tue, 11 Dec 2018 12:04:55 -0700
Subject: [PATCH] add classList support for IE 8 & 9. #2151

---
 js/bootstrap-select.js | 53 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 53 insertions(+)

diff --git a/js/bootstrap-select.js b/js/bootstrap-select.js
index edb80723b..054f13618 100644
--- a/js/bootstrap-select.js
+++ b/js/bootstrap-select.js
@@ -1,6 +1,57 @@
 (function ($) {
   'use strict';
 
+  // Polyfill for browsers with no classList support
+  // Remove in v2
+  if (!('classList' in document.createElement('_'))) {
+    (function (view) {
+      if (!('Element' in view)) return;
+
+      var classListProp = 'classList',
+          protoProp = 'prototype',
+          elemCtrProto = view.Element[protoProp],
+          objCtr = Object,
+          classListGetter = function () {
+            var $elem = $(this);
+
+            return {
+              add: function (classes) {
+                return $elem.addClass(classes);
+              },
+              remove: function (classes) {
+                return $elem.removeClass(classes);
+              },
+              toggle: function (classes, force) {
+                return $elem.toggleClass(classes, force);
+              },
+              contains: function (classes) {
+                return $elem.hasClass(classes);
+              }
+            }
+          };
+
+      if (objCtr.defineProperty) {
+        var classListPropDesc = {
+          get: classListGetter,
+          enumerable: true,
+          configurable: true
+        };
+        try {
+          objCtr.defineProperty(elemCtrProto, classListProp, classListPropDesc);
+        } catch (ex) { // IE 8 doesn't support enumerable:true
+          // adding undefined to fight this issue https://github.com/eligrey/classList.js/issues/36
+          // modernie IE8-MSW7 machine has IE8 8.0.6001.18702 and is affected
+          if (ex.number === undefined || ex.number === -0x7FF5EC54) {
+            classListPropDesc.enumerable = false;
+            objCtr.defineProperty(elemCtrProto, classListProp, classListPropDesc);
+          }
+        }
+      } else if (objCtr[protoProp].__defineGetter__) {
+        elemCtrProto.__defineGetter__(classListProp, classListGetter);
+      }
+    }(window));
+  }
+
   var testElement = document.createElement('_');
 
   testElement.classList.toggle('c3', false);
@@ -19,6 +70,8 @@
     };
   }
 
+  testElement = null;
+
   // shallow array comparison
   function isEqual (array1, array2) {
     return array1.length === array2.length && array1.every(function (element, index) {