fix: update isFunction (#20912)

src/utils/types.js

@@ -1,3 +1,5 @@
+import Vue from 'vue';
+
 export function isString(obj) {
   return Object.prototype.toString.call(obj) === '[object String]';
 }
@@ -10,11 +12,25 @@ export function isHtmlElement(node) {
   return node && node.nodeType === Node.ELEMENT_NODE;
 }
 
-export const isFunction = (functionToCheck) => {
+/**
+ *  - Inspired:
+ *    https://github.com/jashkenas/underscore/blob/master/modules/isFunction.js
+ */
+let isFunction = (functionToCheck) => {
   var getType = {};
   return functionToCheck && getType.toString.call(functionToCheck) === '[object Function]';
 };
 
+if (typeof /./ !== 'function' && typeof Int8Array !== 'object' && (Vue.prototype.$isServer || typeof document.childNodes !== 'function')) {
+  isFunction = function(obj) {
+    return typeof obj === 'function' || false;
+  };
+}
+
+export {
+  isFunction
+};
+
 export const isUndefined = (val)=> {
   return val === void 0;
 };