update node modules

node_modules/parse5/lib/utils/merge-options.js

@@ -3,8 +3,8 @@
 module.exports = function mergeOptions(defaults, options) {
     options = options || Object.create(null);
 
-    return [defaults, options].reduce(function (merged, optObj) {
-        Object.keys(optObj).forEach(function (key) {
+    return [defaults, options].reduce((merged, optObj) => {
+        Object.keys(optObj).forEach(key => {
             merged[key] = optObj[key];
         });
 

node_modules/parse5/lib/utils/mixin.js

@@ -1,18 +1,39 @@
 'use strict';
 
-var Mixin = module.exports = function (host) {
-    var originalMethods = {},
-        overriddenMethods = this._getOverriddenMethods(this, originalMethods);
+class Mixin {
+    constructor(host) {
+        const originalMethods = {};
+        const overriddenMethods = this._getOverriddenMethods(this, originalMethods);
 
-    Object.keys(overriddenMethods).forEach(function (key) {
-        if (typeof overriddenMethods[key] === 'function') {
-            originalMethods[key] = host[key];
-            host[key] = overriddenMethods[key];
+        for (const key of Object.keys(overriddenMethods)) {
+            if (typeof overriddenMethods[key] === 'function') {
+                originalMethods[key] = host[key];
+                host[key] = overriddenMethods[key];
+            }
         }
-    });
-};
-
-Mixin.prototype._getOverriddenMethods = function () {
-    throw new Error('Not implemented');
+    }
+
+    _getOverriddenMethods() {
+        throw new Error('Not implemented');
+    }
+}
+
+Mixin.install = function(host, Ctor, opts) {
+    if (!host.__mixins) {
+        host.__mixins = [];
+    }
+
+    for (let i = 0; i < host.__mixins.length; i++) {
+        if (host.__mixins[i].constructor === Ctor) {
+            return host.__mixins[i];
+        }
+    }
+
+    const mixin = new Ctor(host, opts);
+
+    host.__mixins.push(mixin);
+
+    return mixin;
 };
 
+module.exports = Mixin;