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[yaffs-website] / node_modules / core-js / modules / es6.reflect.construct.js

diff --git a/node_modules/core-js/modules/es6.reflect.construct.js b/node_modules/core-js/modules/es6.reflect.construct.js
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+// 26.1.2 Reflect.construct(target, argumentsList [, newTarget])
+var $export    = require('./_export')
+  , create     = require('./_object-create')
+  , aFunction  = require('./_a-function')
+  , anObject   = require('./_an-object')
+  , isObject   = require('./_is-object')
+  , fails      = require('./_fails')
+  , bind       = require('./_bind')
+  , rConstruct = (require('./_global').Reflect || {}).construct;
+
+// MS Edge supports only 2 arguments and argumentsList argument is optional
+// FF Nightly sets third argument as `new.target`, but does not create `this` from it
+var NEW_TARGET_BUG = fails(function(){
+  function F(){}
+  return !(rConstruct(function(){}, [], F) instanceof F);
+});
+var ARGS_BUG = !fails(function(){
+  rConstruct(function(){});
+});
+
+$export($export.S + $export.F * (NEW_TARGET_BUG || ARGS_BUG), 'Reflect', {
+  construct: function construct(Target, args /*, newTarget*/){
+    aFunction(Target);
+    anObject(args);
+    var newTarget = arguments.length < 3 ? Target : aFunction(arguments[2]);
+    if(ARGS_BUG && !NEW_TARGET_BUG)return rConstruct(Target, args, newTarget);
+    if(Target == newTarget){
+      // w/o altered newTarget, optimization for 0-4 arguments
+      switch(args.length){
+        case 0: return new Target;
+        case 1: return new Target(args[0]);
+        case 2: return new Target(args[0], args[1]);
+        case 3: return new Target(args[0], args[1], args[2]);
+        case 4: return new Target(args[0], args[1], args[2], args[3]);
+      }
+      // w/o altered newTarget, lot of arguments case
+      var $args = [null];
+      $args.push.apply($args, args);
+      return new (bind.apply(Target, $args));
+    }
+    // with altered newTarget, not support built-in constructors
+    var proto    = newTarget.prototype
+      , instance = create(isObject(proto) ? proto : Object.prototype)
+      , result   = Function.apply.call(Target, instance, args);
+    return isObject(result) ? result : instance;
+  }
+});
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