Fix string dereference in ecma_op_create_dynamic_function (#3873)

Fixes #3862

JerryScript-DCO-1.0-Signed-off-by: Adam Szilagyi aszilagy@inf.u-szeged.hu

tests/jerry/es2015/reflect-construct.js

@@ -51,8 +51,8 @@ function DogClass () {
 
 var obj1 = Reflect.construct (CatClass, args, DogClass);
 assert (obj1.name === 'Cat');
-// assert (!(ob1 instanceof CatClass)); This is true because new target is not supported yet
-// assert (obj1 instanceof DogClass); This is false because new target is not supported yet
+assert (!(obj1 instanceof CatClass));
+assert (obj1 instanceof DogClass);
 
 try {
   Reflect.construct (func1, 5, 5);

tests/jerry/es2015/regression-test-issue-3862.js

@@ -0,0 +1,29 @@
+// Copyright JS Foundation and other contributors, http://js.foundation
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+var target = function() {};
+var handler = {
+    get() {
+        if ($);
+    }
+};
+
+var o = new Proxy(target, handler);
+
+try {
+  Reflect.construct(Function, ['c'], o);
+  assert(false);  
+} catch (e) {
+  assert(e instanceof ReferenceError);
+}