feat: support new.target for function

src/evaluate.ts

@@ -893,6 +893,13 @@ const visitors: EvaluateMap = {
         }
       }
       funcScope.const("this", this);
+      // support new.target
+      funcScope.const("new", {
+        target:
+          this && this.__proto__ && this.__proto__.constructor
+            ? this.__proto__.constructor
+            : undefined
+      });
       funcScope.const("arguments", arguments);
       funcScope.isolated = false;
 
@@ -1471,7 +1478,8 @@ const visitors: EvaluateMap = {
     return func(templateObject, ...expressionResultList);
   },
   MetaProperty(path) {
-    //
+    const obj = evaluate(path.createChild(path.node.meta));
+    return obj[path.node.property.name];
   },
   AwaitExpression(path) {
     const { next } = path.ctx;

test/ecma5/function/new.target.test.ts

@@ -0,0 +1,40 @@
+import test from "ava";
+import vm from "../../../src/vm";
+
+test("new target without new", t => {
+  const sandbox: any = vm.createContext({});
+
+  const Person = vm.runInContext(
+    `
+function Person(name){
+  return new.target;
+}
+
+module.exports = Person;
+  `,
+    sandbox
+  );
+
+  t.deepEqual(Person(), undefined);
+});
+
+test("new target with new", t => {
+  const sandbox: any = vm.createContext({});
+
+  const { Person, target } = vm.runInContext(
+    `
+var target;
+
+function Person(name){
+  target = new.target;
+}
+
+new Person();
+
+module.exports = {target: target, Person: Person};
+  `,
+    sandbox
+  );
+
+  t.true(target === Person);
+});