node/deps/v8/test/mjsunit/regress/regress-4945.js

// Copyright 2016 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

function* g(o) {
  yield 'x' in o;
}

assertTrue(g({x: 1}).next().value);
assertFalse(g({}).next().value);