src/v8/test/mjsunit/regress/regress-5845.js - cobalt - Git at Google

 // Copyright 2017 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.

 assertDoesNotThrow('/(?:(?=(foo)))?/u.exec("foo")');
 assertThrows('/(?=(foo))?/u.exec("foo")');
	// Copyright 2017 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.

	assertDoesNotThrow('/(?:(?=(foo)))?/u.exec("foo")');
	assertThrows('/(?=(foo))?/u.exec("foo")');