|  | // 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. | 
|  |  | 
|  |  | 
|  | var Debug = debug.Debug; | 
|  | var exception = null; | 
|  |  | 
|  | function listener(event, exec_state, event_data, data) { | 
|  | if (event != Debug.DebugEvent.Break) return; | 
|  | try { | 
|  | assertThrows(() => exec_state.frame(0).evaluate("bar.baz"), ReferenceError); | 
|  | } catch (e) { | 
|  | exception = e; | 
|  | } | 
|  | } | 
|  |  | 
|  | Debug.setListener(listener); | 
|  |  | 
|  | (function() { | 
|  | debugger;    // bar is still in TDZ at this point. | 
|  | let bar = 1; | 
|  | (x => bar);  // force bar to be context-allocated. | 
|  | })(); | 
|  |  | 
|  | Debug.setListener(null); | 
|  | assertNull(exception); |