|  | // 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. | 
|  |  | 
|  | // Flags: --opt | 
|  |  | 
|  | Debug = debug.Debug | 
|  |  | 
|  | var exception = null; | 
|  |  | 
|  | function f() { | 
|  | let a = 0; | 
|  | function g() { | 
|  | let a = 1; | 
|  | { | 
|  | let a = 2; | 
|  | debugger;  // Breakpoint. | 
|  | if (a !== 3) { | 
|  | // We cannot change stack locals in optimized frames. | 
|  | assertEquals(2, a); | 
|  | assertOptimized(g); | 
|  | } | 
|  | } | 
|  | assertEquals(1, a); | 
|  | } | 
|  | g.call(1); | 
|  | if (a !== 4) { | 
|  | // We cannot change stack locals in optimized frames. | 
|  | assertEquals(0, a); | 
|  | assertOptimized(f); | 
|  | } | 
|  | } | 
|  |  | 
|  |  | 
|  | function listener(event, exec_state, event_data, data) { | 
|  | if (event != Debug.DebugEvent.Break) return; | 
|  | try { | 
|  | exec_state.frame(0).evaluate("a = 3"); | 
|  | exec_state.frame(1).evaluate("a = 4"); | 
|  | assertThrows(() => exec_state.frame(0).evaluate("this = 2")); | 
|  | } catch (e) { | 
|  | exception = e; | 
|  | print("Caught something. " + e + " " + e.stack); | 
|  | }; | 
|  | }; | 
|  |  | 
|  | Debug.setListener(listener); | 
|  |  | 
|  | f(); | 
|  |  | 
|  | Debug.setListener(null); | 
|  | assertNull(exception); |