regress-1081309.js

Google浏览器V8内核代码

// Copyright 2008 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
//       notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
//       copyright notice, this list of conditions and the following
//       disclaimer in the documentation and/or other materials provided
//       with the distribution.
//     * Neither the name of Google Inc. nor the names of its
//       contributors may be used to endorse or promote products derived
//       from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

// Flags: --expose-debug-as debug
// Get the Debug object exposed from the debug context global object.
Debug = debug.Debug

// Make sure that the backtrace command can be processed when the receiver is
// undefined.
listenerCalled = false;
exception = false;

function safeEval(code) {
  try {
    return eval('(' + code + ')');
  } catch (e) {
    return undefined;
  }
}

function listener(event, exec_state, event_data, data) {
  try {
  if (event == Debug.DebugEvent.Exception)
  {
    // The expected backtrace is
    // 1: g
    // 0: [anonymous]
    
    // Get the debug command processor.
    var dcp = exec_state.debugCommandProcessor();

    // Get the backtrace.
    var json;
    json = '{"seq":0,"type":"request","command":"backtrace"}'
    var backtrace = safeEval(dcp.processDebugJSONRequest(json)).body;
    assertEquals(2, backtrace.totalFrames);
    assertEquals(2, backtrace.frames.length);

    assertEquals("g", backtrace.frames[0].func.name);
    assertEquals("", backtrace.frames[1].func.name);

    listenerCalled = true;
  }
  } catch (e) {
    exception = e
  };
};

// Add the debug event listener.
Debug.addListener(listener);

// Call method on undefined.
function g() {
  (void 0).f();
};

// Break on the exception to do a backtrace with undefined as receiver.
Debug.setBreakOnException(true);
try {
  g();
} catch(e) {
  // Ignore the exception "Cannot call method 'x' of undefined"
}

// Make sure that the debug event listener vas invoked.
assertTrue(listenerCalled, "listener not called");
assertFalse(exception, "exception in listener", exception)