Ios 使用 Xcode 的 All Exceptions 断点时忽略某些异常

发布于10月09日

我在Xcode中配置了一个所有异常断点:

有时候Xcode会停在一行上，比如:

[managedObjectContext save:&error];

具有以下回溯:

但是，如果您单击"继续"，程序会继续运行，就好像什么都没有发生一样.

How can I ignore these "normal" exceptions, but still have the debugger stop on exceptions in my own code?个

(我知道发生这种情况是因为Core Data内部抛出和捕获异常，而Xcode只是响应我的请求，每当抛出异常时暂停程序.但是，我想忽略这些，这样我就可以继续调试我自己的代码了！)

Moderators: this is similar to 100, but I think that question takes too long to get around to the point and doesn't have any useful answers. Can they be linked?

Installation

将此脚本放入~/Library/lldb/ignore_specified_objc_exceptions.py或其他有用的位置.

import lldb
import re
import shlex

# This script allows Xcode to selectively ignore Obj-C exceptions
# based on any selector on the NSException instance

def getRegister(target):
    if target.triple.startswith('x86_64'):
        return "rdi"
    elif target.triple.startswith('i386'):
        return "eax"
    elif target.triple.startswith('arm64'):
        return "x0"
    else:
        return "r0"

def callMethodOnException(frame, register, method):
    return frame.EvaluateExpression("(NSString *)[(NSException *)${0} {1}]".format(register, method)).GetObjectDescription()

def filterException(debugger, user_input, result, unused):
    target = debugger.GetSelectedTarget()
    frame = target.GetProcess().GetSelectedThread().GetFrameAtIndex(0)

    if frame.symbol.name != 'objc_exception_throw':
        # We can't handle anything except objc_exception_throw
        return None

    filters = shlex.split(user_input)

    register = getRegister(target)


    for filter in filters:
        method, regexp_str = filter.split(":", 1)
        value = callMethodOnException(frame, register, method)

        if value is None:
            output = "Unable to grab exception from register {0} with method {1}; skipping...".format(register, method)
            result.PutCString(output)
            result.flush()
            continue

        regexp = re.compile(regexp_str)

        if regexp.match(value):
            output = "Skipping exception because exception's {0} ({1}) matches {2}".format(method, value, regexp_str)
            result.PutCString(output)
            result.flush()

            # If we tell the debugger to continue before this script finishes,
            # Xcode gets into a weird state where it won't refuse to quit LLDB,
            # so we set async so the script terminates and hands control back to Xcode
            debugger.SetAsync(True)
            debugger.HandleCommand("continue")
            return None

    return None

def __lldb_init_module(debugger, unused):
    debugger.HandleCommand('command script add --function ignore_specified_objc_exceptions.filterException ignore_specified_objc_exceptions')

将以下内容添加到~/.lldbinit:

command script import ~/Library/lldb/ignore_specified_objc_exceptions.py个

如果您将~/Library/lldb/ignore_specified_objc_exceptions.py保存在其他位置，请将其替换为正确的路径.