Chisel is a collection of LLDB commands to assist debugging iOS apps.
Chiselis a collection of
LLDBcommands to assist in the debugging of iOS apps.
brew update brew install chisel
.lldbinitfile doesn't exist you can create it & open it by tapping on the terminal
touch .lldbinit open .lldbinit
Then add the following line to your
# ~/.lldbinit ... command script import /usr/local/opt/chisel/libexec/fbchisellldb.py
Alternatively, download chisel and add the following line to your ~/.lldbinit file.
# ~/.lldbinit ... command script import /path/to/fbchisellldb.py
The commands will be available the next time
There are many commands; here's a few: (Compatibility with iOS/Mac indicated at right)
|Command |Description |iOS |OS X | |-----------------|----------------|-------|-------| |pviews |Print the recursive view description for the key window.|Yes|Yes| |pvc |Print the recursive view controller description for the key window.|Yes|No| |visualize |Open a
NSData(of an image),
CGColorRefin Preview.app on your Mac.|Yes|No| |fv |Find a view in the hierarchy whose class name matches the provided regex.|Yes|No| |fvc |Find a view controller in the hierarchy whose class name matches the provided regex.|Yes|No| |show/hide |Show or hide the given view or layer. You don't even have to continue the process to see the changes!|Yes|Yes| |mask/unmask |Overlay a view or layer with a transparent rectangle to visualize where it is.|Yes|No| |border/unborder |Add a border to a view or layer to visualize where it is.|Yes|Yes| |caflush |Flush the render server (equivalent to a "repaint" if no animations are in-flight).|Yes|Yes| |bmessage |Set a symbolic breakpoint on the method of a class or the method of an instance without worrying which class in the hierarchy actually implements the method.|Yes|Yes| |wivar |Set a watchpoint on an instance variable of an object.|Yes|Yes| |presponder |Print the responder chain starting from the given object.|Yes|Yes| |... |... and many more!|
To see the list of all of the commands execute the help command in
LLDBor go to the Wiki.
(lldb) help The following is a list of built-in, permanent debugger commands: ...
The following is a list of your current user-defined commands: ...
The bottom list contains all the commands sourced from
You can also inspect a specific command by passing its name as an argument to the help command (as with all other
(lldb) help border Draws a border around . Color and width can be optionally provided.
Arguments: ; Type: UIView*; The view to border.
Options: --color/-c ; Type: string; A color name such as 'red', 'green', 'magenta', etc. --width/-w ; Type: CGFloat; Desired width of border.
Syntax: border [--color=color] [--width=width]
All of the commands provided by
Chiselcome with verbose help. Be sure to read it when in doubt!
You can add local, custom commands. Here's a contrived example.
#!/usr/bin/python # Example file with custom commands, located at /magical/commands/example.py
import lldb import fbchisellldbbase as fb
def lldbcommands(): return [ PrintKeyWindowLevel() ]
class PrintKeyWindowLevel(fb.FBCommand): def name(self): return 'pkeywinlevel'
def description(self): return 'An incredibly contrived command that prints the window level of the key window.'
def run(self, arguments, options): # It's a good habit to explicitly cast the type of all return # values and arguments. LLDB can't always find them on its own. lldb.debugger.HandleCommand('p (CGFloat)[(id)[(id)[UIApplication sharedApplication] keyWindow] windowLevel]')
Then all that's left is to source the commands in lldbinit.
Chiselhas a python function just for this, loadCommandsInDirectory in the fbobjclldb.py module.
# ~/.lldbinit ... command script import /path/to/fbobjclldb.py script fbobjclldb.loadCommandsInDirectory('/magical/commands/')
There's also builtin support to make it super easy to specify the arguments and options that a command takes. See the border and pinvocation commands for example use.
Developing commands, whether for local use or contributing to
Chiseldirectly, both follow the same workflow. Create a command as described in the Custom Commands section and then
Xcode's debug bar or
process interruptif attached directly)
command source ~/.lldbinitin LLDB to source the commands
Please contribute any generic commands that you make. If it helps you then it will likely help many others! :D See
CONTRIBUTING.mdto learn how to contribute.
Chiselis MIT-licensed. See