[Lldb-commits] [PATCH] D117165: [lldb] Add long help to `crashlog`

[Dave Lee via Phabricator via lldb-commits]

kastiglione added inline comments.


================
Comment at: lldb/examples/python/crashlog.py:1236-1240
+def __lldb_init_module(debugger, internal_dict):
+    debugger.HandleCommand(
+        'command script add -c lldb.macosx.crashlog.Symbolicate crashlog')
+    debugger.HandleCommand(
         'command script add -f lldb.macosx.crashlog.save_crashlog save_crashlog')
----------------
jingham wrote:
> kastiglione wrote:
> > Note that I introduced `__lldb_init_module` here because there's some bug when registering a command class using `lldb.debugger`. In other words, this failed:
> > 
> > ```
> > lldb.debugger.HandleCommand('command script add -c mod.Command cmd')
> > ```
> > 
> > and this succeeds:
> > 
> > ```
> > def __lldb_init_module(debugger, _):
> >     debugger.HandleCommand('command script add -c mod.Command cmd')    
> > ```
> > 
> > When using the first form, an error would happen when running the command. The error message is "no function to execute".
> That makes sense.  All of the "lldb.{debugger, target, process, thread, etc}" variables are only set when entering the interactive script interpreter.  They don't get set when processing "command script import".  So lldb.debugger would have been None here.
> 
> In general, since pretty much no python we write in the lldb project is going to run in the interactive interpreter, you should never use those lldb.etc variables.
> 
> I actually think we could make the lldb.debugger work, since that really is a singleton for the command interpreter, but it seems much better form to pass debugger directly to whoever needs it, so for the sake of clarity they all get unset when we leave the interactive script interpreter.
Yes I've come to learn to avoid "lldb.{debugger, target, process, thread, etc}" at all costs, which is how I was able to get past the strange error message.

> So `lldb.debugger` would have been None here.

It wasn't, which made things trickier to understand.

Also note that the docs recommend this idiom used here in crashlog.py. Look for `if __name__ == '__main__'` in https://lldb.llvm.org/use/python-reference.html#create-a-new-lldb-command-using-a-python-function.



Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D117165/new/

https://reviews.llvm.org/D117165