set breakpoint in another module/file

[Daniel]

Is there a way with pdb to set a breakpoint in another module directly
using a command similar to set_trace() ? For example, I'd like to do
something like this in my source code:

import pdb
pdb.setbreak(42, "/path/to/universe.py", "name == 'hitchhiker'")

Is there a way to do (something like) that with the pdb that ships
with Python? If not, what would people think of adding an additional
function to the pdb module that would do something like the following
code (see below). My use case for this is that often I'd like to set a
breakpoint in some module that does not belong to the project I'm
working in. I rather not edit the module, which is often in site-
packages. The workaround of course is to use set_trace() to drop into
pdb and then set the breakpoint at the pdb prompt, but that's clumsy.
I've found this to be handy:


def setbreak(line=None, file=None, cond=None, temp=0, frame=None,
throw=False):
"""set a breakpoint or a given line in file with conditional

arguments:
line - line number on which to break
file - module or filename where the breakpoint should be set
cond - string with conditional expression, which (if given)
must
evaluate to true to break
temp - if true, create a temporary breakpoint

example usage:

setbreak(42, "/path/to/universe.py", "name == 'hitchhiker'")

"""
if frame is None:
frame = sys._getframe().f_back
if file is None:
file = frame.f_code.co_filename
elif not file.startswith("file:") and os.path.sep not in file:
try:
mod = __import__(file[4:], globals(), locals(),
["__file__"])
except ImportError, err:
if throw:
raise
sys.__stdout__.write("cannot set breakpoint: %s:%s : %s" %
(file, line, err))
return
file = mod.__file__
sys.__stdout__.write("breaking in: %s" % file)
if file.endswith(".pyc"):
file = file[:-1]
pdb = Pdb(stdout=sys.__stdout__) # use sys.__stdout__ to work with
nose tests
pdb.reset()
pdb.curframe = frame
pdb.botframe = object()
pdb.set_continue()
temp = line
while temp < line + 10:
error = pdb.set_break(file, temp, cond=cond, temporary=temp)
if error:
temp += 1
else:
break
if error:
error = pdb.set_break(file, line, cond=cond, temporary=temp)
if throw:
raise Error(error)
sys.__stdout__.write("\n%s\n" % error)
return
sys.__stdout__.write("\n")
pdb.do_break("") # print breakpoints
sys.settrace(pdb.trace_dispatch)


I'm sure there is a better way to implement some of this, especially
the part marked with HACK, but it seems to work for me in most
situations.

~ Daniel

 

[Stef Mientki]

Is there a way with pdb to set a breakpoint in another module directly
using a command similar to set_trace() ? For example, I'd like to do
something like this in my source code:

import pdb
pdb.setbreak(42, "/path/to/universe.py", "name == 'hitchhiker'")

I think winpdb ( nothing todo with windows-OS ) can do that and much more.

cheers,
Stef

 

[millerdev]

I think winpdb ( nothing todo with windows-OS ) can do that and much more.

The problem with winpdb (which I played with a long time ago) is that
it's much heavier than the built-in pdb--it's a GUI debugger. It
requires the beast called wx, which I do not use for web (or GUI)
development. I'm don't relish the thought of installing wx just for a
debugger. I'm really just looking for a simple function in the pdb
module that sets a breakpoint (which can subsequently be removed).
Nothing more.

~ Daniel