dbgr.py

import sys
import os
from pdb import Pdb

banner = """Usage:
%(command)s @<module>:<linenumber> ... <filename> <args>

Use @<module>:<linenumber> to set one or multiple breakpoints.
<module> may be an absolute path to a module file, or relative to sys.path.

Example:
%(command)s @mypackage/mymodule.py:42 myscript.py --some-argument

"""

def parse_args(args):
    breakpoints = map(lambda a: a[1:], filter(lambda a: a.startswith('@'), args))
    other = filter(lambda a: not a.startswith('@'), args)
    return breakpoints, other

def main():
    breakpoints, original_args = parse_args(sys.argv[1:])

    if not original_args or sys.argv[1] in ("--help", "-h"):
        sys.stderr.write(banner % {'command': sys.argv[0]})
        sys.exit(2)

    # Replace sys.argv so the script only sees the intended arguments.
    sys.argv = original_args

    mainpyfile =  original_args[0]     # Get script filename
    if not os.path.exists(mainpyfile):
        print 'Error:', mainpyfile, 'does not exist'
        sys.exit(1)

    # Replace pdb's dir with script's dir in front of module search path.
    sys.path[0] = os.path.dirname(mainpyfile)

    # Note on saving/restoring sys.argv: it's a good idea when sys.argv was
    # modified by the script being debugged. It's a bad idea when it was
    # changed by the user from the command line. There is a "restart" command
    # which allows explicit specification of command line arguments.
    pdb = Pdb()
    while True:
        for bp in breakpoints:
            pdb.do_break(bp)

        try:
            pdb._runscript(mainpyfile)
            if pdb._user_requested_quit:
                break
            print "The program finished and will be restarted"
        except Restart:
            print "Restarting", mainpyfile, "with arguments:"
            print "\t" + " ".join(original_args[1:])
        except SystemExit:
            # In most cases SystemExit does not warrant a post-mortem session.
            print "The program exited via sys.exit(). Exit status: ",
            print sys.exc_info()[1]
        except:
            traceback.print_exc()
            print "Uncaught exception. Entering post mortem debugging"
            print "Running 'cont' or 'step' will restart the program"
            t = sys.exc_info()[2]
            pdb.interaction(None, t)
            print "Post mortem debugger finished. The " + mainpyfile + \
                  " will be restarted"


if __name__ == '__main__':
    main()