Python pdb 模块，Restart() 实例源码

def run_with_pdb(cmd, *args, **kwargs):
    # Stolen from pdb.main
    pdb_context = pdb.Pdb()
    try:
        ret = pdb_context.runcall(cmd, **kwargs)
        print("The program finished")
        return ret
    except pdb.Restart:
        print("Restarting %s with arguments: %s, %s" % (cmd.__name__, args, kwargs))
        # Yes, that's a hack
        return run_with_pdb(cmd, *args, **kwargs)
    except SystemExit:
        # In most cases SystemExit does not warrant a post-mortem session.
        print("The program exited via sys.exit(). Exit status:", end=' ')
        print(sys.exc_info()[1])
    except SyntaxError:
        traceback.print_exc()
        sys.exit(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_context.interaction(None, t)
        print("Post mortem debugger finished.")

def main():
    import traceback
    import sys
    import getopt

    try:
        from pdb import Restart
    except ImportError:
        class Restart(Exception):
            pass

    opts, args = getopt.getopt(sys.argv[1:], 'hc:', ['--help', '--command='])

    if not args:
        print(_usage)
        sys.exit(2)

    commands = []
    for opt, optarg in opts:
        if opt in ['-h', '--help']:
            print(_usage)
            sys.exit()
        elif opt in ['-c', '--command']:
            commands.append(optarg)

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

    sys.argv = args     # Hide "pdb.py" from argument list

    # 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 = _init_pdb(commands=commands)
    while 1:
        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(sys.argv[1:]))
        except SystemExit:
            # In most cases SystemExit does not warrant a post-mortem session.
            print("The program exited via sys.exit(). Exit status: ", end='')
            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")