diff --git a/Lib/pdb.py b/Lib/pdb.py index 14ed25ed147011..fa5b14ccb9271b 100644 --- a/Lib/pdb.py +++ b/Lib/pdb.py @@ -3543,7 +3543,15 @@ def exit_with_permission_help_text(): sys.exit(1) -def main(): +def parse_args(): + # We want pdb to be as intuitive as possible to users, so we need to do some + # heuristic parsing to deal with ambiguity. + # For example: + # "python -m pdb -m foo -p 1" should pass "-p 1" to "foo". + # "python -m pdb foo.py -m bar" should pass "-m bar" to "foo.py". + # "python -m pdb -m foo -m bar" should pass "-m bar" to "foo". + # This require some customized parsing logic to find the actual debug target. + import argparse parser = argparse.ArgumentParser( @@ -3554,58 +3562,57 @@ def main(): color=True, ) - # We need to maunally get the script from args, because the first positional - # arguments could be either the script we need to debug, or the argument - # to the -m module + # Get all the commands out first. For backwards compatibility, we allow + # -c commands to be after the target. parser.add_argument('-c', '--command', action='append', default=[], metavar='command', dest='commands', help='pdb commands to execute as if given in a .pdbrc file') - parser.add_argument('-m', metavar='module', dest='module') - parser.add_argument('-p', '--pid', type=int, help="attach to the specified PID", default=None) - if len(sys.argv) == 1: + opts, args = parser.parse_known_args() + + if not args: # If no arguments were given (python -m pdb), print the whole help message. # Without this check, argparse would only complain about missing required arguments. + # We need to add the arguments definitions here to get a proper help message. + parser.add_argument('-m', metavar='module', dest='module') + parser.add_argument('-p', '--pid', type=int, help="attach to the specified PID", default=None) parser.print_help() sys.exit(2) + elif args[0] == '-p' or args[0] == '--pid': + # Attach to a pid + parser.add_argument('-p', '--pid', type=int, help="attach to the specified PID", default=None) + opts, args = parser.parse_known_args() + if args: + # For --pid, any extra arguments are invalid. + parser.error(f"unrecognized arguments: {' '.join(args)}") + elif args[0] == '-m': + # Debug a module, we only need the first -m module argument. + # The rest is passed to the module itself. + parser.add_argument('-m', metavar='module', dest='module') + opt_module = parser.parse_args(args[:2]) + opts.module = opt_module.module + args = args[2:] + elif args[0].startswith('-'): + # Invalid argument before the script name. + invalid_args = list(itertools.takewhile(lambda a: a.startswith('-'), args)) + parser.error(f"unrecognized arguments: {' '.join(invalid_args)}") - opts, args = parser.parse_known_args() + # Otherwise it's debugging a script and we already parsed all -c commands. + + return opts, args - if opts.pid: - # If attaching to a remote pid, unrecognized arguments are not allowed. - # This will raise an error if there are extra unrecognized arguments. - opts = parser.parse_args() - if opts.module: - parser.error("argument -m: not allowed with argument --pid") +def main(): + opts, args = parse_args() + + if getattr(opts, 'pid', None) is not None: try: attach(opts.pid, opts.commands) except PermissionError as e: exit_with_permission_help_text() return - elif opts.module: - # If a module is being debugged, we consider the arguments after "-m module" to - # be potential arguments to the module itself. We need to parse the arguments - # before "-m" to check if there is any invalid argument. - # e.g. "python -m pdb -m foo --spam" means passing "--spam" to "foo" - # "python -m pdb --spam -m foo" means passing "--spam" to "pdb" and is invalid - idx = sys.argv.index('-m') - args_to_pdb = sys.argv[1:idx] - # This will raise an error if there are invalid arguments - parser.parse_args(args_to_pdb) - else: - # If a script is being debugged, then pdb expects the script name as the first argument. - # Anything before the script is considered an argument to pdb itself, which would - # be invalid because it's not parsed by argparse. - invalid_args = list(itertools.takewhile(lambda a: a.startswith('-'), args)) - if invalid_args: - parser.error(f"unrecognized arguments: {' '.join(invalid_args)}") - sys.exit(2) - - if opts.module: + elif getattr(opts, 'module', None) is not None: file = opts.module target = _ModuleTarget(file) else: - if not args: - parser.error("no module or script to run") file = args.pop(0) if file.endswith('.pyz'): target = _ZipTarget(file) diff --git a/Lib/test/test_pdb.py b/Lib/test/test_pdb.py index 9a7d855003551a..2ca689e0adf710 100644 --- a/Lib/test/test_pdb.py +++ b/Lib/test/test_pdb.py @@ -3974,7 +3974,10 @@ def test_run_module_with_args(self): commands = """ continue """ - self._run_pdb(["calendar", "-m"], commands, expected_returncode=2) + self._run_pdb(["calendar", "-m"], commands, expected_returncode=1) + + _, stderr = self._run_pdb(["-m", "calendar", "-p", "1"], commands) + self.assertIn("unrecognized arguments: -p", stderr) stdout, _ = self._run_pdb(["-m", "calendar", "1"], commands) self.assertIn("December", stdout) diff --git a/Misc/NEWS.d/next/Library/2025-11-03-05-38-31.gh-issue-125115.jGS8MN.rst b/Misc/NEWS.d/next/Library/2025-11-03-05-38-31.gh-issue-125115.jGS8MN.rst new file mode 100644 index 00000000000000..d36debec3ed6cc --- /dev/null +++ b/Misc/NEWS.d/next/Library/2025-11-03-05-38-31.gh-issue-125115.jGS8MN.rst @@ -0,0 +1 @@ +Refactor the :mod:`pdb` parsing issue so positional arguments can pass through intuitively.