diff options
| -rw-r--r-- | Lib/argparse.py | 9 | ||||
| -rw-r--r-- | Lib/test/test_argparse.py | 30 | ||||
| -rw-r--r-- | Misc/ACKS | 1 | ||||
| -rw-r--r-- | Misc/NEWS.d/next/Library/2019-07-19-01-46-56.bpo-16970.GEASf5.rst | 2 |
4 files changed, 38 insertions, 4 deletions
diff --git a/Lib/argparse.py b/Lib/argparse.py index e45b67b..a300828 100644 --- a/Lib/argparse.py +++ b/Lib/argparse.py @@ -593,7 +593,10 @@ class HelpFormatter(object): elif action.nargs == SUPPRESS: result = '' else: - formats = ['%s' for _ in range(action.nargs)] + try: + formats = ['%s' for _ in range(action.nargs)] + except TypeError: + raise ValueError("invalid nargs value") from None result = ' '.join(formats) % get_metavar(action.nargs) return result @@ -850,7 +853,7 @@ class _StoreAction(Action): help=None, metavar=None): if nargs == 0: - raise ValueError('nargs for store actions must be > 0; if you ' + raise ValueError('nargs for store actions must be != 0; if you ' 'have nothing to store, actions such as store ' 'true or store const may be more appropriate') if const is not None and nargs != OPTIONAL: @@ -942,7 +945,7 @@ class _AppendAction(Action): help=None, metavar=None): if nargs == 0: - raise ValueError('nargs for append actions must be > 0; if arg ' + raise ValueError('nargs for append actions must be != 0; if arg ' 'strings are not supplying the value to append, ' 'the append const action may be more appropriate') if const is not None and nargs != OPTIONAL: diff --git a/Lib/test/test_argparse.py b/Lib/test/test_argparse.py index 5128dc5..d6d1609 100644 --- a/Lib/test/test_argparse.py +++ b/Lib/test/test_argparse.py @@ -4263,7 +4263,6 @@ class TestHelpSubparsersWithHelpOrdering(HelpTestCase): class TestHelpMetavarTypeFormatter(HelpTestCase): - """""" def custom_type(string): return string @@ -5150,6 +5149,35 @@ class TestAddArgumentMetavar(TestCase): def test_nargs_3_metavar_length3(self): self.do_test_no_exception(nargs=3, metavar=("1", "2", "3")) + +class TestInvalidNargs(TestCase): + + EXPECTED_INVALID_MESSAGE = "invalid nargs value" + EXPECTED_RANGE_MESSAGE = ("nargs for store actions must be != 0; if you " + "have nothing to store, actions such as store " + "true or store const may be more appropriate") + + def do_test_range_exception(self, nargs): + parser = argparse.ArgumentParser() + with self.assertRaises(ValueError) as cm: + parser.add_argument("--foo", nargs=nargs) + self.assertEqual(cm.exception.args[0], self.EXPECTED_RANGE_MESSAGE) + + def do_test_invalid_exception(self, nargs): + parser = argparse.ArgumentParser() + with self.assertRaises(ValueError) as cm: + parser.add_argument("--foo", nargs=nargs) + self.assertEqual(cm.exception.args[0], self.EXPECTED_INVALID_MESSAGE) + + # Unit tests for different values of nargs + + def test_nargs_alphabetic(self): + self.do_test_invalid_exception(nargs='a') + self.do_test_invalid_exception(nargs="abcd") + + def test_nargs_zero(self): + self.do_test_range_exception(nargs=0) + # ============================ # from argparse import * tests # ============================ @@ -1878,3 +1878,4 @@ Edison Abahurire Geoff Shannon Batuhan Taskaya Aleksandr Balezin +Robert Leenders diff --git a/Misc/NEWS.d/next/Library/2019-07-19-01-46-56.bpo-16970.GEASf5.rst b/Misc/NEWS.d/next/Library/2019-07-19-01-46-56.bpo-16970.GEASf5.rst new file mode 100644 index 0000000..7285b81 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2019-07-19-01-46-56.bpo-16970.GEASf5.rst @@ -0,0 +1,2 @@ +Adding a value error when an invalid value in passed to nargs +Patch by Robert Leenders |