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
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:
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:
class TestHelpMetavarTypeFormatter(HelpTestCase):
- """"""
def custom_type(string):
return string
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
# ============================