diff options
| -rw-r--r-- | Lib/argparse.py | 21 | ||||
| -rw-r--r-- | Lib/test/test_argparse.py | 48 | ||||
| -rw-r--r-- | Misc/ACKS | 1 | ||||
| -rw-r--r-- | Misc/NEWS | 6 |
4 files changed, 69 insertions, 7 deletions
diff --git a/Lib/argparse.py b/Lib/argparse.py index 0ee8c08..f77c0c2 100644 --- a/Lib/argparse.py +++ b/Lib/argparse.py @@ -1714,10 +1714,7 @@ class ArgumentParser(_AttributeHolder, _ActionsContainer): if action.dest is not SUPPRESS: if not hasattr(namespace, action.dest): if action.default is not SUPPRESS: - default = action.default - if isinstance(action.default, str): - default = self._get_value(action, default) - setattr(namespace, action.dest, default) + setattr(namespace, action.dest, action.default) # add any parser defaults that aren't present for dest in self._defaults: @@ -1945,12 +1942,22 @@ class ArgumentParser(_AttributeHolder, _ActionsContainer): if positionals: self.error(_('too few arguments')) - # make sure all required actions were present + # make sure all required actions were present, and convert defaults. for action in self._actions: - if action.required: - if action not in seen_actions: + if action not in seen_actions: + if action.required: name = _get_action_name(action) self.error(_('argument %s is required') % name) + else: + # Convert action default now instead of doing it before + # parsing arguments to avoid calling convert functions + # twice (which may fail) if the argument was given, but + # only if it was defined already in the namespace + if (action.default is not None and + hasattr(namespace, action.dest) and + action.default is getattr(namespace, action.dest)): + setattr(namespace, action.dest, + self._get_value(action, action.default)) # make sure all required groups had one option present for group in self._mutually_exclusive_groups: diff --git a/Lib/test/test_argparse.py b/Lib/test/test_argparse.py index 3a29761..cc05160 100644 --- a/Lib/test/test_argparse.py +++ b/Lib/test/test_argparse.py @@ -1462,6 +1462,22 @@ class TestFileTypeR(TempDirMixin, ParserTestCase): ('readonly', NS(x=None, spam=RFile('readonly'))), ] +class TestFileTypeDefaults(TempDirMixin, ParserTestCase): + """Test that a file is not created unless the default is needed""" + def setUp(self): + super(TestFileTypeDefaults, self).setUp() + file = open(os.path.join(self.temp_dir, 'good'), 'w') + file.write('good') + file.close() + + argument_signatures = [ + Sig('-c', type=argparse.FileType('r'), default='no-file.txt'), + ] + # should provoke no such file error + failures = [''] + # should not provoke error because default file is created + successes = [('-c good', NS(c=RFile('good')))] + class TestFileTypeRB(TempDirMixin, ParserTestCase): """Test the FileType option/argument type for reading files""" @@ -4468,6 +4484,38 @@ class TestArgumentTypeError(TestCase): else: self.fail() +# ================================================ +# Check that the type function is called only once +# ================================================ + +class TestTypeFunctionCallOnlyOnce(TestCase): + + def test_type_function_call_only_once(self): + def spam(string_to_convert): + self.assertEqual(string_to_convert, 'spam!') + return 'foo_converted' + + parser = argparse.ArgumentParser() + parser.add_argument('--foo', type=spam, default='bar') + args = parser.parse_args('--foo spam!'.split()) + self.assertEqual(NS(foo='foo_converted'), args) + +# ================================================================ +# Check that the type function is called with a non-string default +# ================================================================ + +class TestTypeFunctionCallWithNonStringDefault(TestCase): + + def test_type_function_call_with_non_string_default(self): + def spam(int_to_convert): + self.assertEqual(int_to_convert, 0) + return 'foo_converted' + + parser = argparse.ArgumentParser() + parser.add_argument('--foo', type=spam, default=0) + args = parser.parse_args([]) + self.assertEqual(NS(foo='foo_converted'), args) + # ====================== # parse_known_args tests # ====================== @@ -305,6 +305,7 @@ Nils Fischbeck Frederik Fix Matt Fleming Hernán Martínez Foffani +Arnaud Fontaine Michael Foord Amaury Forgeot d'Arc Doug Fort @@ -112,6 +112,12 @@ Core and Builtins Library ------- +- Issue #12776,#11839: call argparse type function (specified by add_argument) + only once. Before, the type function was called twice in the case where the + default was specified and the argument was given as well. This was + especially problematic for the FileType type, as a default file would always + be opened, even if a file argument was specified on the command line. + - Issue #13370: Ensure that ctypes works on Mac OS X when Python is compiled using the clang compiler |