Fixed bug in dashed arguments

Author: martinjm97

tap/tap.py

@@ -255,7 +255,7 @@ def add_argument(self, *name_or_flags, **kwargs) -> None:
                              'Arguments must be added either as class variables or by overriding '
                              'configure and including a self.add_argument call there.')
 
-        variable = get_argument_name(*name_or_flags)
+        variable = get_argument_name(*name_or_flags).replace('-', '_')
         self.argument_buffer[variable] = (name_or_flags, kwargs)
 
     def _add_arguments(self) -> None:

tests/test_integration.py

@@ -671,6 +671,16 @@ class DashedArgumentTap(Tap):
         self.assertEqual(args.arg_u_ment, 12)
         self.assertEqual(args.arg_you_mean_, 13)
 
+    def test_mismatch_dash_underscore_config_vs_annotations(self) -> None:
+        class MismatchTap(Tap):
+            arg_arg_arg: int
+
+            def configure(self):
+                self.add_argument('--arg-arg_arg', '-arg', type=str)
+
+        args = MismatchTap(underscores_to_dashes=True).parse_args('--arg-arg-arg aarg'.split())
+        self.assertEqual(args.arg_arg_arg, 'aarg')
+
 
 class ParseExplicitBoolArgsTests(TestCase):