Add a test for empty dictionaries

Signed-off-by: mulhern <amulhern@redhat.com>

Author: mulkieran

tests/test_hypothesis.py

@@ -157,7 +157,14 @@ class ParseTestCase(unittest.TestCase):
 
     @given(
         strategies.tuples(
-            dbus_signatures(min_complete_types=1, max_complete_types=1),
+            dbus_signatures(
+                min_complete_types=1,
+                max_complete_types=1,
+                exclude_arrays=True,
+                exclude_dicts=True,
+                exclude_structs=True,
+                blacklist="v",
+            ),
             dbus_signatures(min_complete_types=1, max_complete_types=1),
         )
     )
@@ -168,7 +175,7 @@ def test_empty_dict(self, strat):
         """
         (key_sig, value_sig) = strat
         sig = f"{key_sig}{value_sig}"
-        self.assertEqual(signature(dbus.Dictionary(signature=sig)), sig)
+        self.assertEqual(signature(dbus.Dictionary(signature=sig)), "a{" + sig + "}")
 
     @given(
         dbus_signatures(