fix(spy): handle properties that return primitive types (#132)

Author: mcous

decoy/spec.py

@@ -75,7 +75,7 @@ def get_signature(self) -> Optional[inspect.Signature]:
 
         try:
             return inspect.signature(source)
-        except TypeError:
+        except (ValueError, TypeError):
             return None
 
     def get_class_type(self) -> Optional[Type[Any]]:

tests/common.py

@@ -22,6 +22,11 @@ def do_the_thing(self, *, flag: bool) -> None:
         """Perform a side-effect without a return value."""
         ...
 
+    @property
+    def primitive_property(self) -> str:
+        """Get a primitive computed property."""
+        ...
+
 
 class SomeNestedClass:
     """Nested testing class."""

tests/test_spec.py

@@ -118,6 +118,12 @@ class GetSignatureSpec(NamedTuple):
                 return_annotation=str,
             ),
         ),
+        GetSignatureSpec(
+            subject=Spec(source=SomeClass, name=None).get_child_spec(
+                "primitive_property"
+            ),
+            expected_signature=None,
+        ),
         GetSignatureSpec(
             subject=(
                 Spec(source=SomeNestedClass, name=None)