pythonnet · lostmsu · Jan 5, 2021 · Jan 4, 2021
diff --git a/src/embed_tests/TestPyObject.cs b/src/embed_tests/TestPyObject.cs
@@ -59,9 +59,17 @@ def add(self, x, y):
        }

        [Test]
-        public void InvokeNull() {
+        public void InvokeNull()
+        {
            var list = PythonEngine.Eval("list");
            Assert.Throws<ArgumentNullException>(() => list.Invoke(new PyObject[] {null}));
        }
+
+        [Test]
+        public void AsManagedObjectInvalidCast()
+        {
+            var list = PythonEngine.Eval("list");
+            Assert.Throws<InvalidCastException>(() => list.AsManagedObject(typeof(int)));
+        }
    }
 }
diff --git a/src/runtime/delegatemanager.cs b/src/runtime/delegatemanager.cs
@@ -221,19 +221,17 @@ public void Dispose()
        public object Dispatch(ArrayList args)
        {
            IntPtr gs = PythonEngine.AcquireLock();
-            object ob = null;
+            object ob;

            try
            {
                ob = TrueDispatch(args);
            }
-            catch (Exception e)
+            finally
            {
                PythonEngine.ReleaseLock(gs);
-                throw e;
            }

-            PythonEngine.ReleaseLock(gs);
            return ob;
        }

@@ -266,27 +264,15 @@ public object TrueDispatch(ArrayList args)
                return null;
            }

-            object result = null;
-            if (!Converter.ToManaged(op, rtype, out result, false))
+            object result;
+            if (!Converter.ToManaged(op, rtype, out result, true))
            {
                Runtime.XDecref(op);
-                throw new ConversionException($"could not convert Python result to {rtype}");
+                throw new PythonException();
            }

            Runtime.XDecref(op);
            return result;
        }
    }
-
-
-    public class ConversionException : Exception
-    {
-        public ConversionException()
-        {
-        }
-
-        public ConversionException(string msg) : base(msg)
-        {
-        }
-    }
 }
diff --git a/src/runtime/pyobject.cs b/src/runtime/pyobject.cs
@@ -134,9 +134,9 @@ public static PyObject FromManagedObject(object ob)
        public object AsManagedObject(Type t)
        {
            object result;
-            if (!Converter.ToManaged(obj, t, out result, false))
+            if (!Converter.ToManaged(obj, t, out result, true))
            {
-                throw new InvalidCastException("cannot convert object to target type");
+                throw new InvalidCastException("cannot convert object to target type", new PythonException());
            }
            return result;
        }
@@ -154,12 +154,7 @@ public T As<T>()
            {
                return (T)(this as object);
            }
-            object result;
-            if (!Converter.ToManaged(obj, typeof(T), out result, false))
-            {
-                throw new InvalidCastException("cannot convert object to target type");
-            }
-            return (T)result;
+            return (T)AsManagedObject(typeof(T));
        }



diff --git a/src/tests/test_delegate.py b/src/tests/test_delegate.py
@@ -1,5 +1,4 @@
 # -*- coding: utf-8 -*-
-# TODO: Add test for ObjectDelegate

 """Test CLR delegate support."""

@@ -257,6 +256,26 @@ def always_so_negative():
    assert not d()
    assert not ob.CallBoolDelegate(d)

+def test_object_delegate():
+    """Test object delegate."""
+    from Python.Test import ObjectDelegate
+
+    def create_object():
+        return DelegateTest()
+
+    d = ObjectDelegate(create_object)
+    ob = DelegateTest()
+    ob.CallObjectDelegate(d)
+
+def test_invalid_object_delegate():
+    """Test invalid object delegate with mismatched return type."""
+    from Python.Test import ObjectDelegate
+
+    d = ObjectDelegate(hello_func)
+    ob = DelegateTest()
+    with pytest.raises(TypeError):
+        ob.CallObjectDelegate(d)
+
    # test async delegates

    # test multicast delegates