make .NET classes, that have __call__ method callable from Python #890

lostmsu · lostmsu · commit d46878c75acd · 2019-06-20T13:53:20.000-07:00
diff --git a/src/runtime/Python.Runtime.15.csproj b/src/runtime/Python.Runtime.15.csproj
@@ -19,7 +19,7 @@
     <SolutionDir Condition="$(SolutionDir) == '' Or $(SolutionDir) == '*Undefined*'">..\..\</SolutionDir>
     <PythonBuildDir Condition="'$(PythonBuildDir)' == ''">$(SolutionDir)\bin\</PythonBuildDir>
     <PublishDir>$(PythonBuildDir)\$(TargetFramework)\</PublishDir>
-    <LangVersion>6</LangVersion>
+    <LangVersion>7.3</LangVersion>
     <AllowUnsafeBlocks>True</AllowUnsafeBlocks>
     <AssemblyOriginatorKeyFile>..\pythonnet.snk</AssemblyOriginatorKeyFile>
     <CustomDefineConstants Condition="'$(CustomDefineConstants)' == ''">$(PYTHONNET_DEFINE_CONSTANTS)</CustomDefineConstants>
diff --git a/src/runtime/classobject.cs b/src/runtime/classobject.cs
@@ -1,5 +1,6 @@
 using System;
 using System.Reflection;
+using System.Runtime.InteropServices;
 
 namespace Python.Runtime
 {
@@ -294,7 +295,20 @@ public static IntPtr tp_call(IntPtr ob, IntPtr args, IntPtr kw)
 
             if (cb.type != typeof(Delegate))
             {
-                Exceptions.SetError(Exceptions.TypeError, "object is not callable");
+                IntPtr dict = Marshal.ReadIntPtr(tp, TypeOffset.tp_dict);
+                IntPtr methodObjectHandle = Runtime.PyDict_GetItemString(dict, "__call__");
+                if (methodObjectHandle == IntPtr.Zero || methodObjectHandle == Runtime.PyNone)
+                {
+                    Exceptions.SetError(Exceptions.TypeError, "object is not callable");
+                    return IntPtr.Zero;
+                }
+
+                if (GetManagedObject(methodObjectHandle) is MethodObject methodObject)
+                {
+                    return methodObject.Invoke(ob, args, kw);
+                }
+
+                Exceptions.SetError(Exceptions.TypeError, "instance has __call__, but it is not supported by Python.NET");
                 return IntPtr.Zero;
             }
 
