Fix PyWeakRef_GetObject for ProxyType objects

Author: timfel

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/modules/cext/PythonCextWeakrefBuiltins.java

@@ -40,24 +40,26 @@
  */
 package com.oracle.graal.python.builtins.modules.cext;
 
-import static com.oracle.graal.python.nodes.BuiltinNames.T__WEAKREF;
-import static com.oracle.graal.python.nodes.BuiltinNames.T_PROXY_TYPE;
 import static com.oracle.graal.python.builtins.modules.cext.PythonCextBuiltins.CApiCallPath.Direct;
+import static com.oracle.graal.python.builtins.objects.cext.capi.transitions.ArgDescriptor.PYWEAKREFERENCE_PTR;
 import static com.oracle.graal.python.builtins.objects.cext.capi.transitions.ArgDescriptor.PyObject;
 import static com.oracle.graal.python.builtins.objects.cext.capi.transitions.ArgDescriptor.PyObjectBorrowed;
 import static com.oracle.graal.python.builtins.objects.cext.capi.transitions.ArgDescriptor.PyObjectTransfer;
-import static com.oracle.graal.python.builtins.objects.cext.capi.transitions.ArgDescriptor.PYWEAKREFERENCE_PTR;
 import static com.oracle.graal.python.builtins.objects.cext.capi.transitions.ArgDescriptor.Void;
+import static com.oracle.graal.python.nodes.BuiltinNames.T_PROXY_TYPE;
+import static com.oracle.graal.python.nodes.BuiltinNames.T__WEAKREF;
 
 import com.oracle.graal.python.builtins.PythonBuiltinClassType;
 import com.oracle.graal.python.builtins.modules.cext.PythonCextBuiltins.CApiBinaryBuiltinNode;
 import com.oracle.graal.python.builtins.modules.cext.PythonCextBuiltins.CApiBuiltin;
 import com.oracle.graal.python.builtins.modules.cext.PythonCextBuiltins.CApiUnaryBuiltinNode;
 import com.oracle.graal.python.builtins.objects.PNone;
 import com.oracle.graal.python.builtins.objects.module.PythonModule;
+import com.oracle.graal.python.builtins.objects.object.PythonObject;
 import com.oracle.graal.python.builtins.objects.referencetype.PReferenceType;
 import com.oracle.graal.python.builtins.objects.referencetype.ReferenceTypeBuiltins.ReferenceTypeNode;
 import com.oracle.graal.python.lib.PyObjectCallMethodObjArgs;
+import com.oracle.graal.python.nodes.attributes.ReadAttributeFromPythonObjectNode;
 import com.oracle.graal.python.runtime.PythonContext;
 import com.oracle.truffle.api.dsl.Bind;
 import com.oracle.truffle.api.dsl.Cached;
@@ -98,10 +100,19 @@ static Object refType(Object object, Object callback,
     @CApiBuiltin(ret = PyObjectBorrowed, args = {PyObject}, call = Direct)
     abstract static class PyWeakref_GetObject extends CApiUnaryBuiltinNode {
         @Specialization
-        static Object call(Object reference) {
+        static Object call(Object reference,
+                        @Bind Node inliningTarget,
+                        @Cached ReadAttributeFromPythonObjectNode read) {
             if (reference instanceof PReferenceType ref) {
                 return ref.getPyObject();
             }
+            if (reference instanceof PythonObject obj) {
+                // maybe a _weakref.py proxytype
+                Object weakref = read.execute(obj, T__WEAKREF);
+                if (weakref instanceof PReferenceType ref) {
+                    return ref.getPyObject();
+                }
+            }
             /*
              * This weak reference has died in the managed side due to its referent being collected.
              */