[lldb] Handle staticmethod/classmethod descriptors in ScriptedPythonInterface

[medismailben]

Extract __func__ attribute from staticmethod/classmethod descriptors before treating them as callables. Python's @staticmethod and @classmethod decorators wrap methods in descriptor objects that are not directly usable as PythonCallable, when calling PyCallable_Check.

The actual callable function is stored in the __func__ attribute of these descriptors, so we need to unwrap them to properly validate and invoke the decorated methods in scripted interfaces.

[llvmbot]

@llvm/pr-subscribers-lldb

Author: Med Ismail Bennani (medismailben)

Changes

Extract __func__ attribute from staticmethod/classmethod descriptors before treating them as callables. Python's @staticmethod and @classmethod decorators wrap methods in descriptor objects that are not directly usable as PythonCallable, when calling PyCallable_Check.

The actual callable function is stored in the __func__ attribute of these descriptors, so we need to unwrap them to properly validate and invoke decorated methods in scripted interfaces.

---

Full diff: https://github.com/llvm/llvm-project/pull/170188.diff

1 Files Affected:

• (modified) lldb/source/Plugins/ScriptInterpreter/Python/Interfaces/ScriptedPythonInterface.h (+11-1)

diff --git a/lldb/source/Plugins/ScriptInterpreter/Python/Interfaces/ScriptedPythonInterface.h b/lldb/source/Plugins/ScriptInterpreter/Python/Interfaces/ScriptedPythonInterface.h
index af88a69e34a13..d9cebefff5ff5 100644
--- a/lldb/source/Plugins/ScriptInterpreter/Python/Interfaces/ScriptedPythonInterface.h
+++ b/lldb/source/Plugins/ScriptInterpreter/Python/Interfaces/ScriptedPythonInterface.h
@@ -81,7 +81,17 @@ class ScriptedPythonInterface : virtual public ScriptedInterface {
                               AbstractMethodCheckerCases::eNotAllocated)
       }
 
-      PythonCallable callable = callable_or_err->AsType<PythonCallable>();
+      PythonObject method_obj = *callable_or_err;
+
+      // Handle staticmethod/classmethod descriptors by extracting __func__
+      if (method_obj.HasAttribute("__func__")) {
+        method_obj = method_obj.GetAttributeValue("__func__");
+        if (!method_obj.IsAllocated())
+          SET_CASE_AND_CONTINUE(method_name,
+                                AbstractMethodCheckerCases::eNotAllocated)
+      }
+
+      PythonCallable callable = method_obj.AsType<PythonCallable>();
       if (!callable)
         SET_CASE_AND_CONTINUE(method_name,
                               AbstractMethodCheckerCases::eNotCallable)

[JDevlieghere]

Do you think we may need this logic elsewhere? If so, would it make sense to put this into a static method in PythonCallable? Something like Expected<PythonCallable> PythonCallable::GetCallable(PythonObject* object)?

[medismailben]

I moved this as part of static bool PythonCallable::Check which I think makes most sense. T::Check gets invoked when calling T PythonObject::AsType<T>.

[JDevlieghere]

Nice