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Python override of an inherited pure virtual operator() is not generated #146
Description
Observed with cppyy 3.5.0 (cppyy-cling 6.32.8) and cppjit 0.1.0a1 alike on 2026-10-08; the same
Python class shape works when the pure virtual has a plain name. Not cppjit-specific.
import cppyy # or cppjit; identical result
cppyy.cppdef(r'''
struct Impl { virtual ~Impl() {} virtual void operator()(int*) = 0; virtual void operator()() = 0;
virtual Impl* Clone() = 0; virtual bool IsStandalone() = 0; };
struct Standalone : Impl { void operator()(int*) override {} bool IsStandalone() override { return true; } };
struct NamedImpl { virtual ~NamedImpl() {} virtual void run() = 0; virtual void other() = 0; };
struct NamedMid : NamedImpl { void other() override {} };
''')
# works: a pure virtual with a plain name, inherited through an abstract intermediate class
type("A", (cppyy.gbl.NamedMid,), {"run": lambda self: None})()
# works: both operator() overloads pure in the direct base
# fails: pure operator()() inherited through Standalone, which implements the other overload
type("B", (cppyy.gbl.Standalone,), {"operator()": lambda self, *a: None, "Clone": lambda self: self})()
# TypeError: cannot instantiate abstract class '__cppyy_internal::Dispatcher1'Notes: the override must be registered under the C++ spelling "operator()" (a __call__ method
is not matched); that part is convention, not the defect. The defect is that the generated
dispatcher does not override the inherited pure operator()() when the intermediate base already
overrides operator()(int*), so the dispatcher class stays abstract. BioDynaMo's
StandaloneOperationImpl has exactly this shape. Workaround in act3/cartopiax_session.py: a
four-line C++ adapter that spells the pure virtual as Run().
Activity
Override inherited overloads a direct base implements only in part