New issue 2774: cpyext: pybind11: 'instancemethod' has no attribute '__name__' https://bitbucket.org/pypy/pypy/issues/2774/cpyext-pybind11-instancemethod-has-no
Andrew Stepanov: When I try to use this simple [pybind11](https://github.com/pybind/pybind11) binding code (which by the way compiles just fine under pypy3-v5.10.1): ``` #!cpp #include <pybind11/pybind11.h> class A { public: int field; }; namespace py = pybind11; PYBIND11_MODULE(simple, m) { py::class_<A>(m, "A") .def(py::init<>()) .def_readwrite("field", &A::field); } ``` I get ``` Traceback (most recent call last): File "<stdin>", line 1, in <module> ImportError: AttributeError: 'instancemethod' object has no attribute '__name__' ``` As it turns out, `InstanceMethod` indeed doesn't have `__name__` attribute (along with `__module__` and `__doc__` which pybind11 uses, see [pypy/module/cpyext/classobject.py:34](https://bitbucket.org/pypy/pypy/src/d12c359516b2ee430bd53958b2bc6bf3373b5557/pypy/module/cpyext/classobject.py?at=py3.5&fileviewer=file-view-default#classobject.py-34)) ``` InstanceMethod.typedef = TypeDef("instancemethod", __new__ = interp2app(InstanceMethod.descr_new), __call__ = interp2app(InstanceMethod.descr_call, descrmismatch='__call__'), __get__ = interp2app(InstanceMethod.descr_get), __repr__ = interp2app(InstanceMethod.descr_repr, descrmismatch='__repr__'), __func__= interp_attrproperty_w('w_function', cls=InstanceMethod), ) ``` When I implement them straightforwardly using `self.w_function` attributes ``` class InstanceMethod(W_Root): ... def fget_name(self, space): return space.getattr(self.w_function, space.newtext("__name__")) def fget_module(self, space): return space.getattr(self.w_function, space.newtext("__module__")) def fget_docstring(self, space): return space.getattr(self.w_function, space.newtext("__doc__")) ... InstanceMethod.typedef = TypeDef("instancemethod", ... __name__= GetSetProperty(InstanceMethod.fget_name, cls=InstanceMethod), __module__= GetSetProperty(InstanceMethod.fget_module, cls=InstanceMethod), __doc__= GetSetProperty(InstanceMethod.fget_docstring, cls=InstanceMethod), ) ``` everything works fine and example pybind11 module above can be imported with no problems. In fact, with this modifications all but the 2 tests (`test_multiple_inheritance.py`, `test_eval.py`) in pybind11 test suite pass, which makes the pybind11 library useful in practice (from my own experience: big binding library used in our private project compiles and passes all of our tests) _______________________________________________ pypy-issue mailing list pypy-issue@python.org https://mail.python.org/mailman/listinfo/pypy-issue
