Qualification in compound return types

[phdum]

Hi,

I ran across a problem where a locally defined type was not fully qualified when it was part of a compound return type.

Here a minimal example test.hpp:

#pragma once

#include <utility>
#include <tuple>
#include <triqs/utility/first_include.hpp>

namespace test_namespace {

class test_class {
 public:
  using return_t = double;
  std::pair<return_t, double> test_function_bad() { return std::make_pair(0.0, 0.0); }
  return_t test_function_good() { return std::make_pair(0.0, 0.0); }
};

} // namespace test_namespace

If we run c++2py on this:

# Generated automatically using the command :
# c++2py tmp.hpp -N test_namespace
from cpp2py.wrap_generator import *

# The module
module = module_(full_name = "tmp", doc = r"", app_name = "tmp")

# Imports

# Add here all includes
module.add_include("tmp.hpp")

# Add here anything to add in the C++ code at the start, e.g. namespace using
module.add_preamble("""
#include <cpp2py/converters/pair.hpp>

using namespace test_namespace;
""")


# The class test_class
c = class_(
        py_type = "TestClass",  # name of the python class
        c_type = "test_namespace::test_class",   # name of the C++ class
        doc = r"""""",   # doc of the C++ class
        hdf5 = False,
)

c.add_method("""std::pair<return_t,double> test_function_bad ()""",
             doc = r"""""")

c.add_method("""test_namespace::test_class::return_t test_function_good ()""",
             doc = r"""""")

module.add_class(c)



module.generate_code()

Here return_t is not correctly qualified as part of the return type in test_function_bad(). This leads to a "use of undeclared identifier" error when compiling. Contrast to the correct behaviour in test_function_good().

I'm guessing that c++2py would need to recursively step into the compound return type to check that everything is fully qualified?

[PS: I'm using the c++2py bundled with TRIQS 2.2.x]