failing test

tests/CMakeLists.txt

@@ -151,7 +151,7 @@ function(pybind11_enable_warnings target_name)
   endif()
 endfunction()
 
-set(test_targets pybind11_tests)
+set(test_targets pybind11_tests test_move_arg)
 
 # Build pybind11_cross_module_tests if any test_whatever.py are being built that require it
 foreach(t ${PYBIND11_CROSS_MODULE_TESTS})

tests/test_move_arg.cpp

@@ -0,0 +1,31 @@
+#include "test_move_arg.h"
+#include <pybind11/pybind11.h>
+#include <pybind11/iostream.h>
+#include <sstream>
+
+namespace py = pybind11;
+
+PYBIND11_MODULE(test_move_arg, m) {
+	py::class_<Item>(m, "Item")
+		.def(py::init<int>(), py::call_guard<py::scoped_ostream_redirect>())
+		.def("__repr__", [](const Item& item) {
+			std::stringstream ss;
+			ss << "py " << item;
+			return ss.str();
+		}, py::call_guard<py::scoped_ostream_redirect>());
+
+	m.def("access", [](const Item& item) {
+		std::cout << "access " << item << "\n";
+	}, py::call_guard<py::scoped_ostream_redirect>());
+
+#if 0 // rvalue arguments fail during compilation
+	m.def("consume", [](Item&& item) {
+		std::cout << "consume " << item << "\n  ";
+		Item sink(std::move(item));
+		std::cout << "  old: " << item << "\n  new: " << sink << "\n";
+	}, py::call_guard<py::scoped_ostream_redirect>());
+#endif
+
+	m.def("working", [](int&& a) { std::cout << a << "\n"; },
+	      py::call_guard<py::scoped_ostream_redirect>());
+}

tests/test_move_arg.h

@@ -0,0 +1,34 @@
+#pragma once
+#include <memory>
+#include <vector>
+#include <iostream>
+
+class Item;
+std::ostream& operator<<(std::ostream& os, const Item& item);
+
+/** Item class requires unique instances, i.e. only supports move construction */
+class Item
+{
+public:
+  Item(int value) : value_(std::make_unique<int>(value)) {
+    std::cout<< "new " << *this << "\n";
+  }
+  ~Item() {
+    std::cout << "destroy " << *this << "\n";
+  }
+  Item(const Item&) = delete;
+  Item(Item&& other) {
+    std::cout << "move " << other << " -> ";
+    value_ = std::move(other.value_);
+    std::cout << *this << "\n";
+  }
+
+  std::unique_ptr<int> value_;
+};
+
+std::ostream& operator<<(std::ostream& os, const Item& item) {
+  os << "item " << &item << "(";
+  if (item.value_) os << *item.value_;
+  os << ")";
+  return os;
+}

tests/test_move_arg.py

@@ -0,0 +1,14 @@
+import pytest
+from test_move_arg import Item, access
+
+
+def test():
+    item = Item(42)
+    other = item
+    access(item)
+    print(item)
+    del item
+    print(other)
+
+if __name__ == "__main__":
+    test()