Merge pull request #384 from jagerman/unique-ptr-non-default-deleters

Make unique_ptr's with non-default deleters work

include/pybind11/cast.h

@@ -498,9 +498,9 @@ protected:
     bool success = false;
 };
 
-template <typename type> class type_caster<std::unique_ptr<type>> {
+template <typename type, typename deleter> class type_caster<std::unique_ptr<type, deleter>> {
 public:
-    static handle cast(std::unique_ptr<type> &&src, return_value_policy policy, handle parent) {
+    static handle cast(std::unique_ptr<type, deleter> &&src, return_value_policy policy, handle parent) {
         handle result = type_caster_base<type>::cast(src.get(), policy, parent);
         if (result)
             src.release();

tests/test_smart_ptr.cpp

@@ -69,6 +69,18 @@ private:
     int value;
 };
 
+class MyObject4 {
+public:
+    MyObject4(int value) : value{value} {
+        print_created(this);
+    }
+    int value;
+private:
+    ~MyObject4() {
+        print_destroyed(this);
+    }
+};
+
 /// Make pybind aware of the ref-counted wrapper type (s)
 PYBIND11_DECLARE_HOLDER_TYPE(T, ref<T>);
 PYBIND11_DECLARE_HOLDER_TYPE(T, std::shared_ptr<T>);
@@ -143,6 +155,10 @@ test_initializer smart_ptr([](py::module &m) {
     m.def("print_myobject3_3", &print_myobject3_3);
     m.def("print_myobject3_4", &print_myobject3_4);
 
+    py::class_<MyObject4, std::unique_ptr<MyObject4, py::nodelete>>(m, "MyObject4")
+        .def(py::init<int>())
+        .def_readwrite("value", &MyObject4::value);
+
     py::implicitly_convertible<py::int_, MyObject1>();
 
     // Expose constructor stats for the ref type

tests/test_smart_ptr.py

@@ -113,3 +113,13 @@ def test_smart_ptr(capture):
     # assert cstats.move_constructions >= 0 # Doesn't invoke any
     assert cstats.copy_assignments == 30
     assert cstats.move_assignments == 0
+
+def test_unique_nodelete(capture):
+    from pybind11_tests import MyObject4
+    o = MyObject4(23)
+    assert o.value == 23
+    cstats = ConstructorStats.get(MyObject4)
+    assert cstats.alive() == 1
+    del o
+    cstats = ConstructorStats.get(MyObject4)
+    assert cstats.alive() == 1 # Leak, but that's intentional