Fix regression: container pointers not castable
PR #936 broke the ability to return a pointer to a stl container (and,
likewise, to a tuple) because the added deduced type matched a
non-const pointer argument: the pointer-accepting `cast` in
PYBIND11_TYPE_CASTER had a `const type *`, which is a worse match for a
non-const pointer than the universal reference template #936 added.
This changes the provided TYPE_CASTER cast(ptr) to take the pointer by
template arg (so that it will accept either const or non-const pointer).
It has two other effects: it slightly reduces .so size (because many
type casters never actually need the pointer cast at all), and it allows
type casters to provide their untemplated pointer `cast()` that will
take precedence over the templated version provided in the macro.
diff --git a/include/pybind11/cast.h b/include/pybind11/cast.h
index 27d5622..33dc9f3 100644
--- a/include/pybind11/cast.h
+++ b/include/pybind11/cast.h
@@ -892,14 +892,15 @@
type value; \
public: \
static PYBIND11_DESCR name() { return type_descr(py_name); } \
- static handle cast(const type *src, return_value_policy policy, handle parent) { \
+ template <typename T_, enable_if_t<std::is_same<type, remove_cv_t<T_>>::value, int> = 0> \
+ static handle cast(T_ *src, return_value_policy policy, handle parent) { \
if (!src) return none().release(); \
return cast(*src, policy, parent); \
} \
operator type*() { return &value; } \
operator type&() { return value; } \
operator type&&() && { return std::move(value); } \
- template <typename _T> using cast_op_type = pybind11::detail::movable_cast_op_type<_T>
+ template <typename T_> using cast_op_type = pybind11::detail::movable_cast_op_type<T_>
template <typename CharT> using is_std_char_type = any_of<
diff --git a/tests/test_stl.cpp b/tests/test_stl.cpp
index 839c1af..6ba9cb9 100644
--- a/tests/test_stl.cpp
+++ b/tests/test_stl.cpp
@@ -38,6 +38,9 @@
// test_vector
m.def("cast_vector", []() { return std::vector<int>{1}; });
m.def("load_vector", [](const std::vector<int> &v) { return v.at(0) == 1 && v.at(1) == 2; });
+ // Unnumbered regression (caused by #936): pointers to stl containers aren't castable
+ static std::vector<RValueCaster> lvv{2};
+ m.def("cast_ptr_vector", []() { return &lvv; });
// test_array
m.def("cast_array", []() { return std::array<int, 2> {{1 , 2}}; });
@@ -78,7 +81,6 @@
v.back()[1].back().emplace("a", RValueCaster{});
return v;
});
- static std::vector<RValueCaster> lvv{2};
static std::array<RValueCaster, 2> lva;
static std::unordered_map<std::string, RValueCaster> lvm{{"a", RValueCaster{}}, {"b", RValueCaster{}}};
static std::unordered_map<std::string, std::vector<std::list<std::array<RValueCaster, 2>>>> lvn;
diff --git a/tests/test_stl.py b/tests/test_stl.py
index 0f01982..c2fa7db 100644
--- a/tests/test_stl.py
+++ b/tests/test_stl.py
@@ -15,6 +15,9 @@
assert doc(m.cast_vector) == "cast_vector() -> List[int]"
assert doc(m.load_vector) == "load_vector(arg0: List[int]) -> bool"
+ # Test regression caused by 936: pointers to stl containers weren't castable
+ assert m.cast_ptr_vector() == ["lvalue", "lvalue"]
+
def test_array(doc):
"""std::array <-> list"""