Add py::module_local() attribute for module-local type bindings
This commit adds a `py::module_local` attribute that lets you confine a
registered type to the module (more technically, the shared object) in
which it is defined, by registering it with:
py::class_<C>(m, "C", py::module_local())
This will allow the same C++ class `C` to be registered in different
modules with independent sets of class definitions. On the Python side,
two such types will be completely distinct; on the C++ side, the C++
type resolves to a different Python type in each module.
This applies `py::module_local` automatically to `stl_bind.h` bindings
when the container value type looks like something global: i.e. when it
is a converting type (for example, when binding a `std::vector<int>`),
or when it is a registered type itself bound with `py::module_local`.
This should help resolve potential future conflicts (e.g. if two
completely unrelated modules both try to bind a `std::vector<int>`.
Users can override the automatic selection by adding a
`py::module_local()` or `py::module_local(false)`.
Note that this does mildly break backwards compatibility: bound stl
containers of basic types like `std::vector<int>` cannot be bound in one
module and returned in a different module. (This can be re-enabled with
`py::module_local(false)` as described above, but with the potential for
eventual load conflicts).
diff --git a/tests/test_class.cpp b/tests/test_class.cpp
index 8761f26..5860b74 100644
--- a/tests/test_class.cpp
+++ b/tests/test_class.cpp
@@ -9,6 +9,7 @@
#include "pybind11_tests.h"
#include "constructor_stats.h"
+#include "local_bindings.h"
TEST_SUBMODULE(class_, m) {
// test_instance
@@ -224,6 +225,10 @@
aliased.def(py::init<>());
aliased.attr("size_noalias") = py::int_(sizeof(AliasedHasOpNewDelSize));
aliased.attr("size_alias") = py::int_(sizeof(PyAliasedHasOpNewDelSize));
+
+ // This test is actually part of test_local_bindings (test_duplicate_local), but we need a
+ // definition in a different compilation unit within the same module:
+ bind_local<LocalExternal, 17>(m, "LocalExternal", py::module_local());
}
template <int N> class BreaksBase {};