pybind11/tests/test_local_bindings.cpp
Jason Rhinelander 4b159230d9 Made module_local types take precedence over global types
Attempting to mix py::module_local and non-module_local classes results
in some unexpected/undesirable behaviour:

- if a class is registered non-local by some other module, a later
  attempt to register it locally fails.  It doesn't need to: it is
  perfectly acceptable for the local registration to simply override
  the external global registration.
- going the other way (i.e. module `A` registers a type `T` locally,
  then `B` registers the same type `T` globally) causes a more serious
  issue: `A.T`'s constructors no longer work because the `self` argument
  gets converted to a `B.T`, which then fails to resolve.

Changing the cast precedence to prefer local over global fixes this and
makes it work more consistently, regardless of module load order.
2017-08-05 11:23:34 -04:00

75 lines
3.3 KiB
C++

/*
tests/test_local_bindings.cpp -- tests the py::module_local class feature which makes a class
binding local to the module in which it is defined.
Copyright (c) 2017 Jason Rhinelander <jason@imaginary.ca>
All rights reserved. Use of this source code is governed by a
BSD-style license that can be found in the LICENSE file.
*/
#include "pybind11_tests.h"
#include "local_bindings.h"
#include <pybind11/stl_bind.h>
TEST_SUBMODULE(local_bindings, m) {
// test_local_bindings
// Register a class with py::module_local:
bind_local<LocalType, -1>(m, "LocalType", py::module_local())
.def("get3", [](LocalType &t) { return t.i + 3; })
;
m.def("local_value", [](LocalType &l) { return l.i; });
// test_nonlocal_failure
// The main pybind11 test module is loaded first, so this registration will succeed (the second
// one, in pybind11_cross_module_tests.cpp, is designed to fail):
bind_local<NonLocalType, 0>(m, "NonLocalType")
.def(py::init<int>())
.def("get", [](LocalType &i) { return i.i; })
;
// test_duplicate_local
// py::module_local declarations should be visible across compilation units that get linked together;
// this tries to register a duplicate local. It depends on a definition in test_class.cpp and
// should raise a runtime error from the duplicate definition attempt. If test_class isn't
// available it *also* throws a runtime error (with "test_class not enabled" as value).
m.def("register_local_external", [m]() {
auto main = py::module::import("pybind11_tests");
if (py::hasattr(main, "class_")) {
bind_local<LocalExternal, 7>(m, "LocalExternal", py::module_local());
}
else throw std::runtime_error("test_class not enabled");
});
// test_stl_bind_local
// stl_bind.h binders defaults to py::module_local if the types are local or converting:
py::bind_vector<std::vector<LocalType>>(m, "LocalVec");
py::bind_map<std::unordered_map<std::string, LocalType>>(m, "LocalMap");
// and global if the type (or one of the types, for the map) is global:
py::bind_vector<std::vector<NonLocalType>>(m, "NonLocalVec");
py::bind_map<std::unordered_map<std::string, NonLocalType>>(m, "NonLocalMap");
// test_stl_bind_global
// They can, however, be overridden to global using `py::module_local(false)`:
bind_local<NonLocal2, 10>(m, "NonLocal2");
py::bind_vector<std::vector<NonLocal2>>(m, "LocalVec2", py::module_local());
py::bind_map<std::unordered_map<std::string, uint8_t>>(m, "NonLocalMap2", py::module_local(false));
// test_mixed_local_global
// We try this both with the global type registered first and vice versa (the order shouldn't
// matter).
m.def("register_mixed_global", [m]() {
bind_local<MixedGlobalLocal, 100>(m, "MixedGlobalLocal", py::module_local(false));
});
m.def("register_mixed_local", [m]() {
bind_local<MixedLocalGlobal, 1000>(m, "MixedLocalGlobal", py::module_local());
});
m.def("get_mixed_gl", [](int i) { return MixedGlobalLocal(i); });
m.def("get_mixed_lg", [](int i) { return MixedLocalGlobal(i); });
// test_internal_locals_differ
m.def("local_cpp_types_addr", []() { return (uintptr_t) &py::detail::registered_local_types_cpp(); });
}