* Step 1: Establish new `PYBIND11_SMART_HOLDER_ENABLED` macro, but only under include/pybind11/
At the stage `PYBIND11_HAS_INTERNALS_WITH_SMART_HOLDER_SUPPORT` and `PYBIND11_SMART_HOLDER_ENABLED` are still equivalent.
* Systematically replace all `PYBIND11_HAS_INTERNALS_WITH_SMART_HOLDER_SUPPORT` with `PYBIND11_SMART_HOLDER_ENABLED` under tests/ and ubench/
As at the previous stage, `PYBIND11_HAS_INTERNALS_WITH_SMART_HOLDER_SUPPORT` and `PYBIND11_SMART_HOLDER_ENABLED` are still equivalent.
* Introduce `PYBIND11_SMART_HOLDER_DISABLE` option.
* `#ifdef` out entire `wrap()` function to avoid `unused-parameter` warning-as-error under macos-13
```
/Users/runner/work/pybind11/pybind11/tests/test_class_sh_trampoline_basic.cpp:67:23: error: unused parameter 'm' [-Werror,-Wunused-parameter]
void wrap(py::module_ m, const char *py_class_name) {
^
/Users/runner/work/pybind11/pybind11/tests/test_class_sh_trampoline_basic.cpp:67:38: error: unused parameter 'py_class_name' [-Werror,-Wunused-parameter]
void wrap(py::module_ m, const char *py_class_name) {
^
2 errors generated.
```
* Put bakein branch @ 18b72c0ffa on top of smart_holder branch:
Commands used:
```
git checkout bakein
git diff smart_holder > ~/zd
git checkout smart_holder
git checkout -b bakein_sh
patch -p 1 < ~/zd
git checkout smart_holder \
MANIFEST.in \
README.rst \
README_smart_holder.rst \
docs/advanced/smart_ptrs.rst \
ubench/holder_comparison.cpp \
ubench/holder_comparison.py \
ubench/holder_comparison_extract_sheet_data.py \
ubench/number_bucket.h \
ubench/python/number_bucket.clif
git add -A
```
* Add back README_smart_holder.rst in tests/extra_python_package/test_files.py
* Restore smart_holder_poc.h as-is on smart_holder branch (i.e. undo `PYBIND11_SMART_HOLDER_PADDING`, which was meant for stress-testing only).
* Insert `std::move()` as suggested by @laramiel
* `property_cpp_function_sh_*` named specializations, as suggested by @laramiel (https://github.com/pybind/pybind11/pull/5257#discussion_r1688346807)
* Call `property_cpp_function_classic` member functions, rather than inlining the implementations.
* Use `PYBIND11_HAVE_INTERNALS_WITH_SMART_HOLDER_SUPPORT` in holder_comparison.cpp (holder_comparison.py is NOT changed accordingly in this commit, i.e. can still only be run if the smart_holder functionality is available).
* Systematically rename `loaded_as` to `load_as` (`shared_ptr`, `unique_ptr`) as suggested by @laramiel
* Make change as suggested by @laramiel. This makes it much more obvious that the latest implementation of `smart_holder_from_unique_ptr()` accepts all existing `return_value_policy` enum values except `copy`.
* Resolve `BAKEIN_WIP: Rewrite comment.` for `property_cpp_function_*` specializations.
* Resolve `BAKEIN_WIP: Add comment to explain: This is meant for stress-testing only.`
* Resolve all remaining BAKEIN_WIP (in pybind11/cast.h).
Leave only two pairs of SMART_HOLDER_BAKEIN_FOLLOW_ON comments: refactoring of copyable_holder_caster, move_only_holder_caster. This is best left until after the smart_holder branch is merged into the master branch.
* Remove obsolete `using holder_type = smart_holder;` in `load_helper`
* Add SMART_HOLDER_BAKEIN_FOLLOW_ON comment for `internals::default_holder`
* README_smart_holder.rst update (line count reduced from 356 to 123).
* Using new smart_holder::reclaim_disowned in smart_holder_type_caster for unique_ptr.
* Systematically renaming was_disowned to is_disowned (because disowning is now reversible: reclaim_disowned).
* Systematically renaming virtual_overrider_self_life_support to trampoline_self_life_support (to reuse existing terminology instead of introducing new one).
* Systematically renaming test_class_sh_with_alias to test_class_sh_trampoline_basic.
* Adding a Trampolines and std::unique_ptr section to README_smart_holder.rst.
* MSVC compatibility.
* Adding test_class_sh_disowning.
* Fixing minor namespace naming inconsistency between test_class_sh_*.cpp files.
* Replacing py::overload_cast with plain cast for C++11 compatibility.
* Accommodate that the C++ order of evaluation of function arguments is unspecified.
* Adaption of PyCLIF virtual_py_cpp_mix test.
* Removing ValueError: Ownership of instance with virtual overrides in Python cannot be transferred to C++. TODO: static_assert alias class needs to inherit from virtual_overrider_self_life_support.
* Bringing back ValueError: "... instance cannot safely be transferred to C++.", but based on dynamic_cast<AliasType>.
* Fixing oversight: adding test_class_sh_virtual_py_cpp_mix.cpp to cmake file.
* clang <= 3.6 compatibility.
* Fixing oversight: dynamic_raw_ptr_cast_if_possible needs special handling for To = void. Adding corresponding missing test in test_class_sh_virtual_py_cpp_mix. Moving dynamic_raw_ptr_cast_if_possible to separate header.
* Changing py::detail::virtual_overrider_self_life_support to py::virtual_overrider_self_life_support.
