From edf03ccd341e995fe122971c6c513641f6e1299c Mon Sep 17 00:00:00 2001
From: "Ralf W. Grosse-Kunstleve" <rwgk@google.com>
Date: Wed, 31 Jul 2024 13:41:34 -0700
Subject: [PATCH] Changes extracted from pybind11k commit
 f8128f0b0d712c210d7d4470a50acc88dc4604ea (PR #30005)

---
 CMakeLists.txt                           | 2 ++
 docs/classes.rst                         | 5 +++++
 include/pybind11/pytypes.h               | 6 +++++-
 tests/CMakeLists.txt                     | 1 +
 tests/extra_python_package/test_files.py | 2 ++
 5 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 0964e2eef..82eca8923 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -153,6 +153,7 @@ set(PYBIND11_HEADERS
     include/pybind11/detail/dynamic_raw_ptr_cast_if_possible.h
     include/pybind11/detail/init.h
     include/pybind11/detail/internals.h
+    include/pybind11/detail/native_enum_data.h
     include/pybind11/detail/smart_holder_poc.h
     include/pybind11/detail/type_caster_base.h
     include/pybind11/detail/typeid.h
@@ -175,6 +176,7 @@ set(PYBIND11_HEADERS
     include/pybind11/gil_safe_call_once.h
     include/pybind11/iostream.h
     include/pybind11/functional.h
+    include/pybind11/native_enum.h
     include/pybind11/numpy.h
     include/pybind11/operators.h
     include/pybind11/pybind11.h
diff --git a/docs/classes.rst b/docs/classes.rst
index 4f2167dac..1b165e8fa 100644
--- a/docs/classes.rst
+++ b/docs/classes.rst
@@ -553,3 +553,8 @@ The ``name`` property returns the name of the enum value as a unicode string.
 .. warning::
 
     Contrary to Python customs, enum values from the wrappers should not be compared using ``is``, but with ``==`` (see `#1177 <https://github.com/pybind/pybind11/issues/1177>`_ for background).
+
+.. note::
+
+    ``py::native_enum`` was added as an alternative to ``py::enum_``
+    with http://github.com/pybind/pybind11/pull/9999
diff --git a/include/pybind11/pytypes.h b/include/pybind11/pytypes.h
index f26c307a8..cb333f7af 100644
--- a/include/pybind11/pytypes.h
+++ b/include/pybind11/pytypes.h
@@ -48,6 +48,9 @@ PYBIND11_NAMESPACE_BEGIN(detail)
 class args_proxy;
 bool isinstance_generic(handle obj, const std::type_info &tp);
 
+template <typename T>
+bool isinstance_native_enum(handle obj, const std::type_info &tp);
+
 // Accessor forward declarations
 template <typename Policy>
 class accessor;
@@ -845,7 +848,8 @@ bool isinstance(handle obj) {
 
 template <typename T, detail::enable_if_t<!std::is_base_of<object, T>::value, int> = 0>
 bool isinstance(handle obj) {
-    return detail::isinstance_generic(obj, typeid(T));
+    return detail::isinstance_native_enum<T>(obj, typeid(T))
+           || detail::isinstance_generic(obj, typeid(T));
 }
 
 template <>
diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index 1007d6d82..1a3ef7149 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -162,6 +162,7 @@ set(PYBIND11_TEST_FILES
     test_methods_and_attributes
     test_modules
     test_multiple_inheritance
+    test_native_enum
     test_numpy_array
     test_numpy_dtypes
     test_numpy_vectorize
diff --git a/tests/extra_python_package/test_files.py b/tests/extra_python_package/test_files.py
index 5c9705371..e95ed4d36 100644
--- a/tests/extra_python_package/test_files.py
+++ b/tests/extra_python_package/test_files.py
@@ -39,6 +39,7 @@ main_headers = {
     "include/pybind11/gil.h",
     "include/pybind11/gil_safe_call_once.h",
     "include/pybind11/iostream.h",
+    "include/pybind11/native_enum.h",
     "include/pybind11/numpy.h",
     "include/pybind11/operators.h",
     "include/pybind11/options.h",
@@ -59,6 +60,7 @@ detail_headers = {
     "include/pybind11/detail/dynamic_raw_ptr_cast_if_possible.h",
     "include/pybind11/detail/init.h",
     "include/pybind11/detail/internals.h",
+    "include/pybind11/detail/native_enum_data.h",
     "include/pybind11/detail/smart_holder_poc.h",
     "include/pybind11/detail/type_caster_base.h",
     "include/pybind11/detail/typeid.h",