Update example to reproduce wjakob/nanobind#69

CMakeLists.txt

@@ -18,18 +18,8 @@ elseif (MSVC)
   find_package(Python)
 endif()
 
-find_package(Python COMPONENTS Interpreter Development.Module REQUIRED)
-
-# Run `nanobind.cmake_dir()` from Python to detect install location
-execute_process(
-  COMMAND
-  "${PYTHON_EXECUTABLE}" -c "import nanobind; print(nanobind.cmake_dir())"
-  OUTPUT_VARIABLE _tmp_dir
-  OUTPUT_STRIP_TRAILING_WHITESPACE COMMAND_ECHO STDOUT)
-list(APPEND CMAKE_PREFIX_PATH "${_tmp_dir}")
-
-# Now import nanobind from CMake
-find_package(nanobind CONFIG REQUIRED)
+list(PREPEND CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/cmake)
+include(nanobind)
 
 # Build the actual extension module
 nanobind_add_module(

cmake/nanobind.cmake

@@ -0,0 +1,31 @@
+#
+# Copyright 2022 Adobe. All rights reserved.
+# This file is licensed to you under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License. You may obtain a copy
+# of the License at http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software distributed under
+# the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR REPRESENTATIONS
+# OF ANY KIND, either express or implied. See the License for the specific language
+# governing permissions and limitations under the License.
+#
+if(COMMAND nanobind_add_module)
+    return()
+endif()
+
+message(STATUS "Third-party (external): creating target 'nanobind::nanobind'")
+
+include(FetchContent)
+FetchContent_Declare(
+    nanobind
+    GIT_REPOSITORY https://github.com/wjakob/nanobind.git
+    GIT_TAG master
+)
+
+include(python)
+set(NB_SHARED OFF CACHE INTERNAL "")
+
+# Note that we do not use FetchContent_MakeAvailable here because nanobind's cmake changes
+# CMAKE_CXX_FLAGS and attempts to refind python, which can leads to cmake error.
+FetchContent_Populate(nanobind)
+find_package(nanobind PATHS ${nanobind_SOURCE_DIR}/cmake NO_DEFAULT_PATH)

cmake/python.cmake

@@ -0,0 +1,17 @@
+#
+# Copyright 2022 Adobe. All rights reserved.
+# This file is licensed to you under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License. You may obtain a copy
+# of the License at http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software distributed under
+# the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR REPRESENTATIONS
+# OF ANY KIND, either express or implied. See the License for the specific language
+# governing permissions and limitations under the License.
+#
+if(TARGET Python::Module)
+    return()
+endif()
+
+set(Python_FIND_VIRTUALENV FIRST)
+find_package(Python 3.8 COMPONENTS Interpreter Development.Module REQUIRED)

pyproject.toml

@@ -2,9 +2,8 @@
 requires = [
     "setuptools>=42",
     "wheel",
-    "scikit-build==0.14.0",
+    "scikit-build==0.15.0",
     "cmake>=3.18",
-    "nanobind>=0.0.3",
     "ninja; platform_system!='Windows'"
 ]
 

setup.py

@@ -2,7 +2,6 @@
 
 try:
     from skbuild import setup
-    import nanobind
 except ImportError:
     print("The preferred way to invoke 'setup.py' is via pip, as in 'pip "
           "install .'. If you wish to run the setup script directly, you must "

src/nanobind_example/__init__.py

@@ -1 +1 @@
-from .nanobind_example_ext import add
+from .nanobind_example_ext import add, Color, print_color, ColorMap

src/nanobind_example_ext.cpp

@@ -1,9 +1,59 @@
 #include <nanobind/nanobind.h>
 
+#include <iostream>
+
 namespace nb = nanobind;
 
 using namespace nb::literals;
 
+enum Color { Red, Green, Blue };
+
+class ColorMap {
+   public:
+    ColorMap() = default;
+};
+
 NB_MODULE(nanobind_example_ext, m) {
-    m.def("add", [](int a, int b) { return a + b; }, "a"_a, "b"_a);
+    nb::enum_<Color>(m, "Color")
+        .value("Red", Color::Red)
+        .value("Green", Color::Green)
+        .value("Blue", Color::Blue);
+
+    m.def(
+        "add", [](int a, int b) { return a + b; }, "a"_a, "b"_a);
+    m.def(
+        "print_color",
+        [](Color c) {
+            switch (c) {
+                case Color::Red:
+                    std::cout << "red" << std::endl;
+                    break;
+                case Color::Green:
+                    std::cout << "green" << std::endl;
+                    break;
+                case Color::Blue:
+                    std::cout << "blue" << std::endl;
+                    break;
+            }
+        },
+        "color"_a = Color::Red);
+
+    nb::class_<ColorMap>(m, "ColorMap")
+        .def(nb::init<>())
+        .def(
+            "print_color",
+            [](ColorMap& self, Color c) {
+                switch (c) {
+                    case Color::Red:
+                        std::cout << "red" << std::endl;
+                        break;
+                    case Color::Green:
+                        std::cout << "green" << std::endl;
+                        break;
+                    case Color::Blue:
+                        std::cout << "blue" << std::endl;
+                        break;
+                }
+            },
+            "color"_a = Color::Red);
 }