[python3] Add vcpkg-cmake-wrapper. (#15221)

* [python3] Add vcpkg-cmake-wrapper.cmake.

This is still a WIP... For now, we only remove registry detection on
Windows.

* [python3] Fix Windows static embedding linkage.

* [python3] Fix Linux static library embedding.

* [python3] Fix linkage on macOS.

* [python3] Only link extra libs when static.

* [python3] Bump port version for vcpkg-cmake-wrapper.

* [itk] Remove obsolete Python artifact specification.

* [pybind11] Remove obsolete Python artifact specification.

* [python3] Mark `find_package()` calls as REQUIRED.

Co-authored-by: Jack·Boos·Yu <47264268+JackBoosY@users.noreply.github.com>

* [python3] Bump port version after #15378.

* [python3] Be more selective about when to unleash the nukes.

* [python3] Add usage message.

* [python3] Don't swallow `vcpkg_find_acquire_program`'s Python3.

* [python3] Don't forcibly change the registry find state.

* [python3] fix copypasta error

* [python3] Fix config error with the opensubdiv port.

Co-authored-by: Jack·Boos·Yu <47264268+JackBoosY@users.noreply.github.com>
Co-authored-by: Billy Robert O'Neal III <bion@microsoft.com>

8 files changed, 153 insertions, 26 deletions

diff --git a/ports/itk/portfile.cmake b/ports/itk/portfile.cmake
index c89c65aa5..8961379a5 100644
--- a/ports/itk/portfile.cmake
+++ b/ports/itk/portfile.cmake
@@ -108,22 +108,6 @@ if("python" IN_LIST FEATURES)
         "-DSWIG_EXECUTABLE=${SWIG}"
         "-DSWIG_DIR=${SWIG_DIR}"
         )
-    # Due to ITKs internal shenanigans with the variables ......
-    if(VCPKG_TARGET_IS_WINDOWS)
-        list(APPEND ADDITIONAL_OPTIONS  "-DPython3_LIBRARY_RELEASE:PATH=${CURRENT_INSTALLED_DIR}/lib/python39.lib"
-                                        "-DPython3_LIBRARY_DEBUG:PATH=${CURRENT_INSTALLED_DIR}/debug/lib/python39_d.lib"
-                                        "-DPython3_INCLUDE_DIR:PATH=${CURRENT_INSTALLED_DIR}/include/python3.9")
-        list(APPEND OPTIONS_DEBUG "-DPython3_LIBRARY=${CURRENT_INSTALLED_DIR}/debug/lib/python39_d.lib")
-        list(APPEND OPTIONS_RELEASE "-DPython3_LIBRARY=${CURRENT_INSTALLED_DIR}/lib/python39.lib")
-    elseif(VCPKG_TARGET_IS_LINUX)
-        list(APPEND ADDITIONAL_OPTIONS  "-DPython3_LIBRARY_RELEASE:PATH=${CURRENT_INSTALLED_DIR}/lib/libpython39m.a"
-                                        "-DPython3_LIBRARY_DEBUG:PATH=${CURRENT_INSTALLED_DIR}/debug/lib/libpython39md.a"
-                                        "-DPython3_INCLUDE_DIR:PATH=${CURRENT_INSTALLED_DIR}/include/python3.9m")
-        list(APPEND OPTIONS_DEBUG "-DPython3_LIBRARY=${CURRENT_INSTALLED_DIR}/debug/lib/libpython39md.a")
-        list(APPEND OPTIONS_RELEASE "-DPython3_LIBRARY=${CURRENT_INSTALLED_DIR}/lib/libpython39m.a")
-    elseif(VCPKG_TARGET_IS_OSX)
-        #Need Python3 information on OSX within VCPKG
-    endif()
     #ITK_PYTHON_SITE_PACKAGES_SUFFIX should be set to the install dir of the site-packages within vcpkg
 endif()
 
diff --git a/ports/itk/vcpkg.json b/ports/itk/vcpkg.json
index 24de005c6..394b45afb 100644
--- a/ports/itk/vcpkg.json
+++ b/ports/itk/vcpkg.json
@@ -1,7 +1,7 @@
 {
   "name": "itk",
   "version-string": "5.1.0",
-  "port-version": 4,
+  "port-version": 5,
   "description": "Insight Segmentation and Registration Toolkit (ITK) is used for image processing and analysis.",
   "homepage": "https://github.com/InsightSoftwareConsortium/ITK",
   "dependencies": [
diff --git a/ports/pybind11/CONTROL b/ports/pybind11/CONTROL
index be711e1b1..8b14c31ec 100644
--- a/ports/pybind11/CONTROL
+++ b/ports/pybind11/CONTROL
@@ -1,6 +1,6 @@
 Source: pybind11
 Version: 2.6.0
-Port-Version: 1
+Port-Version: 2
 Homepage: https://github.com/pybind/pybind11
 Description: pybind11 is a lightweight header-only library that exposes C++ types in Python and vice versa, mainly to create Python bindings of existing C++ code.
 Build-Depends: python3 (windows)
diff --git a/ports/pybind11/portfile.cmake b/ports/pybind11/portfile.cmake
index 458c2a669..e227e0971 100644
--- a/ports/pybind11/portfile.cmake
+++ b/ports/pybind11/portfile.cmake
@@ -7,23 +7,18 @@ vcpkg_from_github(
 )
 
 vcpkg_find_acquire_program(PYTHON3)
-get_filename_component(PYPATH ${PYTHON3} PATH)
-vcpkg_add_to_path("${PYPATH}")
 
 vcpkg_configure_cmake(
     SOURCE_PATH ${SOURCE_PATH}
     PREFER_NINJA
     OPTIONS
         -DPYBIND11_TEST=OFF
-        -DPYTHONLIBS_FOUND=ON
-        -DPYTHON_INCLUDE_DIRS=${CURRENT_INSTALLED_DIR}/include
-        -DPYTHON_MODULE_EXTENSION=.dll
+        -DPYBIND11_FINDPYTHON=ON
+        -DPython3_EXECUTABLE=${PYTHON3}
     OPTIONS_RELEASE
         -DPYTHON_IS_DEBUG=OFF
-        -DPYTHON_LIBRARIES=${CURRENT_INSTALLED_DIR}/lib/python39.lib
     OPTIONS_DEBUG
         -DPYTHON_IS_DEBUG=ON
-        -DPYTHON_LIBRARIES=${CURRENT_INSTALLED_DIR}/debug/lib/python39_d.lib
 )
 
 vcpkg_install_cmake()
diff --git a/ports/python3/portfile.cmake b/ports/python3/portfile.cmake
index 711b317e0..72b4ee3bd 100644
--- a/ports/python3/portfile.cmake
+++ b/ports/python3/portfile.cmake
@@ -179,3 +179,19 @@ else()
 
     file(INSTALL "${SOURCE_PATH}/LICENSE" DESTINATION "${CURRENT_PACKAGES_DIR}/share/${PORT}" RENAME "copyright")
 endif()
+
+file(INSTALL "${CMAKE_CURRENT_LIST_DIR}/usage" DESTINATION "${CURRENT_PACKAGES_DIR}/share/${PORT}")
+
+function(_generate_finder)
+    cmake_parse_arguments(PythonFinder "NO_OVERRIDE" "DIRECTORY;PREFIX" "" ${ARGN})
+    configure_file(
+        "${CMAKE_CURRENT_LIST_DIR}/vcpkg-cmake-wrapper.cmake"
+        "${CURRENT_PACKAGES_DIR}/share/${PythonFinder_DIRECTORY}/vcpkg-cmake-wrapper.cmake"
+        @ONLY
+    )
+endfunction()
+
+message(STATUS "Installing cmake wrappers")
+_generate_finder(DIRECTORY "python" PREFIX "Python")
+_generate_finder(DIRECTORY "python3" PREFIX "Python3")
+_generate_finder(DIRECTORY "pythoninterp" PREFIX "PYTHON" NO_OVERRIDE)
diff --git a/ports/python3/usage b/ports/python3/usage
new file mode 100644
index 000000000..e177b11f6
--- /dev/null
+++ b/ports/python3/usage
@@ -0,0 +1,4 @@
+The package python3 is compatible with built-in CMake targets:

+

+    find_package(Python3 COMPONENTS Development REQUIRED)

+    target_link_libraries(main PRIVATE Python3::Python)

diff --git a/ports/python3/vcpkg-cmake-wrapper.cmake b/ports/python3/vcpkg-cmake-wrapper.cmake
new file mode 100644
index 000000000..83c3fbd1c
--- /dev/null
+++ b/ports/python3/vcpkg-cmake-wrapper.cmake
@@ -0,0 +1,120 @@
+# For very old ports whose upstream do not properly set the minimum CMake version.

+cmake_policy(SET CMP0012 NEW)

+cmake_policy(SET CMP0057 NEW)

+

+# This prevents the port's python.exe from overriding the Python fetched by

+# vcpkg_find_acquire_program(PYTHON3) and prevents the vcpkg toolchain from

+# stomping on FindPython's default functionality.

+list(REMOVE_ITEM CMAKE_PROGRAM_PATH "${_VCPKG_INSTALLED_DIR}/${VCPKG_TARGET_TRIPLET}/tools/python3")

+if(@PythonFinder_NO_OVERRIDE@)

+    _find_package(${ARGS})

+    return()

+endif()

+

+# CMake's FindPython's separation of concerns is very muddy. We only want to force vcpkg's Python

+# if the consumer is using the development component. What we don't want to do is break detection

+# of the system Python, which may have certain packages the user expects. But - if the user is

+# embedding Python or using both the development and interpreter components, then we need the

+# interpreter matching vcpkg's Python libraries. Note that the "Development" component implies

+# both "Development.Module" and "Development.Embed"

+if("Development" IN_LIST ARGS OR "Development.Embed" IN_LIST ARGS)

+    set(_PythonFinder_WantInterp TRUE)

+    set(_PythonFinder_WantLibs TRUE)

+elseif("Development.Module" IN_LIST ARGS)

+    if("Interpreter" IN_LIST ARGS)

+        set(_PythonFinder_WantInterp TRUE)

+    endif()

+    set(_PythonFinder_WantLibs TRUE)

+endif()

+

+if(_PythonFinder_WantLibs)

+    find_path(

+        @PythonFinder_PREFIX@_INCLUDE_DIR

+        NAMES "Python.h"

+        PATHS "${_VCPKG_INSTALLED_DIR}/${VCPKG_TARGET_TRIPLET}/include"

+        PATH_SUFFIXES "python@PYTHON_VERSION_MAJOR@.@PYTHON_VERSION_MINOR@"

+        NO_DEFAULT_PATH

+    )

+

+    # Don't set the public facing hint or the finder will be unable to detect the debug library.

+    # Internally, it uses the same value with an underscore prepended.

+    find_library(

+        _@PythonFinder_PREFIX@_LIBRARY_RELEASE

+        NAMES

+        "python@PYTHON_VERSION_MAJOR@@PYTHON_VERSION_MINOR@"

+        "python@PYTHON_VERSION_MAJOR@.@PYTHON_VERSION_MINOR@"

+        PATHS "${_VCPKG_INSTALLED_DIR}/${VCPKG_TARGET_TRIPLET}/lib"

+        NO_DEFAULT_PATH

+    )

+    find_library(

+        _@PythonFinder_PREFIX@_LIBRARY_DEBUG

+        NAMES

+        "python@PYTHON_VERSION_MAJOR@@PYTHON_VERSION_MINOR@_d"

+        "python@PYTHON_VERSION_MAJOR@.@PYTHON_VERSION_MINOR@d"

+        PATHS "${_VCPKG_INSTALLED_DIR}/${VCPKG_TARGET_TRIPLET}/debug/lib"

+        NO_DEFAULT_PATH

+    )

+

+    if(_PythonFinder_WantInterp)

+        find_program(

+            @PythonFinder_PREFIX@_EXECUTABLE

+            NAMES "python" "python@PYTHON_VERSION_MAJOR@.@PYTHON_VERSION_MINOR@"

+            PATHS "${_VCPKG_INSTALLED_DIR}/${VCPKG_TARGET_TRIPLET}/tools/python3"

+            NO_DEFAULT_PATH

+        )

+    endif()

+

+    _find_package(${ARGS})

+

+    if(@VCPKG_LIBRARY_LINKAGE@ STREQUAL static)

+        include(CMakeFindDependencyMacro)

+

+        # Python for Windows embeds the zlib module into the core, so we have to link against it.

+        # This is a separate extension module on Unix-like platforms.

+        if(WIN32)

+            find_dependency(ZLIB)

+            if(TARGET @PythonFinder_PREFIX@::Python)

+                set_property(TARGET @PythonFinder_PREFIX@::Python APPEND PROPERTY INTERFACE_LINK_LIBRARIES ZLIB::ZLIB)

+            endif()

+            if(TARGET @PythonFinder_PREFIX@::Module)

+                set_property(TARGET @PythonFinder_PREFIX@::Module APPEND PROPERTY INTERFACE_LINK_LIBRARIES ZLIB::ZLIB)

+            endif()

+            if(DEFINED @PythonFinder_PREFIX@_LIBRARIES)

+                list(APPEND @PythonFinder_PREFIX@_LIBRARIES ${ZLIB_LIBRARIES})

+            endif()

+        endif()

+

+        if(APPLE)

+            find_dependency(Iconv)

+            find_dependency(Intl)

+            if(TARGET @PythonFinder_PREFIX@::Python)

+                get_target_property(_PYTHON_INTERFACE_LIBS @PythonFinder_PREFIX@::Python INTERFACE_LINK_LIBRARIES)

+                list(REMOVE_ITEM _PYTHON_INTERFACE_LIBS "-liconv" "-lintl")

+                list(APPEND _PYTHON_INTERFACE_LIBS

+                    Iconv::Iconv

+                    "$<IF:$<CONFIG:Debug>,${Intl_LIBRARY_DEBUG},${Intl_LIBRARY_RELEASE}>"

+                )

+                set_property(TARGET @PythonFinder_PREFIX@::Python PROPERTY INTERFACE_LINK_LIBRARIES ${_PYTHON_INTERFACE_LIBS})

+                unset(_PYTHON_INTERFACE_LIBS)

+            endif()

+            if(TARGET @PythonFinder_PREFIX@::Module)

+                get_target_property(_PYTHON_INTERFACE_LIBS @PythonFinder_PREFIX@::Module INTERFACE_LINK_LIBRARIES)

+                list(REMOVE_ITEM _PYTHON_INTERFACE_LIBS "-liconv" "-lintl")

+                list(APPEND _PYTHON_INTERFACE_LIBS

+                    Iconv::Iconv

+                    "$<IF:$<CONFIG:Debug>,${Intl_LIBRARY_DEBUG},${Intl_LIBRARY_RELEASE}>"

+                )

+                set_property(TARGET @PythonFinder_PREFIX@::Module PROPERTY INTERFACE_LINK_LIBRARIES ${_PYTHON_INTERFACE_LIBS})

+                unset(_PYTHON_INTERFACE_LIBS)

+            endif()

+            if(DEFINED @PythonFinder_PREFIX@_LIBRARIES)

+                list(APPEND @PythonFinder_PREFIX@_LIBRARIES "-framework CoreFoundation" ${Iconv_LIBRARIES} ${Intl_LIBRARIES})

+            endif()

+        endif()

+    endif()

+else()

+    _find_package(${ARGS})

+endif()

+

+unset(_PythonFinder_WantInterp)

+unset(_PythonFinder_WantLibs)

diff --git a/ports/python3/vcpkg.json b/ports/python3/vcpkg.json
index b8aa2ac3c..d89136da3 100644
--- a/ports/python3/vcpkg.json
+++ b/ports/python3/vcpkg.json
@@ -1,7 +1,7 @@
 {
   "name": "python3",
   "version-string": "3.9.0",
-  "port-version": 2,
+  "port-version": 3,
   "description": "The Python programming language",
   "homepage": "https://github.com/python/cpython",
   "supports": "!(arm | uwp)",
@@ -12,10 +12,18 @@
     },
     "expat",
     {
+      "name": "gettext",
+      "platform": "osx"
+    },
+    {
       "name": "libffi",
       "platform": "!(windows & static)"
     },
     {
+      "name": "libiconv",
+      "platform": "osx"
+    },
+    {
       "name": "liblzma",
       "platform": "!(windows & static)"
     },