[python3] add vcpkg_get_vcpkg_installed_python (#38929)

ports/python3/portfile.cmake

@@ -384,4 +384,10 @@ else()
   file(COPY_FILE "${CURRENT_PACKAGES_DIR}/tools/python3/python3.${PYTHON_VERSION_MINOR}" "${CURRENT_PACKAGES_DIR}/tools/python3/python3")
 endif()
 
-configure_file("${CMAKE_CURRENT_LIST_DIR}/vcpkg-port-config.cmake" "${CURRENT_PACKAGES_DIR}/share/python3/vcpkg-port-config.cmake" @ONLY)
+configure_file("${CMAKE_CURRENT_LIST_DIR}/vcpkg-port-config.cmake" "${CURRENT_PACKAGES_DIR}/share/python3/vcpkg-port-config.cmake" @ONLY)
+
+# For testing
+block()
+  set(CURRENT_HOST_INSTALLED_DIR "${CURRENT_PACKAGES_DIR}")
+  vcpkg_get_vcpkg_installed_python(VCPKG_PYTHON3)
+endblocK()

ports/python3/vcpkg-port-config.cmake

@@ -10,3 +10,4 @@ else()
 endif()
 set(PYTHON3_SITE "${site_base}/site-packages")
 
+include("${CURRENT_HOST_INSTALLED_DIR}/share/vcpkg-get-python/vcpkg-port-config.cmake")

ports/python3/vcpkg.json

@@ -1,7 +1,7 @@
 {
   "name": "python3",
   "version": "3.11.8",
-  "port-version": 2,
+  "port-version": 3,
   "description": "The Python programming language",
   "homepage": "https://github.com/python/cpython",
   "license": "Python-2.0",
@@ -44,6 +44,10 @@
       "name": "sqlite3",
       "platform": "!(windows & static)"
     },
+    {
+      "name": "vcpkg-get-python",
+      "host": true
+    },
     {
       "name": "vcpkg-msbuild",
       "host": true,

ports/vcpkg-get-python/portfile.cmake

@@ -0,0 +1,7 @@
+
+file(INSTALL
+    "${CMAKE_CURRENT_LIST_DIR}/vcpkg-port-config.cmake"
+    DESTINATION "${CURRENT_PACKAGES_DIR}/share/${PORT}")
+
+vcpkg_install_copyright(FILE_LIST "${VCPKG_ROOT_DIR}/LICENSE.txt")
+set(VCPKG_POLICY_CMAKE_HELPER_PORT enabled)

ports/vcpkg-get-python/vcpkg-port-config.cmake

@@ -0,0 +1,46 @@
+function(vcpkg_get_vcpkg_installed_python out_python)
+  if(NOT VCPKG_TARGET_IS_WINDOWS)
+    # vcpkg installed python on !windows works as normal python would work.
+    set(${out_python} "${CURRENT_HOST_INSTALLED_DIR}/tools/python3/python3" PARENT_SCOPE)
+    return()
+  endif()
+
+  # On windows python is unable to lookup DLLs, so a manual venv is created
+  set(python_home "${CURRENT_HOST_INSTALLED_DIR}/tools/python3")
+  set(python_base "${CURRENT_BUILDTREES_DIR}/python-${TARGET_TRIPLET}")
+
+  file(GLOB python_files LIST_DIRECTORIES false "${python_home}/*")
+  if(EXISTS "${CURRENT_HOST_INSTALLED_DIR}/tools/python3/DLLs")
+    file(COPY "${CURRENT_HOST_INSTALLED_DIR}/tools/python3/DLLs/" DESTINATION "${python_base}/DLLs")
+  endif()
+  file(COPY ${python_files} DESTINATION "${python_base}/Scripts")
+  file(MAKE_DIRECTORY "${python_base}/Lib/site-packages")
+
+  file(WRITE "${python_base}/pyvenv.cfg"
+"
+home = ${python_home}
+include-system-site-packages = false
+version = ${PYTHON3_VERSION}
+executable = ${python_home}/python.exe
+command = ${python_home}/python.exe -m venv ${python_base}
+"
+)
+
+  file(WRITE "${python_base}/Lib/site-packages/sitecustomize.py"
+"
+import os
+import sys
+from pathlib import Path
+
+import site
+#enable direct lookup of installed site-packages without the need to copy them
+site.addsitedir(sys.base_prefix + '/Lib/site-packages')
+
+vcpkg_bin_path = Path(sys.base_prefix + '/../../bin')
+if vcpkg_bin_path.is_dir():
+  os.add_dll_directory(vcpkg_bin_path)
+"
+)
+
+ set(${out_python} "${python_base}/Scripts/python.exe" PARENT_SCOPE)
+endfunction()

ports/vcpkg-get-python/vcpkg.json

@@ -0,0 +1,6 @@
+{
+  "name": "vcpkg-get-python",
+  "version-date": "2024-06-08",
+  "license": "MIT",
+  "supports": "native"
+}

versions/baseline.json

@@ -7098,7 +7098,7 @@
     },
     "python3": {
       "baseline": "3.11.8",
-      "port-version": 2
+      "port-version": 3
     },
     "qca": {
       "baseline": "2.3.7",
@@ -9104,6 +9104,10 @@
       "baseline": "2023-12-31",
       "port-version": 0
     },
+    "vcpkg-get-python": {
+      "baseline": "2024-06-08",
+      "port-version": 0
+    },
     "vcpkg-get-python-packages": {
       "baseline": "2024-01-24",
       "port-version": 0

versions/p-/python3.json

@@ -1,5 +1,10 @@
 {
   "versions": [
+    {
+      "git-tree": "bd79c290d4768a376a9bb0de77cefb2e608e9bc7",
+      "version": "3.11.8",
+      "port-version": 3
+    },
     {
       "git-tree": "24bb8d2b3db0a12a7ca7f04061f632f0e94abcc2",
       "version": "3.11.8",

versions/v-/vcpkg-get-python.json

@@ -0,0 +1,9 @@
+{
+  "versions": [
+    {
+      "git-tree": "829be9eea1ad30190a8bb66e4c8a46c9c6d5b0f5",
+      "version-date": "2024-06-08",
+      "port-version": 0
+    }
+  ]
+}