Tweaks related to Windows DOLFINx build

.github/workflows/windows.yml

@@ -53,6 +53,12 @@ jobs:
       VCPKG_BINARY_SOURCES: "clear;x-gha,readwrite"
     steps:
       - uses: actions/checkout@v4
+
+      - name: Insert add_dll_directory calls
+        working-directory: python/basix
+        run: |
+          (Get-Content __init__.py).Replace('# WINDOWSDLL', 'import os; os.add_dll_directory("D:/a/basix/install/bin")') | Set-Content __init__.py
+          Get-Content __init__.py
 
       - name: Export GitHub Actions cache environment variables
         uses: actions/github-script@v6
@@ -78,7 +84,6 @@ jobs:
           cd python
           python -m pip -v install --no-cache-dir .[ci] --config-settings=cmake.args=-DBasix_DIR=D:/a/basix/install/lib/cmake/basix
           cd ../
-          echo "import os; os.add_dll_directory('D:/a/basix/install/bin')" | Out-File -Append -FilePath conftest.py -Encoding utf8
 
       - name: Run units tests
         run: |

CMakeLists.txt

@@ -1,8 +1,4 @@
-if (WIN32)
-  cmake_minimum_required(VERSION 3.21)
-else()
-  cmake_minimum_required(VERSION 3.19)
-endif()
+cmake_minimum_required(VERSION 3.21)
 
 project(BasixFull VERSION "0.9.0.0" LANGUAGES CXX)
 set(BASIX_FULL_SKBUILD TRUE)

cpp/CMakeLists.txt

@@ -1,8 +1,4 @@
-if (WIN32)
-  cmake_minimum_required(VERSION 3.21)
-else()
-  cmake_minimum_required(VERSION 3.19)
-endif()
+cmake_minimum_required(VERSION 3.21)
 
 # Set the version
 project(Basix VERSION "0.9.0.0" LANGUAGES CXX)

cpp/vcpkg.json

@@ -2,6 +2,8 @@
   "$schema": "https://raw.githubusercontent.com/microsoft/vcpkg-tool/main/docs/vcpkg.schema.json",
   "dependencies": [
     "blas",
-    "lapack"
+    "lapack",
+    "vcpkg-cmake",
+    "vcpkg-cmake-config"
   ]
 }

python/CMakeLists.txt

@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 3.19)
+cmake_minimum_required(VERSION 3.21)
 
 # nanobind uses aligned deallocators only present on macOS > 10.14
 if(APPLE)

python/basix/__init__.py

@@ -9,6 +9,9 @@
 functionality can be used via this Python interface.
 """
 
+# Template placeholder for injecting Windows dll directories in CI
+# WINDOWSDLL
+
 from basix import cell, finite_element, lattice, polynomials, quadrature, sobolev_spaces
 from basix._basixcpp import __version__  # type: ignore
 from basix.cell import CellType, geometry, topology