fix: get scikit-build example working

3 files changed, 49 insertions, 45 deletions

diff --git a/doc/source/f2py/code/CMakeLists_skbuild.txt b/doc/source/f2py/code/CMakeLists_skbuild.txt
index 97bc5c744..3d092760b 100644
--- a/doc/source/f2py/code/CMakeLists_skbuild.txt
+++ b/doc/source/f2py/code/CMakeLists_skbuild.txt
@@ -1,6 +1,5 @@
 ### setup project ###
-cmake_minimum_required(VERSION 3.17.3)
-set(CMAKE_CXX_STANDARD_REQUIRED ON)
+cmake_minimum_required(VERSION 3.9)
 
 project(fibby
   VERSION 1.0
@@ -16,74 +15,81 @@ if(PROJECT_SOURCE_DIR STREQUAL PROJECT_BINARY_DIR)
   )
 endif()
 
-# Grab Python
-find_package(Python3 3.9 REQUIRED
-  COMPONENTS Interpreter Development)
-
 # Ensure scikit-build modules
 if (NOT SKBUILD)
-  # Kanged -->https://github.com/Kitware/torch_liberator/blob/master/CMakeLists.txt
+  find_package(PythonInterp 3.7 REQUIRED)
+  # Kanged --> https://github.com/Kitware/torch_liberator/blob/master/CMakeLists.txt
   # If skbuild is not the driver; include its utilities in CMAKE_MODULE_PATH
   execute_process(
-  COMMAND "${Python3_EXECUTABLE}"
-  -c "import os, skbuild; print(os.path.dirname(skbuild.__file__))"
-  OUTPUT_VARIABLE SKBLD_DIR
-  OUTPUT_STRIP_TRAILING_WHITESPACE
+    COMMAND "${PYTHON_EXECUTABLE}"
+    -c "import os, skbuild; print(os.path.dirname(skbuild.__file__))"
+    OUTPUT_VARIABLE SKBLD_DIR
+    OUTPUT_STRIP_TRAILING_WHITESPACE
   )
-  set(SKBLD_CMAKE_DIR "${SKBLD_DIR}/resources/cmake")
-  list(APPEND CMAKE_MODULE_PATH ${SKBLD_CMAKE_DIR})
+  list(APPEND CMAKE_MODULE_PATH "${SKBLD_DIR}/resources/cmake")
+  message(STATUS "Looking in ${SKBLD_DIR}/resources/cmake for CMake modules")
 endif()
 
 # scikit-build style includes
 find_package(PythonExtensions REQUIRED) # for ${PYTHON_EXTENSION_MODULE_SUFFIX}
-find_package(NumPy REQUIRED) # for ${NumPy_INCLUDE_DIRS}
-find_package(F2PY REQUIRED) # for ${F2PY_INCLUDE_DIR}
+
+# Grab the variables from a local Python installation
+# NumPy headers
+execute_process(
+  COMMAND "${PYTHON_EXECUTABLE}"
+  -c "import numpy; print(numpy.get_include())"
+  OUTPUT_VARIABLE NumPy_INCLUDE_DIRS
+  OUTPUT_STRIP_TRAILING_WHITESPACE
+)
+# F2PY headers
+execute_process(
+  COMMAND "${PYTHON_EXECUTABLE}"
+  -c "import numpy.f2py; print(numpy.f2py.get_include())"
+  OUTPUT_VARIABLE F2PY_INCLUDE_DIR
+  OUTPUT_STRIP_TRAILING_WHITESPACE
+)
 
 # Prepping the module
 set(f2py_module_name "fibby")
 set(fortran_src_file "${CMAKE_SOURCE_DIR}/fib1.f")
-set(generated_module_file ${f2py_module_name}${PYTHON_EXTENSION_MODULE_SUFFIX})
+set(f2py_module_c "${f2py_module_name}module.c")
 
 # Target for enforcing dependencies
-add_custom_target(${f2py_module_name} ALL
+add_custom_target(genpyf
   DEPENDS "${fortran_src_file}"
-  )
-
-# Custom command for generating .c
+)
 add_custom_command(
-  OUTPUT "${f2py_module_name}module.c"
-  COMMAND ${F2PY_EXECUTABLE}
-    -m ${f2py_module_name}
-    ${fortran_src_file}
-    --lower
-  WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
-  DEPENDS ${fortran_src_file}
-  )
+  OUTPUT "${CMAKE_CURRENT_BINARY_DIR}/${f2py_module_c}"
+  COMMAND ${PYTHON_EXECUTABLE}  -m "numpy.f2py"
+                   "${fortran_src_file}"
+                   -m "fibby"
+                   --lower # Important
+  DEPENDS fib1.f # Fortran source
+)
 
-add_library(${generated_module_file} MODULE
+add_library(${CMAKE_PROJECT_NAME} MODULE
             "${f2py_module_name}module.c"
             "${F2PY_INCLUDE_DIR}/fortranobject.c"
             "${fortran_src_file}")
 
-target_include_directories(${generated_module_file} PUBLIC
-                           ${F2PY_INCLUDE_DIRS}
+target_include_directories(${CMAKE_PROJECT_NAME} PUBLIC
+                           ${F2PY_INCLUDE_DIR}
+                           ${NumPy_INCLUDE_DIRS}
                            ${PYTHON_INCLUDE_DIRS})
-set_target_properties(${generated_module_file} PROPERTIES SUFFIX "")
-set_target_properties(${generated_module_file} PROPERTIES PREFIX "")
+set_target_properties(${CMAKE_PROJECT_NAME} PROPERTIES SUFFIX "${PYTHON_EXTENSION_MODULE_SUFFIX}")
+set_target_properties(${CMAKE_PROJECT_NAME} PROPERTIES PREFIX "")
 
 # Linker fixes
 if (UNIX)
   if (APPLE)
-    set_target_properties(${generated_module_file} PROPERTIES
+    set_target_properties(${CMAKE_PROJECT_NAME} PROPERTIES
     LINK_FLAGS  '-Wl,-dylib,-undefined,dynamic_lookup')
   else()
-    set_target_properties(${generated_module_file} PROPERTIES
+    set_target_properties(${CMAKE_PROJECT_NAME} PROPERTIES
   LINK_FLAGS  '-Wl,--allow-shlib-undefined')
   endif()
 endif()
 
-if (SKBUILD)
-  install(TARGETS ${generated_module_file} DESTINATION fibby)
-else()
-  install(TARGETS ${generated_module_file} DESTINATION ${CMAKE_SOURCE_DIR}/fibby)
-endif()
+add_dependencies(${CMAKE_PROJECT_NAME} genpyf)
+
+install(TARGETS ${CMAKE_PROJECT_NAME} DESTINATION fibby)
diff --git a/doc/source/f2py/code/pyproj_skbuild.toml b/doc/source/f2py/code/pyproj_skbuild.toml
index 6686d1736..bcd6ae99c 100644
--- a/doc/source/f2py/code/pyproj_skbuild.toml
+++ b/doc/source/f2py/code/pyproj_skbuild.toml
@@ -1,5 +1,3 @@
-[project]
-requires-python = ">=3.7"
-
 [build-system]
-requires = ["setuptools>=42", "wheel", "scikit-build", "cmake>=3.18", "numpy>=1.21"]
+requires = ["setuptools>=42", "wheel", "scikit-build", "cmake>=3.9", "numpy>=1.21"]
+build-backend = "setuptools.build_meta"
diff --git a/doc/source/f2py/code/setup_skbuild.py b/doc/source/f2py/code/setup_skbuild.py
index 4dfc6af8b..28dcdcb1f 100644
--- a/doc/source/f2py/code/setup_skbuild.py
+++ b/doc/source/f2py/code/setup_skbuild.py
@@ -6,5 +6,5 @@ setup(
     description="a minimal example package (fortran version)",
     license="MIT",
     packages=['fibby'],
-    cmake_args=['-DSKBUILD=ON']
+    python_requires=">=3.7",
 )