python-helpers.cmake

# Copyright (C) 2008-2023 LAAS-CNRS, JRL AIST-CNRS, INRIA.
#
# This program is free software: you can redistribute it and/or modify it under
# the terms of the GNU General Public License as published by the Free Software
# Foundation, either version 3 of the License, or (at your option) any later
# version.
#
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
# details.
#
# You should have received a copy of the GNU General Public License along with
# this program.  If not, see <http://www.gnu.org/licenses/>.

# .rst:
#
# ~~~
# .. command:: PYTHON_INSTALL(<module> <file> <dest> COMPONENT <component>)
# ~~~
#
# Compile and install a Python file.
#
# :param module: Python module name.
#
# :param file: Python file name.
#
# :param file: Installation directory.
#
# :param component: Component to forward to install command.
macro(PYTHON_INSTALL MODULE FILE DEST)
  set(options)
  set(oneValueArgs COMPONENT)
  set(multiValueArgs)
  cmake_parse_arguments(
    ARGS
    "${options}"
    "${oneValueArgs}"
    "${multiValueArgs}"
    ${ARGN}
  )

  if(ARGS_COMPONENT)
    set(_COMPONENT_NAME ${ARGS_COMPONENT})
  else()
    set(_COMPONENT_NAME ${CMAKE_INSTALL_DEFAULT_COMPONENT_NAME})
  endif()

  PYTHON_BUILD("${MODULE}" "${FILE}")

  install(
    FILES "${CMAKE_CURRENT_SOURCE_DIR}/${MODULE}/${FILE}"
    DESTINATION "${DEST}/${MODULE}"
    COMPONENT ${_COMPONENT_NAME}
  )
endmacro()

# .rst:
#
# ~~~
# .. command:: PYTHON_INSTALL_ON_SITE (<module> <file> COMPONENT <component>)
# ~~~
#
# Compile and install a Python file in :cmake:variable:`PYTHON_SITELIB`.
#
# :param module: Python module name.
#
# :param file: Python file name.
#
# :param component: Component to forward to install command.
macro(PYTHON_INSTALL_ON_SITE MODULE FILE)
  set(options)
  set(oneValueArgs COMPONENT)
  set(multiValueArgs)
  cmake_parse_arguments(
    ARGS
    "${options}"
    "${oneValueArgs}"
    "${multiValueArgs}"
    ${ARGN}
  )

  if(ARGS_COMPONENT)
    set(_COMPONENT_NAME ${ARGS_COMPONENT})
  else()
    set(_COMPONENT_NAME ${CMAKE_INSTALL_DEFAULT_COMPONENT_NAME})
  endif()

  PYTHON_INSTALL(
    "${MODULE}"
    "${FILE}"
    ${PYTHON_SITELIB}
    COMPONENT ${_COMPONENT_NAME}
  )
endmacro()

# PYTHON_BUILD_GET_TARGET(TARGET)
# -----------------------------------------
#
# Get the target associated to the PYTHON_BUILD procedure
#
function(PYTHON_BUILD_GET_TARGET python_build_target)
  # Regex from IsValidTargetName in CMake/Source/cmGeneratorExpression.cxx
  string(
    REGEX REPLACE
    "[^A-Za-z0-9_.+-]"
    "_"
    compile_pyc
    "${PROJECT_NAME}_compile_pyc_${CMAKE_CURRENT_SOURCE_DIR}"
  )

  if(NOT TARGET ${compile_pyc})
    add_custom_target(${compile_pyc} ALL)
  endif()

  set(${python_build_target} ${compile_pyc} PARENT_SCOPE)
endfunction(PYTHON_BUILD_GET_TARGET NAME)

# PYTHON_BUILD(MODULE FILE DEST)
# --------------------------------------
#
# Build a Python file from the source directory in the build directory.
#
macro(PYTHON_BUILD MODULE FILE)
  set(python_build_target "")
  PYTHON_BUILD_GET_TARGET(python_build_target)

  set(INPUT_FILE "${CMAKE_CURRENT_SOURCE_DIR}/${MODULE}/${FILE}")

  if(CMAKE_GENERATOR MATCHES "Visual Studio|Xcode")
    set(OUTPUT_FILE_DIR "${CMAKE_CURRENT_BINARY_DIR}/${MODULE}/$<CONFIG>")
  else()
    set(OUTPUT_FILE_DIR "${CMAKE_CURRENT_BINARY_DIR}/${MODULE}")
  endif()

  set(OUTPUT_FILE "${OUTPUT_FILE_DIR}/${FILE}c")

  # Create directory accounting for the generator expression contained in
  # ${OUTPUT_FILE_DIR}
  add_custom_command(
    TARGET ${python_build_target}
    PRE_BUILD
    COMMAND ${CMAKE_COMMAND} -E make_directory "${OUTPUT_FILE_DIR}"
  )

  PYTHON_BUILD_FILE(${INPUT_FILE} ${OUTPUT_FILE})
endmacro()

# PYTHON_BUILD_FILE(FILE [OUTPUT_FILE])
# --------------------------------------
#
# Build a Python a given file.
#
macro(PYTHON_BUILD_FILE FILE)
  set(python_build_target "")
  PYTHON_BUILD_GET_TARGET(python_build_target)

  set(extra_var "${ARGV1}")
  if(NOT extra_var STREQUAL "")
    set(OUTPUT_FILE "${ARGV1}")
  else()
    set(OUTPUT_FILE "${FILE}c")
  endif()

  add_custom_command(
    TARGET ${python_build_target}
    PRE_BUILD
    COMMAND
      "${PYTHON_EXECUTABLE}" -c
      "import py_compile; py_compile.compile(\"${FILE}\",\"${OUTPUT_FILE}\")"
    VERBATIM
  )

  # Tag pyc file as generated.
  set_source_files_properties("${OUTPUT_FILE}" PROPERTIES GENERATED TRUE)

  # Clean generated files.
  set_property(
    DIRECTORY
    APPEND
    PROPERTY ADDITIONAL_MAKE_CLEAN_FILES "${OUTPUT_FILE}"
  )
endmacro()