CMake/Modules/FindRuby.cmake

# Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
# file Copyright.txt or https://cmake.org/licensing for details.

#[=======================================================================[.rst:
FindRuby
--------

This module determines if Ruby is installed and finds the locations of its
include files and libraries. Ruby 1.8 through 3.4 are supported.

The minimum required version of Ruby can be specified using the
standard syntax, e.g.

.. code-block:: cmake

  find_package(Ruby 3.2.6 EXACT REQUIRED)
  # OR
  find_package(Ruby 3.2)

Virtual environments, such as RVM or RBENV, are supported.

Result Variables
^^^^^^^^^^^^^^^^

This module will set the following variables in your project:

``Ruby_FOUND``
  set to true if ruby was found successfully
``Ruby_EXECUTABLE``
  full path to the ruby binary
``Ruby_INCLUDE_DIRS``
  include dirs to be used when using the ruby library
``Ruby_LIBRARIES``
  .. versionadded:: 3.18
    libraries needed to use ruby from C.
``Ruby_VERSION``
  the version of ruby which was found, e.g. "3.2.6"
``Ruby_VERSION_MAJOR``
  Ruby major version.
``Ruby_VERSION_MINOR``
  Ruby minor version.
``Ruby_VERSION_PATCH``
  Ruby patch version.

.. versionchanged:: 3.18
  Previous versions of CMake used the ``RUBY_`` prefix for all variables.

.. deprecated:: 4.0
  The following variables are deprecated.  See policy :policy:`CMP0185`.

  ``RUBY_EXECUTABLE``
    same as ``Ruby_EXECUTABLE``.
  ``RUBY_INCLUDE_DIRS``
    same as ``Ruby_INCLUDE_DIRS``.
  ``RUBY_INCLUDE_PATH``
    same as ``Ruby_INCLUDE_DIRS``.
  ``RUBY_LIBRARY``
    same as ``Ruby_LIBRARY``.
  ``RUBY_VERSION``
    same as ``Ruby_VERSION``.
  ``RUBY_FOUND``
    same as ``Ruby_FOUND``.

Hints
^^^^^

``Ruby_FIND_VIRTUALENV``
  .. versionadded:: 3.18

  This variable defines the handling of virtual environments.
  It can be left empty or be set to one of the following values:

  * ``FIRST``: Virtual Ruby environments are searched for first,
               then the system Ruby installation.
               This is the default.
  * ``ONLY``: Only virtual environments are searched
  * ``STANDARD``: Only the system Ruby installation is searched.

  Virtual environments may be provided by:

  ``rvm``
    Requires that the ``MY_RUBY_HOME`` environment environment is defined.

  ``rbenv``
    Requires that ``rbenv`` is installed in ``~/.rbenv/bin``
    or that the ``RBENV_ROOT`` environment variable is defined.
#]=======================================================================]

cmake_policy(GET CMP0185 _Ruby_CMP0185)

if(NOT _Ruby_CMP0185 STREQUAL "NEW")
  # Backwards compatibility
  # Define camel case versions of input variables
  foreach (UPPER
           RUBY_EXECUTABLE
           RUBY_LIBRARY
           RUBY_INCLUDE_DIR
           RUBY_CONFIG_INCLUDE_DIR)
    if (DEFINED ${UPPER})
      string(REPLACE "RUBY_" "Ruby_" Camel ${UPPER})
      if (NOT DEFINED ${Camel})
        set(${Camel} ${${UPPER}})
      endif ()
    endif ()
  endforeach ()
endif()

#   Ruby_ARCHDIR=`$RUBY -r rbconfig -e 'printf("%s",Config::CONFIG@<:@"archdir"@:>@)'`
#   Ruby_SITEARCHDIR=`$RUBY -r rbconfig -e 'printf("%s",Config::CONFIG@<:@"sitearchdir"@:>@)'`
#   Ruby_SITEDIR=`$RUBY -r rbconfig -e 'printf("%s",Config::CONFIG@<:@"sitelibdir"@:>@)'`
#   Ruby_LIBDIR=`$RUBY -r rbconfig -e 'printf("%s",Config::CONFIG@<:@"libdir"@:>@)'`
#   Ruby_LIBRUBYARG=`$RUBY -r rbconfig -e 'printf("%s",Config::CONFIG@<:@"LIBRUBYARG_SHARED"@:>@)'`

# uncomment the following line to get debug output for this file
# set(CMAKE_MESSAGE_LOG_LEVEL DEBUG)

# Determine the list of possible names of the ruby executable depending
# on which version of ruby is required
set(_Ruby_POSSIBLE_EXECUTABLE_NAMES ruby)

# Set name of possible executables, ignoring the minor
# Eg:
# 3.2.6 => from ruby34 to ruby32 included
# 3.2   => from ruby34 to ruby32 included
# 3     => from ruby34 to ruby30 included
# empty => from ruby34 to ruby18 included
if (NOT Ruby_FIND_VERSION_EXACT)
  foreach (_ruby_version RANGE 34 18 -1)
    string(SUBSTRING "${_ruby_version}" 0 1 _ruby_major_version)
    string(SUBSTRING "${_ruby_version}" 1 1 _ruby_minor_version)
    # Append both rubyX.Y and rubyXY (eg: ruby2.7 ruby27)
    list(APPEND _Ruby_POSSIBLE_EXECUTABLE_NAMES ruby${_ruby_major_version}.${_ruby_minor_version} ruby${_ruby_major_version}${_ruby_minor_version})
  endforeach ()
endif ()

# Virtual environment handling
if (DEFINED Ruby_FIND_VIRTUALENV AND NOT Ruby_FIND_VIRTUALENV MATCHES "^(FIRST|ONLY|STANDARD)$")
  message(AUTHOR_WARNING "FindRuby: ${Ruby_FIND_VIRTUALENV}: invalid value for 'Ruby_FIND_VIRTUALENV'. 'FIRST', 'ONLY' or 'STANDARD' expected. 'FIRST' will be used instead.")
  set(Ruby_FIND_VIRTUALENV "FIRST")
elseif (NOT DEFINED Ruby_FIND_VIRTUALENV)
  # Default is to search for virtual environments first
  set(Ruby_FIND_VIRTUALENV "FIRST")
endif ()

function(_RUBY_VALIDATE_INTERPRETER result_var path)
  # Get the interpreter version
  execute_process(COMMAND "${path}" -e "puts RUBY_VERSION"
                  RESULT_VARIABLE result
                  OUTPUT_VARIABLE version
                  ERROR_QUIET
                  OUTPUT_STRIP_TRAILING_WHITESPACE)

  if (NOT result EQUAL 0)
    set(_Ruby_Interpreter_REASON_FAILURE "Cannot use the interpreter \"${path}\"")
    set(${result_var} FALSE PARENT_SCOPE)
    return()
  endif ()

  if (Ruby_FIND_VERSION)
    if (Ruby_FIND_VERSION_EXACT AND NOT version VERSION_EQUAL Ruby_FIND_VERSION)
      message(DEBUG "Incorrect Ruby found. Requested: ${Ruby_FIND_VERSION}. Found: ${version}. Path: \"${path}\"")
      set(${result_var} FALSE PARENT_SCOPE)
      return()
    elseif (version VERSION_LESS Ruby_FIND_VERSION)
      message(DEBUG "Ruby version is too old. Minimum: ${Ruby_FIND_VERSION}. Found: ${version}. Path: \"${path}\"")
      set(${result_var} FALSE PARENT_SCOPE)
      return()
    endif ()
  endif ()

  # Found valid Ruby interpreter!
  set(${result_var} TRUE PARENT_SCOPE)
endfunction()

function(_RUBY_CONFIG_VAR RBVAR OUTVAR)
  execute_process(COMMAND ${Ruby_EXECUTABLE} -r rbconfig -e "print RbConfig::CONFIG['${RBVAR}']"
                  RESULT_VARIABLE _Ruby_SUCCESS
                  OUTPUT_VARIABLE _Ruby_OUTPUT
                  ERROR_QUIET)
  if (_Ruby_SUCCESS OR _Ruby_OUTPUT STREQUAL "")
    execute_process(COMMAND ${Ruby_EXECUTABLE} -r rbconfig -e "print Config::CONFIG['${RBVAR}']"
                    RESULT_VARIABLE _Ruby_SUCCESS
                    OUTPUT_VARIABLE _Ruby_OUTPUT
                    ERROR_QUIET)
  endif ()
  set(${OUTVAR} "${_Ruby_OUTPUT}" PARENT_SCOPE)
endfunction()

####  Check RVM virtual environment ###
function(_RUBY_CHECK_RVM)
  if (NOT DEFINED ENV{MY_RUBY_HOME})
    return()
  endif ()

  find_program(Ruby_EXECUTABLE
               NAMES ${_Ruby_POSSIBLE_EXECUTABLE_NAMES}
               NAMES_PER_DIR
               PATHS ENV MY_RUBY_HOME
               PATH_SUFFIXES bin Scripts
               VALIDATOR _RUBY_VALIDATE_INTERPRETER
               NO_CMAKE_PATH
               NO_CMAKE_ENVIRONMENT_PATH
               NO_SYSTEM_ENVIRONMENT_PATH
               NO_CMAKE_SYSTEM_PATH)

  if (Ruby_EXECUTABLE)
    set(Ruby_ENV "RVM" CACHE INTERNAL "Ruby environment")
  endif ()
endfunction()

####  Check RBENV virtual environment ###
function(_RUBY_CHECK_RBENV)
  find_program(Ruby_RBENV_EXECUTABLE
               NAMES rbenv
               NAMES_PER_DIR
               PATHS "$ENV{HOME}/.rbenv/bin/rbenv" ENV RBENV_ROOT
               PATH_SUFFIXES bin Scripts
               NO_CACHE
               NO_CMAKE_PATH
               NO_CMAKE_ENVIRONMENT_PATH
               NO_CMAKE_SYSTEM_PATH)

  execute_process(COMMAND "${Ruby_RBENV_EXECUTABLE}" "which" "ruby"
                  RESULT_VARIABLE result
                  OUTPUT_VARIABLE ruby_exe
                  ERROR_QUIET
                  OUTPUT_STRIP_TRAILING_WHITESPACE)
  if (NOT result EQUAL 0)
    return()
  endif ()
  cmake_path(GET ruby_exe PARENT_PATH ruby_dir)

  find_program(Ruby_EXECUTABLE
               NAMES ruby
               NAMES_PER_DIR
               PATHS ${ruby_dir}
               VALIDATOR _RUBY_VALIDATE_INTERPRETER
               NO_DEFAULT_PATH)

  if (Ruby_EXECUTABLE)
    set(Ruby_ENV "RBENV" CACHE INTERNAL "Ruby environment")
  endif ()
endfunction()

####  Check system installed Ruby ###
function(_RUBY_CHECK_SYSTEM)
  find_program(Ruby_EXECUTABLE
               NAMES ${_Ruby_POSSIBLE_EXECUTABLE_NAMES}
               NAMES_PER_DIR
               VALIDATOR _RUBY_VALIDATE_INTERPRETER)

  if (Ruby_EXECUTABLE)
    set(Ruby_ENV "Standard" CACHE INTERNAL "Ruby environment")
  endif ()
endfunction()

# Find Ruby
if (NOT Ruby_EXECUTABLE AND Ruby_FIND_VIRTUALENV MATCHES "^(FIRST|ONLY)$")
  # First check for RVM virtual environments
  _RUBY_CHECK_RVM()
  # Second check for RBENV virtual environments
  if (NOT Ruby_EXECUTABLE)
    _RUBY_CHECK_RBENV()
  endif ()
endif ()

# Check for system installed Ruby
if (NOT Ruby_EXECUTABLE AND NOT Ruby_FIND_VIRTUALENV STREQUAL "ONLY")
  _RUBY_CHECK_SYSTEM()
endif ()

if (Ruby_EXECUTABLE AND NOT Ruby_EXECUTABLE STREQUAL "${_Ruby_EXECUTABLE_LAST_QUERIED}")
  # query the ruby version
  _RUBY_CONFIG_VAR("MAJOR" Ruby_VERSION_MAJOR)
  _RUBY_CONFIG_VAR("MINOR" Ruby_VERSION_MINOR)
  _RUBY_CONFIG_VAR("TEENY" Ruby_VERSION_PATCH)

  # query the different directories
  _RUBY_CONFIG_VAR("archdir" Ruby_ARCH_DIR)
  _RUBY_CONFIG_VAR("arch" Ruby_ARCH)
  _RUBY_CONFIG_VAR("rubyhdrdir" Ruby_HDR_DIR)
  _RUBY_CONFIG_VAR("rubyarchhdrdir" Ruby_ARCHHDR_DIR)
  _RUBY_CONFIG_VAR("libdir" _Ruby_POSSIBLE_LIB_DIR)
  _RUBY_CONFIG_VAR("rubylibdir" Ruby_RUBY_LIB_DIR)

  # site_ruby
  _RUBY_CONFIG_VAR("sitearchdir" Ruby_SITEARCH_DIR)
  _RUBY_CONFIG_VAR("sitelibdir" Ruby_SITELIB_DIR)

  # vendor_ruby available ?
  execute_process(COMMAND ${Ruby_EXECUTABLE} -r vendor-specific -e "print 'true'"
                  OUTPUT_VARIABLE Ruby_HAS_VENDOR_RUBY ERROR_QUIET)

  if (Ruby_HAS_VENDOR_RUBY)
    _RUBY_CONFIG_VAR("vendorlibdir" Ruby_VENDORLIB_DIR)
    _RUBY_CONFIG_VAR("vendorarchdir" Ruby_VENDORARCH_DIR)
  endif ()

  # save the results in the cache so we don't have to run ruby the next time again
  set(_Ruby_EXECUTABLE_LAST_QUERIED "${Ruby_EXECUTABLE}" CACHE INTERNAL "The ruby executable last queried for version and path info")
  set(Ruby_VERSION_MAJOR ${Ruby_VERSION_MAJOR} CACHE PATH "The Ruby major version" FORCE)
  set(Ruby_VERSION_MINOR ${Ruby_VERSION_MINOR} CACHE PATH "The Ruby minor version" FORCE)
  set(Ruby_VERSION_PATCH ${Ruby_VERSION_PATCH} CACHE PATH "The Ruby patch version" FORCE)
  set(Ruby_ARCH_DIR ${Ruby_ARCH_DIR} CACHE PATH "The Ruby arch dir" FORCE)
  set(Ruby_HDR_DIR ${Ruby_HDR_DIR} CACHE PATH "The Ruby header dir (1.9+)" FORCE)
  set(Ruby_ARCHHDR_DIR ${Ruby_ARCHHDR_DIR} CACHE PATH "The Ruby arch header dir (2.0+)" FORCE)
  set(_Ruby_POSSIBLE_LIB_DIR ${_Ruby_POSSIBLE_LIB_DIR} CACHE PATH "The Ruby lib dir" FORCE)
  set(Ruby_RUBY_LIB_DIR ${Ruby_RUBY_LIB_DIR} CACHE PATH "The Ruby ruby-lib dir" FORCE)
  set(Ruby_SITEARCH_DIR ${Ruby_SITEARCH_DIR} CACHE PATH "The Ruby site arch dir" FORCE)
  set(Ruby_SITELIB_DIR ${Ruby_SITELIB_DIR} CACHE PATH "The Ruby site lib dir" FORCE)
  set(Ruby_HAS_VENDOR_RUBY ${Ruby_HAS_VENDOR_RUBY} CACHE BOOL "Vendor Ruby is available" FORCE)
  set(Ruby_VENDORARCH_DIR ${Ruby_VENDORARCH_DIR} CACHE PATH "The Ruby vendor arch dir" FORCE)
  set(Ruby_VENDORLIB_DIR ${Ruby_VENDORLIB_DIR} CACHE PATH "The Ruby vendor lib dir" FORCE)

  mark_as_advanced(
      Ruby_ARCH_DIR
      Ruby_ARCH
      Ruby_HDR_DIR
      Ruby_ARCHHDR_DIR
      _Ruby_POSSIBLE_LIB_DIR
      Ruby_RUBY_LIB_DIR
      Ruby_SITEARCH_DIR
      Ruby_SITELIB_DIR
      Ruby_HAS_VENDOR_RUBY
      Ruby_VENDORARCH_DIR
      Ruby_VENDORLIB_DIR
      Ruby_VERSION_MAJOR
      Ruby_VERSION_MINOR
      Ruby_VERSION_PATCH
  )
endif ()

# In case Ruby_EXECUTABLE could not be executed (e.g. cross compiling)
# try to detect which version we found. This is not too good.
if (Ruby_EXECUTABLE AND NOT Ruby_VERSION_MAJOR)
  # by default assume 1.8.0
  set(Ruby_VERSION_MAJOR 1)
  set(Ruby_VERSION_MINOR 8)
  set(Ruby_VERSION_PATCH 0)
  # check whether we found 1.9.x
  if (${Ruby_EXECUTABLE} MATCHES "ruby1\\.?9")
    set(Ruby_VERSION_MAJOR 1)
    set(Ruby_VERSION_MINOR 9)
  endif ()
  # check whether we found 2.[0-7].x
  if (${Ruby_EXECUTABLE} MATCHES "ruby2")
    set(Ruby_VERSION_MAJOR 2)
    string(REGEX_REPLACE ${Ruby_EXECUTABLE} "ruby2\\.?([0-7])" "\\1" Ruby_VERSION_MINOR)
  endif ()
  # check whether we found 3.[0-1].x
  if (${Ruby_EXECUTABLE} MATCHES "ruby3")
    set(Ruby_VERSION_MAJOR 3)
    string(REGEX_REPLACE ${Ruby_EXECUTABLE} "ruby3\\.?([0-1])" "\\1" Ruby_VERSION_MINOR)
  endif ()
endif ()

if (Ruby_VERSION_MAJOR)
  set(Ruby_VERSION "${Ruby_VERSION_MAJOR}.${Ruby_VERSION_MINOR}.${Ruby_VERSION_PATCH}")
  set(_Ruby_VERSION_SHORT "${Ruby_VERSION_MAJOR}.${Ruby_VERSION_MINOR}")
  set(_Ruby_VERSION_SHORT_NODOT "${Ruby_VERSION_MAJOR}${Ruby_VERSION_MINOR}")
  set(_Ruby_NODOT_VERSION "${Ruby_VERSION_MAJOR}${Ruby_VERSION_MINOR}${Ruby_VERSION_PATCH}")
  set(_Ruby_NODOT_VERSION_ZERO_PATCH "${Ruby_VERSION_MAJOR}${Ruby_VERSION_MINOR}0")
endif ()

# FIXME: Currently we require both the interpreter and development components to be found
# in order to use either.  See issue #20474.
find_path(Ruby_INCLUDE_DIR
          NAMES ruby.h
          HINTS
          ${Ruby_HDR_DIR}
          ${Ruby_ARCH_DIR}
          /usr/lib/ruby/${_Ruby_VERSION_SHORT}/i586-linux-gnu/
)

set(Ruby_INCLUDE_DIRS ${Ruby_INCLUDE_DIR})

# if ruby > 1.8 is required or if ruby > 1.8 was found, search for the config.h dir
if (Ruby_FIND_VERSION VERSION_GREATER_EQUAL "1.9" OR Ruby_VERSION VERSION_GREATER_EQUAL "1.9" OR Ruby_HDR_DIR)
  find_path(Ruby_CONFIG_INCLUDE_DIR
            NAMES ruby/config.h config.h
            HINTS
            ${Ruby_HDR_DIR}/${Ruby_ARCH}
            ${Ruby_ARCH_DIR}
            ${Ruby_ARCHHDR_DIR}
  )

  set(Ruby_INCLUDE_DIRS ${Ruby_INCLUDE_DIRS} ${Ruby_CONFIG_INCLUDE_DIR})
endif ()

# Determine the list of possible names for the ruby library
set(_Ruby_POSSIBLE_LIB_NAMES ruby ruby-static ruby${_Ruby_VERSION_SHORT} ruby${_Ruby_VERSION_SHORT_NODOT} ruby${_Ruby_NODOT_VERSION} ruby-${_Ruby_VERSION_SHORT} ruby-${Ruby_VERSION})

if (WIN32)
  set(_Ruby_POSSIBLE_MSVC_RUNTIMES "ucrt;msvcrt;vcruntime140;vcruntime140_1")
  if (MSVC_TOOLSET_VERSION)
    list(APPEND _Ruby_POSSIBLE_MSVC_RUNTIMES "msvcr${MSVC_TOOLSET_VERSION}")
  else ()
    list(APPEND _Ruby_POSSIBLE_MSVC_RUNTIMES "msvcr")
  endif ()

  set(_Ruby_POSSIBLE_VERSION_SUFFICES "${_Ruby_NODOT_VERSION};${_Ruby_NODOT_VERSION_ZERO_PATCH}")

  if (CMAKE_SIZEOF_VOID_P EQUAL 8)
    set(_Ruby_POSSIBLE_ARCH_PREFIXS "libx64-;x64-")
  else ()
    set(_Ruby_POSSIBLE_ARCH_PREFIXS "lib")
  endif ()

  foreach (_Ruby_MSVC_RUNTIME ${_Ruby_POSSIBLE_MSVC_RUNTIMES})
    foreach (_Ruby_VERSION_SUFFIX ${_Ruby_POSSIBLE_VERSION_SUFFICES})
      foreach (_Ruby_ARCH_PREFIX ${_Ruby_POSSIBLE_ARCH_PREFIXS})
        list(APPEND _Ruby_POSSIBLE_LIB_NAMES
             "${_Ruby_ARCH_PREFIX}${_Ruby_MSVC_RUNTIME}-ruby${_Ruby_VERSION_SUFFIX}"
             "${_Ruby_ARCH_PREFIX}${_Ruby_MSVC_RUNTIME}-ruby${_Ruby_VERSION_SUFFIX}-static")
      endforeach ()
    endforeach ()
  endforeach ()
endif ()

find_library(Ruby_LIBRARY NAMES ${_Ruby_POSSIBLE_LIB_NAMES} HINTS ${_Ruby_POSSIBLE_LIB_DIR})

set(_Ruby_REQUIRED_VARS Ruby_EXECUTABLE Ruby_INCLUDE_DIR Ruby_LIBRARY)
if (_Ruby_VERSION_SHORT_NODOT GREATER 18)
  list(APPEND _Ruby_REQUIRED_VARS Ruby_CONFIG_INCLUDE_DIR)
endif ()

message(DEBUG "--------FindRuby.cmake debug------------")
message(DEBUG "_Ruby_POSSIBLE_EXECUTABLE_NAMES: ${_Ruby_POSSIBLE_EXECUTABLE_NAMES}")
message(DEBUG "_Ruby_POSSIBLE_LIB_DIR: ${_Ruby_POSSIBLE_LIB_DIR}")
message(DEBUG "_Ruby_POSSIBLE_LIB_NAMES: ${_Ruby_POSSIBLE_LIB_NAMES}")
message(DEBUG "Ruby_FIND_VIRTUALENV=${Ruby_FIND_VIRTUALENV}")
message(DEBUG "Ruby_ENV: ${Ruby_ENV}")
message(DEBUG "Found Ruby_VERSION: \"${Ruby_VERSION}\"")
message(DEBUG "Ruby_EXECUTABLE: ${Ruby_EXECUTABLE}")
message(DEBUG "Ruby_LIBRARY: ${Ruby_LIBRARY}")
message(DEBUG "Ruby_INCLUDE_DIR: ${Ruby_INCLUDE_DIR}")
message(DEBUG "Ruby_CONFIG_INCLUDE_DIR: ${Ruby_CONFIG_INCLUDE_DIR}")
message(DEBUG "Ruby_HDR_DIR: ${Ruby_HDR_DIR}")
message(DEBUG "Ruby_ARCH_DIR: ${Ruby_ARCH_DIR}")
message(DEBUG "--------------------")

include(FindPackageHandleStandardArgs)
find_package_handle_standard_args(Ruby REQUIRED_VARS ${_Ruby_REQUIRED_VARS}
                                  VERSION_VAR Ruby_VERSION)

if (Ruby_FOUND)
  set(Ruby_LIBRARIES ${Ruby_LIBRARY})
endif ()

mark_as_advanced(
    Ruby_EXECUTABLE
    Ruby_LIBRARY
    Ruby_INCLUDE_DIR
    Ruby_CONFIG_INCLUDE_DIR
)

if(NOT _Ruby_CMP0185 STREQUAL "NEW")
  # Set some variables for compatibility with previous version of this file (no need to provide a CamelCase version of that...)
  set(RUBY_POSSIBLE_LIB_PATH ${_Ruby_POSSIBLE_LIB_DIR})
  set(RUBY_RUBY_LIB_PATH ${Ruby_RUBY_LIB_DIR})
  set(RUBY_INCLUDE_PATH ${Ruby_INCLUDE_DIRS})

  # Backwards compatibility
  # Define upper case versions of output variables
  foreach (Camel
           Ruby_EXECUTABLE
           Ruby_INCLUDE_DIRS
           Ruby_LIBRARY
           Ruby_VERSION
           Ruby_VERSION_MAJOR
           Ruby_VERSION_MINOR
           Ruby_VERSION_PATCH

           Ruby_ARCH_DIR
           Ruby_ARCH
           Ruby_HDR_DIR
           Ruby_ARCHHDR_DIR
           Ruby_RUBY_LIB_DIR
           Ruby_SITEARCH_DIR
           Ruby_SITELIB_DIR
           Ruby_HAS_VENDOR_RUBY
           Ruby_VENDORARCH_DIR
           Ruby_VENDORLIB_DIR)
    string(TOUPPER ${Camel} UPPER)
    set(${UPPER} ${${Camel}})
  endforeach ()
endif()