old_contents: ##############################################################################
  # Copyright (c) 2013-2018, Lawrence Livermore National Security, LLC.
  # Produced at the Lawrence Livermore National Laboratory.
  #
  # This file is part of Spack.
  # Created by Todd Gamblin, tgamblin@llnl.gov, All rights reserved.
  # LLNL-CODE-647188
  #
  # For details, see https://github.com/spack/spack
  # Please also see the NOTICE and LICENSE files for our notice and the LGPL.
  #
  # This program is free software; you can redistribute it and/or modify
  # it under the terms of the GNU Lesser General Public License (as
  # published by the Free Software Foundation) version 2.1, February 1999.
  #
  # 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 terms and
  # conditions of the GNU Lesser General Public License for more details.
  #
  # You should have received a copy of the GNU Lesser General Public
  # License along with this program; if not, write to the Free Software
  # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  ##############################################################################
  import platform as py_platform
  
  from spack.architecture import OperatingSystem
  from spack.version import Version
  
  
  # FIXME: store versions inside OperatingSystem as a Version instead of string
  def macos_version():
      """temporary workaround to return a macOS version as a Version object
      """
      return Version('.'.join(py_platform.mac_ver()[0].split('.')[:2]))
  
  
  class MacOs(OperatingSystem):
      """This class represents the macOS operating system. This will be
      auto detected using the python platform.mac_ver. The macOS
      platform will be represented using the major version operating
      system name, i.e el capitan, yosemite...etc.
      """
  
      def __init__(self):
          """ Autodetects the mac version from a dictionary. Goes back as
              far as 10.6 snowleopard. If the user has an older mac then
              the version will just be a generic mac_os.
          """
          mac_releases = {'10.6': "snowleopard",
                          "10.7": "lion",
                          "10.8": "mountainlion",
                          "10.9": "mavericks",
                          "10.10": "yosemite",
                          "10.11": "elcapitan",
                          "10.12": "sierra",
                          "10.13": "highsierra"}
  
          mac_ver = '.'.join(py_platform.mac_ver()[0].split('.')[:2])
          name = mac_releases.get(mac_ver, "macos")
          super(MacOs, self).__init__(name, mac_ver)
  
      def __str__(self):
          return self.name
  
new_contents: ##############################################################################
  # Copyright (c) 2013-2018, Lawrence Livermore National Security, LLC.
  # Produced at the Lawrence Livermore National Laboratory.
  #
  # This file is part of Spack.
  # Created by Todd Gamblin, tgamblin@llnl.gov, All rights reserved.
  # LLNL-CODE-647188
  #
  # For details, see https://github.com/spack/spack
  # Please also see the NOTICE and LICENSE files for our notice and the LGPL.
  #
  # This program is free software; you can redistribute it and/or modify
  # it under the terms of the GNU Lesser General Public License (as
  # published by the Free Software Foundation) version 2.1, February 1999.
  #
  # 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 terms and
  # conditions of the GNU Lesser General Public License for more details.
  #
  # You should have received a copy of the GNU Lesser General Public
  # License along with this program; if not, write to the Free Software
  # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  ##############################################################################
  import platform as py_platform
  
  from spack.architecture import OperatingSystem
  from spack.version import Version
  
  
  # FIXME: store versions inside OperatingSystem as a Version instead of string
  def macos_version():
      """temporary workaround to return a macOS version as a Version object
      """
      return Version('.'.join(py_platform.mac_ver()[0].split('.')[:2]))
  
  
  class MacOs(OperatingSystem):
      """This class represents the macOS operating system. This will be
      auto detected using the python platform.mac_ver. The macOS
      platform will be represented using the major version operating
      system name, i.e el capitan, yosemite...etc.
      """
  
      def __init__(self):
          """ Autodetects the mac version from a dictionary. Goes back as
              far as 10.6 snowleopard. If the user has an older mac then
              the version will just be a generic mac_os.
          """
          mac_releases = {'10.6': "snowleopard",
                          "10.7": "lion",
                          "10.8": "mountainlion",
                          "10.9": "mavericks",
                          "10.10": "yosemite",
                          "10.11": "elcapitan",
                          "10.12": "sierra",
                          "10.13": "highsierra",
                          "10.14": "mojave"}
  
          mac_ver = '.'.join(py_platform.mac_ver()[0].split('.')[:2])
          name = mac_releases.get(mac_ver, "macos")
          super(MacOs, self).__init__(name, mac_ver)
  
      def __str__(self):
          return self.name
  
subject: add mojave (#9322)