new_contents: import os
  from spack import *
  
  class Gflags(Package):
      """The gflags package contains a C++ library that implements
      commandline flags processing. It includes built-in support for
      standard types such as string and the ability to define flags
      in the source file in which they are used. Online documentation
      available at: https://gflags.github.io/gflags/"""
  
      homepage = "https://gflags.github.io/gflags"
      url      = "https://github.com/gflags/gflags/archive/v2.1.2.tar.gz"
  
      version('2.1.2', 'ac432de923f9de1e9780b5254884599f')
  
      def install(self, spec, prefix):
          cmake("-DCMAKE_INSTALL_PREFIX=" + prefix,
                "-DBUILD_SHARED_LIBS=ON")
          make()
          make("test")
          make("install")
  
subject: add gflags package