old_contents: #!/usr/bin/env python3
  
  import os
  import subprocess
  
  install_prefix = os.environ['MESON_INSTALL_PREFIX']
  icondir = os.path.join(install_prefix, 'share', 'icons', 'hicolor')
  schemadir = os.path.join(install_prefix, 'share', 'glib-2.0', 'schemas')
  
  if not os.environ.get('DESTDIR'):
    print('Update icon cache...')
    subprocess.call(['gtk-update-icon-cache', '-f', '-t', icondir])
  
    print('Compiling gsettings schemas...')
    subprocess.call(['glib-compile-schemas', schemadir])
  
new_contents: #!/usr/bin/env python3
  
  import os
  import subprocess
  
  install_prefix = os.environ['MESON_INSTALL_PREFIX']
  icondir = os.path.join(install_prefix, 'share', 'icons', 'hicolor')
  schemadir = os.path.join(install_prefix, 'share', 'glib-2.0', 'schemas')
  
  print('Update xdg dirs...')
  subprocess.call(['xdg-user-dirs-update']);
  
  if not os.environ.get('DESTDIR'):
    print('Update icon cache...')
    subprocess.call(['gtk-update-icon-cache', '-f', '-t', icondir])
  
    print('Compiling gsettings schemas...')
    subprocess.call(['glib-compile-schemas', schemadir])
  
subject: add to post install script xdg-user-dirs-update