With python-dbusmock you can provide mocks for arbitrary D-BUS services for your test suites or if you want to reproduce a bug.

However, when writing actual tests for gnome-settings-daemon etc. I noticed that it is rather cumbersome to always have to set up the “skeleton” of common services such as UPower. python-dbusmock 0.2 now introduces the concept of “templates” which provide those skeletons for common standard services so that your code only needs to set up the particular properties and specific D-BUS objects that you need. These templates can be parameterized for common customizations, and they can provide additional convenience methods on the org.freedesktop.DBus.Mock interface to provide more abstract functionality like “add a battery”.

So if you want to pretend you have one AC and a half-charged battery, you can now simply do

  def setUp(self):
     (self.p_mock, self.obj_upower) = self.spawn_server_template('upower', {})

  def test_ac_bat(self):
     self.obj_upower.AddAC('mock_AC', 'Mock AC')
     self.obj_upower.AddChargingBattery('mock_BAT', 'Mock Battery', 50.0, 1200)

Or, if your code is not in Python, use the CLI/D-BUS interface, like in shell:

  # start a fake system bus
  eval `dbus-launch`
  export DBUS_SYSTEM_BUS_ADDRESS=$DBUS_SESSION_BUS_ADDRESS

  # start mock upower on the fake bus
  python3 -m dbusmock --template upower &

  # add devices
  gdbus call --system -d org.freedesktop.UPower -o /org/freedesktop/UPower \
      -m org.freedesktop.DBus.Mock.AddAC mock_ac 'Mock AC'
  gdbus call --system -d org.freedesktop.UPower -o /org/freedesktop/UPower \
      -m org.freedesktop.DBus.Mock.AddChargingBattery mock_bat 'Mock Bat' 50.0 1200

In both cases upower --dump or gnome-power-statistics will show you the expected devices (of course you need to run that within the environment of the fake $DBUS_SYSTEM_BUS_ADDRESS, or run the mock on the real system bus as root).

Iftikhar Ahmad contributed a template for NetworkManager, which allows you to easily set up ethernet and wifi devices and wifi access points. See pydoc3 dbusmock.templates.networkmanager for details and the test cases for how this looks like in practice.

I just released python-dbusmock 0.2.1 and uploaded the new version to Debian experimental. I will sync it into Ubuntu Raring in a few hours.