Transitions created for animatable properties use the name of the property itself, for instance the code below:
clutter_actor_set_easing_duration (actor, 1000);
clutter_actor_set_rotation (actor, CLUTTER_Y_AXIS, 360.0, x, y, z);
transition = clutter_actor_get_transition (actor, "rotation-angle-y");
g_signal_connect (transition, "stopped",
will call the `on_transition_stopped` callback when the transition is finished.
If you just want to get notifications of the completion of a transition, you should use the transition_stopped signal, using the transition name as the signal detail.
the name of the transition
a Transition, or