A little helper function to toggle Subscriber on and off

toggleSubscriber.py

from mojo.subscriber import *


def toggleSubscriberClass(SubscriberClass, register_function):
    """
    Will register a SubscriberClass with the suplied register_function if that SubscriberClass is not already registered.
    Will unregister a SubscriberClass with the corresponding unregister_function if that SubscriberClass is already registered.

    Usage:
    considering the Neighbours.py example in the Robofont documentation

    if __name__ == '__main__':
        toggleSubscriberClass(Neighbours, registerGlyphEditorSubscriber)
    """

    register_function_map = {
        registerRoboFontSubscriber: unregisterRoboFontSubscriber,
        registerFontOverviewSubscriber: unregisterFontOverviewSubscriber,
        registerGlyphEditorSubscriber: unregisterGlyphEditorSubscriber,
        registerSpaceCenterSubscriber: unregisterSpaceCenterSubscriber,
        registerCurrentFontSubscriber: unregisterCurrentFontSubscriber,
        registerCurrentGlyphSubscriber: unregisterCurrentGlyphSubscriber,
    }
    assert register_function in register_function_map, f"{register_function} appears not to be a supported Subscriber registration method"

    registered_subscribers = listRegisteredSubscribers(SubscriberClassName=SubscriberClass.__name__)
    if len(registered_subscribers) > 0:
        unregister_function = register_function_map.get(register_function)
        for target_subscriber in registered_subscribers:
            unregister_function(target_subscriber)
        print(f"Toggle {SubscriberClass.__name__} off")
    else:
        register_function(SubscriberClass)
        print(f"Toggle {SubscriberClass.__name__} on")