2005-10-29 Robert McQueen <robot101@debian.org>
* python/service.py: Major changes to allow multiple inheritance
from classes that define D-Bus interfaces:
1. Create a new Interface class which is the parent class of
Object, and make the ObjectType metaclass into InterfaceType.
2. Patch written with Rob Taylor to replace use of method_vtable
with code that walks the class's __MRO__ (method resolution order)
to behave like Python does when invoking methods and allow
overriding as you'd expect. Code is quite tricky because
we have to find two methods, the one to invoke which has the
right name and isn't decorated with the /wrong/ interface,
and the one to pick up the signatures from which is decorated
with the right interface.
The same caveats apply as to normal multiple inheritance -
this has undefined behaviour if you try and inherit from two
classes that define a method with the same name but are
decorated with different interfaces. You should decorate
your overriding method with the interface you want.
3. Replace grungy introspection XML generation code in the metaclass
with dictionaries that cope correctly with multiple inheritance
and the overriding of methods. This also uses the signature
decorations to provide correct introspection data, including
the debut appearance of the types of your return values. :D
* test/python/test-client.py, test/python/test-service.py: Add a test
case to try invoking an method that overrides one inherited from a
D-Bus interface class.