[Bf-python] Key/KeyBlock API bug?

[Ken Hughes]

I started to fix a bug from the tracker related to the Keys module, but 
after staring at the BPy code and blender keys code I need a fresh set 
of brains to make sure I understand what I'm seeing.

The keyblock.getData() method is supposed to return one of three data 
types, depending on the key type: and NMVert for mesh data, a BezTriple 
for a curve, and a BPoint (four floats) for lattices.  After looking 
through the key code, though, I *think* I see two problems:

(1) lattices store 3 floats for the x/y/z coordinates of the lattice 
points, but getData() is reading 4 floats (see key_to_latt() function)
(2) curves can be NURBS or Bezier, so you can't just return BezTriples 
(look at key_to_curve() function, for example)

The first would be easy to fix, but the second not so much.  I can't see 
anything in the key structure which differentiates NURBS and Bezier; it 
seems it's based on the curve data itself (again see key_to_curve()). 
So it looks like we need to search the list of curves to see who is 
linked to that key to know how to interpret the data.

Ken