When running `pyplot.spy` I ran into the following error:
AttributeError: 'BlendedGenericTransform' object has no attribute '_interpolation_steps'
Just from pattern matching (I have no idea what's going on in the code), I noticed that _interpolation_steps was usually called from a Path object, not a Transform object, so I tried switching the call (see diff below), which seems to work for me. Since this was a recent addition (r7130), I figure this was just a typo.
--- lib/matplotlib/transforms.py (revision 7133)
+++ lib/matplotlib/transforms.py (working copy)
@@ -1145,7 +1145,7 @@
return Path(self.transform_non_affine(path.vertices), path.codes,
def transform_angles(self, angles, pts, radians=False, pushoff=1e-5):