Bug report

Bug summary

Because Spine is mostly written for rectilinear axes, calling some seemingly harmless methods on polar spines can completely mess up their positioning.

Code for reproduction

from pylab import *
polar()
print(gca().spines["polar"].get_position())
show()

or

from pylab import *; polar(); print(gca().spines["polar"].get_spine_transform())

Actual outcome

Expected outcome

The spine stays correct, or at least the get_foo getter raises an exception.

Matplotlib version

• Operating system: linux
• Matplotlib version: head
• Matplotlib backend (print(matplotlib.get_backend())): qt5agg
• Python version: 38
• Jupyter version (if applicable):
• Other libraries: