[Bug]: Infinite loop when there is single double quote in matplotlibrc #22636
Description
Bug summary
This code https://github.com/timhoffm/matplotlib/blob/7c378a8f3f30ce57c874a851f3af8af58f1ffdf6/lib/matplotlib/cbook/__init__.py#L403-L415 on the main branch (not released yet) falls into an infinite loop when there is only one double quotation because when s.find('"', quote_pos + 1) == -1 pos == 0
context:
Code for reproduction
from pathlib import Path
import matplotlib.pyplot as plt
Path("./test.mplstyle").write_text('grid.color: "aa')
plt.style.use("./test.mplstyle")Actual outcome
The program doesn't exit.
Expected outcome
Show an error or set '"aa'.
Additional information
No response
Operating system
No response
Matplotlib Version
3.6.0.dev1816+gb9ae51ca8c.d20220311
Matplotlib Backend
No response
Python version
Python 3.10.0
Jupyter version
No response
Installation
No response