Closed
Description
Bug report
As I was investigating why the scikit-image CI build using PYTHONOPTIMIZE=2 was failing, I identified the following problem:
when using export PYTHONOPTIMIZE=2, the following code results in an AttributeError
In [1]: from mpl_toolkits.axes_grid1 import make_axes_locatable
---------------------------------------------------------------------------
AttributeError Traceback (most recent call last)
<ipython-input-1-2bee72614a62> in <module>
----> 1 from mpl_toolkits.axes_grid1 import make_axes_locatable
~/sandbox/venv_mpl/lib/python3.7/site-packages/mpl_toolkits/axes_grid1/__init__.py in <module>
----> 1 from . import axes_size as Size
2 from .axes_divider import Divider, SubplotDivider, make_axes_locatable
3 from .axes_grid import Grid, ImageGrid, AxesGrid
4
5 from .parasite_axes import host_subplot, host_axes
~/sandbox/venv_mpl/lib/python3.7/site-packages/mpl_toolkits/axes_grid1/axes_size.py in <module>
13
14 from matplotlib import cbook
---> 15 from matplotlib.axes import Axes
16
17
~/sandbox/venv_mpl/lib/python3.7/site-packages/matplotlib/axes/__init__.py in <module>
----> 1 from ._subplots import *
2 from ._axes import *
~/sandbox/venv_mpl/lib/python3.7/site-packages/matplotlib/axes/_subplots.py in <module>
4 from matplotlib import cbook, docstring
5 import matplotlib.artist as martist
----> 6 from matplotlib.axes._axes import Axes
7 from matplotlib.gridspec import GridSpec, SubplotSpec
8 import matplotlib._layoutbox as layoutbox
~/sandbox/venv_mpl/lib/python3.7/site-packages/matplotlib/axes/_axes.py in <module>
69
70
---> 71 class Axes(_AxesBase):
72 """
73 The `Axes` contains most of the figure elements: `~.axis.Axis`,
~/sandbox/venv_mpl/lib/python3.7/site-packages/matplotlib/axes/_axes.py in Axes()
5303 where=where, interpolate=interpolate, step=step, **kwargs)
5304
-> 5305 fill_between.__doc__ = _fill_between_x_or_y.__doc__.format(
5306 dir="horizontal", ind="x", dep="y")
5307 fill_between = _preprocess_data(
AttributeError: 'NoneType' object has no attribute 'format'using matplotlib 3.3.0 in a fresh environment.
The reason is that docstrings are stripped from the code when using PYTHONOPTIMIZE with 1 or 2, hence fill_between.__doc__ is None. One solution could be to put this line in a try/except block.