1 error in tests preventing all tests from running: _tkinter.TclError: no display name and no $DISPLAY environment variable

[yurivict]

Describe the bug

========================================================================================== ERRORS ===========================================================================================
_____________________________________________________________ ERROR collecting arviz/tests/base_tests/test_plots_matplotlib.py ______________________________________________________________
arviz/tests/base_tests/test_plots_matplotlib.py:139: in <module>
    {"ax": plt.subplots(6, 3)[1]},
/usr/local/lib/python3.11/site-packages/matplotlib/pyplot.py:1598: in subplots
    fig = figure(**fig_kw)
/usr/local/lib/python3.11/site-packages/matplotlib/pyplot.py:934: in figure
    manager = new_figure_manager(
/usr/local/lib/python3.11/site-packages/matplotlib/pyplot.py:465: in new_figure_manager
    return _get_backend_mod().new_figure_manager(*args, **kwargs)
/usr/local/lib/python3.11/site-packages/matplotlib/backend_bases.py:3396: in new_figure_manager
    return cls.new_figure_manager_given_figure(num, fig)
/usr/local/lib/python3.11/site-packages/matplotlib/backend_bases.py:3401: in new_figure_manager_given_figure
    return cls.FigureCanvas.new_manager(figure, num)
/usr/local/lib/python3.11/site-packages/matplotlib/backend_bases.py:1785: in new_manager
    return cls.manager_class.create_with_canvas(cls, figure, num)
/usr/local/lib/python3.11/site-packages/matplotlib/backends/_backend_tk.py:486: in create_with_canvas
    window = tk.Tk(className="matplotlib")
/usr/local/lib/python3.11/tkinter/__init__.py:2345: in __init__
    self.tk = _tkinter.create(screenName, baseName, className, interactive, wantobjects, useTk, sync, use)
E   _tkinter.TclError: no display name and no $DISPLAY environment variable
================================================================================== short test summary info ==================================================================================
SKIPPED [1] arviz/tests/helpers.py:658: could not import 'bokeh.plotting': No module named 'bokeh'
SKIPPED [1] arviz/tests/external_tests/test_data_beanmachine.py:14: Ignore beanmachine tests until it supports pytorch 2
SKIPPED [1] arviz/tests/helpers.py:658: could not import 'emcee': No module named 'emcee'
SKIPPED [1] arviz/tests/helpers.py:658: could not import 'jax': jax requires jaxlib to be installed. See https://github.com/google/jax#installation for installation instructions.
SKIPPED [1] arviz/tests/external_tests/test_data_pyjags.py:16: Uses deprecated numpy C-api
SKIPPED [1] arviz/tests/helpers.py:658: could not import 'pyro': No module named 'pyro'
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Interrupted: 1 error during collection !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
================================================================================ 6 skipped, 1 error in 8.52s ================================================================================

Version: 0.19.0
Python 3.11
FreeBSD 14.1

[OriolAbril]

From the error it seems related to general matplotlib configuration, not ArviZ specific. Can you run this other test in the same env?

import matplotlib.pyplot as plt

def test_create_subplots():
    fig, ax = plt.subplots(2, 2)
    assert ax.shape == (2, 2)

def test_plot():
    fig, ax = plt.subplots()
    lines = ax.plot([0, 1], [0, 1])
    assert len(lines) == 1