import os

from pathlib import Path

from tempfile import TemporaryDirectory

import pytest

from matplotlib.testing import subprocess_run_for_testing

nbformat = pytest.importorskip('nbformat')

pytest.importorskip('nbconvert')

pytest.importorskip('ipykernel')

# From https://blog.thedataincubator.com/2016/06/testing-jupyter-notebooks/

def test_ipynb():

nb_path = Path(__file__).parent / 'data/test_nbagg_01.ipynb'

with TemporaryDirectory() as tmpdir:

out_path = Path(tmpdir, "out.ipynb")

subprocess_run_for_testing(

["jupyter", "nbconvert", "--to", "notebook",

"--execute", "--ExecutePreprocessor.timeout=500",

"--output", str(out_path), str(nb_path)],

env={**os.environ, "IPYTHONDIR": tmpdir},

check=True)

with out_path.open() as out:

nb = nbformat.read(out, nbformat.current_nbformat)

errors = [output for cell in nb.cells for output in cell.get("outputs", [])

if output.output_type == "error"]

assert not errors

import IPython

if IPython.version_info[:2] >= (8, 24):

expected_backend = "notebook"

else:

# This code can be removed when Python 3.12, the latest version supported by

# IPython < 8.24, reaches end-of-life in late 2028.

expected_backend = "nbAgg"

backend_outputs = nb.cells[2]["outputs"]

assert backend_outputs[0]["data"]["text/plain"] == f"'{expected_backend}'"