hub/venv/lib/python3.7/site-packages/matplotlib/tests/test_png.py

68 lines
1.7 KiB
Python

from io import BytesIO
import glob
import os
from pathlib import Path
import numpy as np
import pytest
from matplotlib.testing.decorators import image_comparison
from matplotlib import pyplot as plt
import matplotlib.cm as cm
@image_comparison(['pngsuite.png'], tol=0.03)
def test_pngsuite():
dirname = os.path.join(
os.path.dirname(__file__),
'baseline_images',
'pngsuite')
files = sorted(glob.iglob(os.path.join(dirname, 'basn*.png')))
plt.figure(figsize=(len(files), 2))
for i, fname in enumerate(files):
data = plt.imread(fname)
cmap = None # use default colormap
if data.ndim == 2:
# keep grayscale images gray
cmap = cm.gray
plt.imshow(data, extent=[i, i + 1, 0, 1], cmap=cmap)
plt.gca().patch.set_facecolor("#ddffff")
plt.gca().set_xlim(0, len(files))
def test_imread_png_uint16():
from matplotlib import _png
with (Path(__file__).parent
/ 'baseline_images/test_png/uint16.png').open('rb') as file:
img = _png.read_png_int(file)
assert (img.dtype == np.uint16)
assert np.sum(img.flatten()) == 134184960
def test_truncated_file(tmpdir):
d = tmpdir.mkdir('test')
fname = str(d.join('test.png'))
fname_t = str(d.join('test_truncated.png'))
plt.savefig(fname)
with open(fname, 'rb') as fin:
buf = fin.read()
with open(fname_t, 'wb') as fout:
fout.write(buf[:20])
with pytest.raises(Exception):
plt.imread(fname_t)
def test_truncated_buffer():
b = BytesIO()
plt.savefig(b)
b.seek(0)
b2 = BytesIO(b.read(20))
b2.seek(0)
with pytest.raises(Exception):
plt.imread(b2)