Fixed database typo and removed unnecessary class identifier.

venv/Lib/site-packages/skimage/io/tests/test_io.py

@@ -0,0 +1,104 @@
+import os
+import tempfile
+
+import numpy as np
+from skimage import io
+
+from skimage._shared import testing
+from skimage._shared.testing import assert_array_equal
+from skimage._shared.testing import fetch
+from skimage.data import data_dir
+
+
+one_by_one_jpeg = (
+    b'\xff\xd8\xff\xe0\x00\x10JFIF\x00\x01\x01\x00\x00\x01'
+    b'\x00\x01\x00\x00\xff\xdb\x00C\x00\x03\x02\x02\x02\x02'
+    b'\x02\x03\x02\x02\x02\x03\x03\x03\x03\x04\x06\x04\x04'
+    b'\x04\x04\x04\x08\x06\x06\x05\x06\t\x08\n\n\t\x08\t\t'
+    b'\n\x0c\x0f\x0c\n\x0b\x0e\x0b\t\t\r\x11\r\x0e\x0f\x10'
+    b'\x10\x11\x10\n\x0c\x12\x13\x12\x10\x13\x0f\x10\x10'
+    b'\x10\xff\xc0\x00\x0b\x08\x00\x01\x00\x01\x01\x01\x11'
+    b'\x00\xff\xc4\x00\x14\x00\x01\x00\x00\x00\x00\x00\x00'
+    b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\t\xff\xc4\x00'
+    b'\x14\x10\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+    b'\x00\x00\x00\x00\x00\x00\xff\xda\x00\x08\x01\x01\x00'
+    b'\x00?\x00*\x9f\xff\xd9'
+)
+
+def test_stack_basic():
+    x = np.arange(12).reshape(3, 4)
+    io.push(x)
+
+    assert_array_equal(io.pop(), x)
+
+
+def test_stack_non_array():
+    with testing.raises(ValueError):
+        io.push([[1, 2, 3]])
+
+
+def test_imread_file_url():
+    # tweak data path so that file URI works on both unix and windows.
+    data_path = str(testing.fetch('data/camera.png'))
+    data_path = data_path.replace(os.path.sep, '/')
+    image_url = 'file:///{0}'.format(data_path)
+    image = io.imread(image_url)
+    assert image.shape == (512, 512)
+
+
+def test_imread_http_url(httpserver):
+    # httpserver is a fixture provided by pytest-localserver
+    # https://bitbucket.org/pytest-dev/pytest-localserver/
+    httpserver.serve_content(one_by_one_jpeg)
+    # it will serve anything you provide to it on its url.
+    # we add a /test.jpg so that we can identify the content
+    # by extension
+    image = io.imread(httpserver.url + '/test.jpg' + '?' + 's' * 266)
+    assert image.shape == (1, 1)
+
+
+def _named_tempfile_func(error_class):
+    """Create a mock function for NamedTemporaryFile that always raises.
+
+    Parameters
+    ----------
+    error_class : exception class
+        The error that should be raised when asking for a NamedTemporaryFile.
+
+    Returns
+    -------
+    named_temp_file : callable
+        A function that always raises the desired error.
+
+    Notes
+    -----
+    Although this function has general utility for raising errors, it is
+    expected to be used to raise errors that ``tempfile.NamedTemporaryFile``
+    from the Python standard library could raise. As of this writing, these
+    are ``FileNotFoundError``, ``FileExistsError``, ``PermissionError``, and
+    ``BaseException``. See
+    `this comment <https://github.com/scikit-image/scikit-image/issues/3785#issuecomment-486598307>`__
+    for more information.
+    """
+    def named_temp_file(*args, **kwargs):
+        raise error_class()
+    return named_temp_file
+
+
+@testing.parametrize(
+    'error_class', [
+        FileNotFoundError, FileExistsError, PermissionError, BaseException
+    ]
+)
+def test_failed_temporary_file(monkeypatch, error_class):
+    fetch('data/camera.png')
+    # tweak data path so that file URI works on both unix and windows.
+    data_path = data_dir.lstrip(os.path.sep)
+    data_path = data_path.replace(os.path.sep, '/')
+    image_url = 'file:///{0}/camera.png'.format(data_path)
+    with monkeypatch.context():
+        monkeypatch.setattr(
+            tempfile, 'NamedTemporaryFile', _named_tempfile_func(error_class)
+        )
+        with testing.raises(error_class):
+            image = io.imread(image_url)