Fixed database typo and removed unnecessary class identifier.

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

@@ -0,0 +1,135 @@
+
+import numpy as np
+from skimage import io
+from skimage._shared._warnings import expected_warnings
+import matplotlib.pyplot as plt
+
+
+def setup():
+    io.reset_plugins()
+
+# test images. Note that they don't have their full range for their dtype,
+# but we still expect the display range to equal the full dtype range.
+im8 = np.array([[0, 64], [128, 240]], np.uint8)
+im16 = im8.astype(np.uint16) * 256
+im64 = im8.astype(np.uint64)
+imf = im8 / 255
+im_lo = imf / 1000
+im_hi = imf + 10
+
+imshow_expected_warnings = [
+    r"tight_layout : falling back to Agg|\A\Z",
+    r"tight_layout: falling back to Agg|\A\Z",  # formatting change in mpl
+    # Maptlotlib 2.2.3 seems to use np.asscalar which issues a warning
+    # with numpy 1.16
+    # Matplotlib 2.2.3 is the last supported version for python 2.7
+    r"np.asscalar|\A\Z"
+]
+
+
+def n_subplots(ax_im):
+    """Return the number of subplots in the figure containing an ``AxesImage``.
+
+    Parameters
+    ----------
+    ax_im : matplotlib.pyplot.AxesImage object
+        The input ``AxesImage``.
+
+    Returns
+    -------
+    n : int
+        The number of subplots in the corresponding figure.
+
+    Notes
+    -----
+    This function is intended to check whether a colorbar was drawn, in
+    which case two subplots are expected. For standard imshows, one
+    subplot is expected.
+    """
+    return len(ax_im.get_figure().get_axes())
+
+
+def test_uint8():
+    plt.figure()
+    with expected_warnings(imshow_expected_warnings +
+                           [r"CObject type is marked|\A\Z"]):
+        ax_im = io.imshow(im8)
+    assert ax_im.cmap.name == 'gray'
+    assert ax_im.get_clim() == (0, 255)
+    assert n_subplots(ax_im) == 1
+    assert ax_im.colorbar is None
+
+
+def test_uint16():
+    plt.figure()
+    with expected_warnings(imshow_expected_warnings +
+                           [r"CObject type is marked|\A\Z"]):
+        ax_im = io.imshow(im16)
+    assert ax_im.cmap.name == 'gray'
+    assert ax_im.get_clim() == (0, 65535)
+    assert n_subplots(ax_im) == 1
+    assert ax_im.colorbar is None
+
+
+def test_float():
+    plt.figure()
+    with expected_warnings(imshow_expected_warnings +
+                           [r"CObject type is marked|\A\Z"]):
+        ax_im = io.imshow(imf)
+    assert ax_im.cmap.name == 'gray'
+    assert ax_im.get_clim() == (0, 1)
+    assert n_subplots(ax_im) == 1
+    assert ax_im.colorbar is None
+
+
+def test_low_data_range():
+    with expected_warnings(imshow_expected_warnings +
+                           ["Low image data range|CObject type is marked"]):
+        ax_im = io.imshow(im_lo)
+    assert ax_im.get_clim() == (im_lo.min(), im_lo.max())
+    # check that a colorbar was created
+    assert ax_im.colorbar is not None
+
+
+def test_outside_standard_range():
+    plt.figure()
+    # Warning raised by matplotlib on Windows:
+    # "The CObject type is marked Pending Deprecation in Python 2.7.
+    #  Please use capsule objects instead."
+    # Ref: https://docs.python.org/2/c-api/cobject.html
+    with expected_warnings(imshow_expected_warnings +
+                           ["out of standard range|CObject type is marked"]):
+        ax_im = io.imshow(im_hi)
+    assert ax_im.get_clim() == (im_hi.min(), im_hi.max())
+    assert n_subplots(ax_im) == 2
+    assert ax_im.colorbar is not None
+
+
+def test_nonstandard_type():
+    plt.figure()
+    # Warning raised by matplotlib on Windows:
+    # "The CObject type is marked Pending Deprecation in Python 2.7.
+    #  Please use capsule objects instead."
+    # Ref: https://docs.python.org/2/c-api/cobject.html
+    with expected_warnings(imshow_expected_warnings +
+                           ["Low image data range|CObject type is marked"]):
+        ax_im = io.imshow(im64)
+    assert ax_im.get_clim() == (im64.min(), im64.max())
+    assert n_subplots(ax_im) == 2
+    assert ax_im.colorbar is not None
+
+
+def test_signed_image():
+    plt.figure()
+    im_signed = np.array([[-0.5, -0.2], [0.1, 0.4]])
+
+    with expected_warnings(imshow_expected_warnings +
+                           [r"CObject type is marked|\A\Z"]):
+        ax_im = io.imshow(im_signed)
+    assert ax_im.get_clim() == (-0.5, 0.5)
+    assert n_subplots(ax_im) == 2
+    assert ax_im.colorbar is not None
+
+
+if __name__ == '__main__':
+    np.testing.run_module_suite()