from __future__ import division

import numpy as np
from skimage import io

io.use_plugin('matplotlib', 'imshow')


# 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
imf = im8 / 255
im_lo = imf / 1000
im_hi = imf + 10



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():
    ax_im = io.imshow(im8)
    assert ax_im.cmap.name == 'gray'
    assert ax_im.get_clim() == (0, 255)
    assert n_subplots(ax_im) == 1


def test_uint16():
    ax_im = io.imshow(im16)
    assert ax_im.cmap.name == 'gray'
    assert ax_im.get_clim() == (0, 65535)
    assert n_subplots(ax_im) == 1


def test_float():
    ax_im = io.imshow(imf)
    assert ax_im.cmap.name == 'gray'
    assert ax_im.get_clim() == (0, 1)
    assert n_subplots(ax_im) == 1


if __name__ == '__main__':
    np.testing.run_module_suite()

Add tests for io.imshow mpl plugin
Add tests for io.imshow mpl plugin
