'Test files that have some identical HDUs but one different HDU.'

def test_partially_identical_files2(self):

    a = np.arange(100).reshape((10, 10))
    phdu = PrimaryHDU(data=a)
    ehdu = ImageHDU(data=a)
    ehdu2 = ImageHDU(data=(a + 1))
    hdula = HDUList([phdu, ehdu, ehdu])
    hdulb = HDUList([phdu, ehdu2, ehdu])
    diff = FITSDiff(hdula, hdulb)
    assert (not diff.identical)
    assert (diff.diff_hdu_count == ())
    assert (len(diff.diff_hdus) == 1)
    assert (diff.diff_hdus[0][0] == 1)
    hdudiff = diff.diff_hdus[0][1]
    assert (not hdudiff.identical)
    assert (hdudiff.diff_extnames == ())
    assert (hdudiff.diff_extvers == ())
    assert (hdudiff.diff_extension_types == ())
    assert hdudiff.diff_headers.identical
    assert (hdudiff.diff_data is not None)
    datadiff = hdudiff.diff_data
    assert isinstance(datadiff, ImageDataDiff)
    assert (not datadiff.identical)
    assert (datadiff.diff_dimensions == ())
    assert (datadiff.diff_pixels == [((0, y), (y, (y + 1))) for y in range(10)])
    assert (datadiff.diff_ratio == 1.0)
    assert (datadiff.diff_total == 100)
    report = diff.report()
    assert ('Primary    HDU' not in report)
    assert ('Extension    HDU    2' not in report)
    assert ('Extension    HDU    1' in report)
    assert ('Headers    contain    differences' not in report)
    assert ('Data    contains    differences' in report)
    for y in range(10):
        assert ('Data    differs    at    [{},    1]'.format((y + 1)) in report)
    assert ('100    different    pixels    found    (100.00%    different).' in report)
