numpy.array_equal() returns False on apparently identical arrays with NaN values

OS: macOS Sierra (10.12.5) Python version: 2.7.12 numpy version: 1.13.0

Passing np.array_equal() two apparently identical arrays containing NaN values returns False. See the following example replicating this issue:

>>> a = np.array([1, 2, np.nan])
>>> np.array_equal(a, a)
False

It would make sense to me if this returned True, though I understand that the following comparison returns False by definition:

>>> np.nan == np.nan
False

I presume this is related to changes in np.equal and np.not_equal. If this is the desired behaviour, I wonder if it might be more helpful for the element-wise comparison to raise an exception on encountering NaN comparisons, as this has caused unit test failures for me and took a while to track down.

[charris]

Might be good to add an equal_nan argument.

In [3]: np.allclose(a, a, equal_nan=True)
Out[3]: True

[rossbar]

As @charris commented, it might be good to add an equal_nan argument, just as in allclose.

A particular reason why no one followed up on this suggestion?

The equal_nan kwarg has been added in #16128, which should be sufficient to close the issue. If there is still discussion to be had about np.testing.assert_array_equal, feel free to re-open or, better yet, open a new issue that links to the relevant comments here.