Or you could write `assertMaskedArrayEqual` :wink:. Just pop it in `IrisTest` (in lib/iris/tests/__init__.py) in between `assertArrayAlmostEqual` and `assertMaskedArrayAlmostEqual`. Its form will be basically the same as `assertMaskedArrayAlmostEqual` except with the `assert_array_almost_equal` changed to `assert_array_equal`. This would be a valuable addition.