BUG: `test_arange()` fails on Dask due to illegal dtype

[crusaderky]

test_arange has started failing on dask:
https://github.com/data-apis/array-api-compat/actions/runs/13034089416/job/36360099375?pr=244

exc = NotImplementedError('An error occurred while calling the arange method registered to the numpy backend.\nOriginal Message: Can not use auto rechunking with object dtype. We are unable to estimate the size in bytes of object data')

This is unrelated to the recent changes to dask in array-api-compat.
The problem is that the test calls da.arange(..., dtype=object), which is not a valid dtype according to the Array API standard.

[ev-br]

FWIW, I find it hard to believe it's unrelated to recent dask related changes. The test, while quite hairy,

• has no reason to generate dtype=object
• was not generating dtype=object until recently
• today, does not generate dtype=object on anything other than dask.

[crusaderky]

Not a regression in array-api-compat, nor array-api-tests, nor dask.
I could not find out what started it.

>>> start, stop, step = 0., -9_131_138_316_486_228_481, -92_233_720_368_547_759
>>> da.arange(start, stop, step)

NotImplementedError: An error occurred while calling the arange method registered to the numpy backend.
Original Message: Can not use auto rechunking with object dtype. We are unable to estimate the size in bytes of object data

dask does not support float parameters.

dask internally multiplies step * 100 to divine the dtype, which in turn sends step beyond the limit of int64, which in turn triggers edge case behaviour on behalf of numpy:

>>> np.arange(start, stop, step * 100)
array([0.0], dtype=object)

[ev-br]

Ouch. So the right fix is to limit the range for step that moster of a hypothesis test, apparently.

[ev-br]

A first shot could be to add one more assume, like assume(abs(step) < M // 2) to
https://github.com/data-apis/array-api-tests/blob/master/array_api_tests/test_creation_functions.py#L133
?

Generally adding assumes makes it more likely to get hypothesis health check warnings, but maybe we'll be lucky here.

[crusaderky]

The input is legal though. This is a bug in dask.
The last person to touch it was... myself, seven years ago: dask/dask#3722

[crusaderky]

dask/dask#11707 fixes it upstream