Failure on `main` testing xarray.cross

[TomNicholas]

What happened?

Failure on main testing xarray.cross

https://github.com/pydata/xarray/actions/runs/10298827771/job/28504816043#step:10:838

Possibly either a bug in apply_ufunc or an incorrect use of it.

What did you expect to happen?

No response

Minimal Complete Verifiable Example

No response

MVCE confirmation

• [ ] Minimal example — the example is as focused as reasonably possible to demonstrate the underlying issue in xarray.
• [ ] Complete example — the example is self-contained, including all data and the text of any traceback.
• [ ] Verifiable example — the example copy & pastes into an IPython prompt or Binder notebook, returning the result.
• [X] New issue — a search of GitHub Issues suggests this is not a duplicate.
• [ ] Recent environment — the issue occurs with the latest version of xarray and its dependencies.

Relevant log output

No response

Anything else we need to know?

No response

Environment

main

[kmuehlbauer]

It looks like this surfaced with new numpy 2.0.1 release in connection with dask 2024.8.0.

• breaks with dask 2024.8.0 and numpy 2.0.1
• works with dask 2024.8.0 and numpy 2.0.0
• works with dask 2024.7.1 and numpy 2.0.1

[kmuehlbauer]

So from what I can tell the align-path in below code should align a and b. But it returns multiple chunks instead of one chunk.

In the following elif-path there is special handling to rechunk. Hope this helps to figure out a solution.

https://github.com/pydata/xarray/blob/b22c4296f70ea9bf59cc1c8e6c34346489046338/xarray/core/computation.py#L1669-L1705