Xarray: upstream-dev CI fails on import of dask.array

[keewis]

I'm not sure why, but our upstream-dev CI fails when importing dask.array: https://dev.azure.com/xarray/xarray/_build/results?buildId=2996&view=logs&j=2280efed-fda1-53bd-9213-1fa8ec9b4fa8&t=aa9ddc6e-3e6c-56cb-4312-111c01d6f735

[keewis]

It seems that's because we use python -OO -c "import xarray" to test importing, and the optimization (no asserts / __debug__ related stuff) makes import dask.array fail.

[dcherian]

This has propagated to all tests: https://dev.azure.com/xarray/xarray/_build/results?buildId=3005&view=results

[jsignell]

Working on a fix now. I think https://github.com/dask/dask/pull/6299 should do it.

[dcherian]

Awesome. Thanks @jsignell

[keewis]

the fix by @jsignell is now on dask master so the upstream-dev CI should work, but our other CI will keep failing until dask=2.18.1 or dask=2.19.0 is released.

In the meantime, we could pin dask to dask!=2.18.0 or remove the -OO option in the CI. Does anyone know why we use that option?

[dcherian]

or remove the -OO option in the CI. Does anyone know why we use that option?

Looks like @shoyer added that line initially. Lets try removing it?

[jsignell]

I think dask is going to release today.

[shoyer]

I would suggest pinning dask for now (or waiting until the new release).

[keewis]

dask==2.18.1 has been released so I'm closing this