issues

What happened?

The doctest CI job for my Pull Request failed. The failure seems at first glance to be unrelated to my code changes. It seems related to a Dask warning.

Note: I create this issue for logging purposes ; it might become relevant only once another unrelated PR is subject to the same bug.

What did you expect to happen?

I expected the doctest CI Job to pass. This error happens both on the online CI and locally when running

python -m pytest --doctest-modules xarray --ignore xarray/tests --ignore xarray/datatree_ -Werror

(the command is taken from the CI definition file: https://github.com/pydata/xarray/actions/runs/7854959732/workflow?pr=8698#L83)

Minimal Complete Verifiable Example

Python N/A

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.
• [ ] 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

```Python =================================== FAILURES =================================== _ [doctest] xarray.core.dataarray.DataArray.to_dask_dataframe __________ 7373 ... dims=("time", "lat", "lon"), 7374 ... coords={ 7375 ... "time": np.arange(4), 7376 ... "lat": [-30, -20], 7377 ... "lon": [120, 130], 7378 ... }, 7379 ... name="eg_dataarray", 7380 ... attrs={"units": "Celsius", "description": "Random temperature data"}, 7381 ... ) 7382 >>> da.to_dask_dataframe(["lat", "lon", "time"]).compute() UNEXPECTED EXCEPTION: DeprecationWarning("The current Dask DataFrame implementation is deprecated. \nIn a future release, Dask DataFrame will use new implementation that\ncontains several improvements including a logical query planning.\nThe user-facing DataFrame API will remain unchanged.\n\nThe new implementation is already available and can be enabled by\ninstalling the dask-expr library:\n\n $ pip install dask-expr\n\nand turning the query planning option on:\n\n >>> import dask\n >>> dask.config.set({'dataframe.query-planning': True})\n >>> import dask.dataframe as dd\n\nAPI documentation for the new implementation is available at\nhttps://docs.dask.org/en/stable/dask-expr-api.html\n\nAny feedback can be reported on the Dask issue tracker\nhttps://github.com/dask/dask/issues \n") Traceback (most recent call last): File "/home/runner/micromamba/envs/xarray-tests/lib/python3.11/doctest.py", line 1353, in __run exec(compile(example.source, filename, "single", File "<doctest xarray.core.dataarray.DataArray.to_dask_dataframe[1]>", line 1, in <module> File "/home/runner/work/xarray/xarray/xarray/core/dataarray.py", line 7408, in to_dask_dataframe return ds.to_dask_dataframe(dim_order, set_index) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/home/runner/work/xarray/xarray/xarray/core/dataset.py", line 7369, in to_dask_dataframe import dask.dataframe as dd File "/home/runner/micromamba/envs/xarray-tests/lib/python3.11/site-packages/dask/dataframe/__init.py", line 162, in <module> warnings.warn( DeprecationWarning: The current Dask DataFrame implementation is deprecated. In a future release, Dask DataFrame will use new implementation that contains several improvements including a logical query planning. The user-facing DataFrame API will remain unchanged.

The new implementation is already available and can be enabled by installing the dask-expr library:

$ pip install dask-expr

and turning the query planning option on:

>>> import dask
>>> dask.config.set({'dataframe.query-planning': True})
>>> import dask.dataframe as dd

API documentation for the new implementation is available at https://docs.dask.org/en/stable/dask-expr-api.html

Any feedback can be reported on the Dask issue tracker https://github.com/dask/dask/issues /home/runner/work/xarray/xarray/xarray/core/dataarray.py:7382: UnexpectedException =========================== short test summary info ============================ FAILED xarray/core/dataarray.py::xarray.core.dataarray.DataArray.to_dask_dataframe ============= 1 failed, 301 passed, 2 skipped in 78.04s (0:01:18) ============== Error: Process completed with exit code 1. ```

Anything else we need to know?

No response

Environment

N/A