groupby on multi-index level is grouping by the multi-index (reappearance of #6836)

[carynbear]

What happened?

This is the same issue as #6836

Given a multiindex "x" --> ("one", "two")
Groupby on a multi-index level ("one") is grouping by the multi-index ("x") instead of level.

midx = pd.MultiIndex.from_product([list("abc"), [0, 1]], names=("one", "two"))
mda = xr.DataArray(np.random.rand(6, 3), [("x", midx), ("y", range(3))])
mda.groupby("one").groups

{('a', 0): [0],
 ('a', 1): [1],
 ('b', 0): [2],
 ('b', 1): [3],
 ('c', 0): [4],
 ('c', 1): [5]}

What did you expect to happen?

Should return

{'a': [0, 1],
 'b': [2, 3],
 'c': [4, 5]}

Minimal Complete Verifiable Example

midx = pd.MultiIndex.from_product([list("abc"), [0, 1]], names=("one", "two"))
mda = xr.DataArray(np.random.rand(6, 3), [("x", midx), ("y", range(3))])
mda.groupby("one").groups

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

No response

Anything else we need to know?

No response

Environment

INSTALLED VERSIONS

commit: None
python: 3.9.2 (default, Feb 28 2021, 17:03:44)
[GCC 10.2.1 20210110]
python-bits: 64
OS: Linux
OS-release: 5.10.0-30-cloud-amd64
machine: x86_64
processor:
byteorder: little
LC_ALL: None
LANG: C.UTF-8
LOCALE: ('en_US', 'UTF-8')
libhdf5: None
libnetcdf: None

xarray: 2023.1.0
pandas: 2.0.3
numpy: 1.24.4
scipy: 1.9.3
netCDF4: None
pydap: None
h5netcdf: None
h5py: None
Nio: None
zarr: None
cftime: None
nc_time_axis: None
PseudoNetCDF: None
rasterio: None
cfgrib: None
iris: None
bottleneck: None
dask: None
distributed: None
matplotlib: 3.7.5
cartopy: None
seaborn: None
numbagg: None
fsspec: None
cupy: None
pint: None
sparse: None
flox: None
numpy_groupies: None
setuptools: None
pip: None
conda: None
pytest: None
mypy: None
IPython: 8.12.3
sphinx: None

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[dcherian]

xarray: 2023.1.0

please update xarray

[carynbear]

Okay it works with 2024.7.0. Thanks