I intend to upload pandas 2.3.1 (in Salsa) to experimental today.

Upstream release notes:
https://pandas.pydata.org/docs/whatsnew/v2.3.0.html

Nothing obviously compatibility-breaking, but the new deprecations might
fail fail-on-warning test suites.

To test:
abinit asammdf astropy augur azure-kusto-python beangrow bmtk boinor
bqplot busco camelot-py cfgrib changeo cnvkit dask dask.distributed
datalab debian-astro debian-pan debian-science dials dioptas dipy
domdf-python-tools drms dxchange dyda edlio emperor esda
exchange-calendars extra-data flox folium glueviz guidata harmonypy hdmf
hickle influxdb-python intake ipython jitterdebugger joblib joypy
json-tricks jsonpickle jupyter-cache libpysal lmfit-py loki-ecmwf
macsyfinder mapclassify mcaller mdtraj metaphlan metpy metview-python
mirtop mkdocs-test mlpack monty myst-nb nanofilt napari nbsphinx
networkx nipype openpyxl orange3 osmnx pairtools parmed partd patsy
pdb2pqr pg-statviz pint-xarray plasmidid pointpats poretools presto
psychopy pybel pychopper pycoqc pydevd pyensembl pyinstaller pymatgen
pymecavideo pynwb pyodc pyranges pyreadstat pyrle pytest-regressions
python-aioinflux python-airr python-altair python-anndata
python-apptools python-azure python-bioframe python-biom-format
python-bioregistry python-calendra python-cgelib python-clevercsv
python-cobra python-cogent python-cooler python-curies python-datacache
python-django-pint python-dynasor python-fastparquet
python-feather-format python-fluids python-geopandas python-geotiepoints
python-gsd python-gtfparse python-hypothesis python-igraph
python-influxdb-client python-iow python-loompy python-lsp-server
python-maggma python-momepy python-nanoget python-nanomath python-ncls
python-numpy-groupies python-pandas-flavor python-parsl python-pauvre
python-peakutils python-petl python-pomegranate python-pyani
python-pybedtools python-pyfakefs python-pymeasure python-pyomop
python-pyproj python-rdata python-skbio python-streamz python-tablib
python-tabulate python-testbook python-throttler python-treetime
python-ulmo python-upsetplot python-vega-datasets python-xarray
python-xrt pytorch-geometric pytroll-schedule pyxnat q2-cutadapt
q2-demux q2-diversity-lib q2-emperor q2-metadata q2-quality-control
q2-quality-filter q2-taxa q2-types q2templates qiime r-bioc-mofa
rapidfuzz rdkit recan refnx rickslab-gpu-utils sarsen scikit-learn
scikit-optimize scikit-rf seaborn sentineldl sherlock skimage
sklearn-pandas skorch skyfield slm snakemake sorted-nearest spaghetti
sphinx-book-theme spopt spyder spyder-kernels statsmodels stimfit sunpy
topplot tqdm traittypes umap-learn umis xarray-safe-s1 xarray-sentinel
xgboost xpore xraylarch yanagiba

No build failures on release architectures, but riscv64 hasn't tried yet.

No autopkgtest failures that look pandas-related.  (jupyter-cache
(#1113702) looks like a random failure; openpyxl (#1112366), spyder
(#1112173) and dask/dask.distributed/pyomop/xarray (llhttp
uninstallability) were already broken.)

dask, xarray, etc have now passed their autopkgtests.

Since this looked like a problem-free transition, I ran the build test
only for packages that didn't have a (non-superficial) autopkgtest.  It
found two issues:

- pandas.__version__ includes the +dfsg suffix.  Such versions are
allowed by the Python packaging spec (
https://packaging.python.org/en/latest/specifications/version-specifiers/#local-version-identifiers
), but mlpack's build considers them invalid.
https://launchpadlibrarian.net/815552441/buildlog_ubuntu-questing-amd64.mlpack_4.6.0-1_BUILDING.txt.gz

This was probably triggered by starting to use pyproject / mesonpy, but
it's unclear how general a problem it is.  Of the other mesonpy
packages, matplotlib also has it in meson's "Project version" (I haven't
checked the final package) but numpy and scikit-misc don't.

- tqdm's tests fail on warnings, and trigger one of the new warnings.
https://launchpadlibrarian.net/815545434/buildlog_ubuntu-questing-amd64.tqdm_4.67.1-5_BUILDING.txt.gz

Note that pandas 2.2, but not 2.3, currently FTBFS (due to pytest 8.4,
#1114251), and I would hence like to get this transition finished soon.

Fixed in Salsa, but not yet uploaded because of the tqdm issue below.

(Should this be versioned 2.3.2+dfsg-1 or 2.3.2+dfsg-2?  I uploaded a
2.3.2+dfsg-1 without this fix to my build-testing PPA
https://launchpad.net/~rebecca-palmer/+archive/ubuntu/pandas2p3 , but
not to the Debian archive.)
Reported as #1114885, with patch included.  Awaiting maintainer response.

pandas 2.3 has now been uploaded to unstable, closing these bugs.