uproot 5.6.8 fails to write simplest pandas DataFrames as root files #1523
Description
Dear uproot developers, uproot seems to have suddenly lost its ability to save pandas data frames as root files. Previous versions of uproot5 can do this.
>>> import uproot
>>> uproot.__version__uproot 5.6.8
Example
import uproot
import pandas
df = pandas.DataFrame({"a" : [1,2,3], "b" : [4,5,6]})
with uproot.recreate("file.root") as f:
f["mytree"] = dfError:
Traceback (most recent call last):
File "/projectpath/debug/test.py", line 9, in <module>
f["mytree"] = df
~^^^^^^^^^^
File "/envpath/envs/py/lib/python3.13/site-packages/uproot/writing/writable.py", line 986, in __setitem__
self.update({where: what})
~~~~~~~~~~~^^^^^^^^^^^^^^^
File "/envpath/envs/py/lib/python3.13/site-packages/uproot/writing/writable.py", line 1598, in update
uproot.writing.identify.add_to_directory(v, name, directory, streamers)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/envpath/envs/py/lib/python3.13/site-packages/uproot/writing/identify.py", line 57, in add_to_directory
obj = uproot.writing.writable._regularize_input_type(obj)
File "/envpath/envs/py/lib/python3.13/site-packages/uproot/writing/writable.py", line 2227, in _regularize_input_type
obj = uproot.writing._cascadetree.dataframe_to_dict(obj)
^^^^^^^^^^^^^^^^^^^^^^^^^^^
AttributeError: module 'uproot.writing' has no attribute '_cascadetree'