BUG: to_hdf fails with boolean index in 1.5

This issue has been tracked since 2022-09-20.

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Reproducible Example

import pandas as pd
pd.DataFrame([[False, 1]], columns=["a", "b"]).set_index(['a']).to_hdf("/tmp/a.hdf", "a")

Issue Description

When saving to_hdf a dataframe which has a boolean index I get an assertion error from inside pytables

   4943     return IndexCol(
   4944         name, values=converted, kind=kind, typ=atom, index_name=index_name
   4945     )
   4946 else:
-> 4947     assert isinstance(converted, np.ndarray) and converted.dtype == object
   4948     assert kind == "object", kind
   4949     atom = _tables().ObjectAtom()

AssertionError:

However, when saving a dataframe with no boolean in the index this works as expected.

Additionally saving dataframes with booleans in the index worked in 1.4.4

Expected Behavior

import pandas as pd
pd.DataFrame([[False, 1]], columns=["a", "b"]).set_index(['a']).to_hdf("/tmp/a.hdf", "a")

works identically to

import pandas as pd
pd.DataFrame([['False', 1]], columns=["a", "b"]).set_index(['a']).to_hdf("/tmp/a.hdf", "a")

Installed Versions

INSTALLED VERSIONS

commit : 87cfe4e
python : 3.10.7.final.0
python-bits : 64
OS : Linux
OS-release : 5.4.117.hrtdev
Version : #3 SMP Tue May 11 13:44:03 EDT 2021
machine : x86_64
processor :
byteorder : little
LC_ALL :
LANG : en_US.UTF-8
LOCALE : en_US.UTF-8

pandas : 1.5.0
numpy : 1.23.2
pytz : 2022.1
dateutil : 2.8.2
setuptools : 62.1.0
pip : 22.2.2
Cython : 0.29.30
pytest : 7.1.2
hypothesis : 6.52.3
sphinx : 5.0.2
blosc : 1.10.6
feather : None
xlsxwriter : None
lxml.etree : 4.9.1
html5lib : 1.1
pymysql : 1.0.2
psycopg2 : 2.9.3
jinja2 : 3.1.2
IPython : 8.4.0
pandas_datareader: None
bs4 : 4.11.1
bottleneck : 1.3.5
brotli : 1.0.9
fastparquet : 0.8.1
fsspec : 2022.5.0
gcsfs : None
matplotlib : 3.5.2
numba : 0.56.2
numexpr : 2.8.3
odfpy : None
openpyxl : 3.0.10
pandas_gbq : None
pyarrow : 7.0.0
pyreadstat : None
pyxlsb : 1.0.9
s3fs : None
scipy : 1.9.1
snappy : None
sqlalchemy : 1.4.39
tables : 3.7.0
tabulate : 0.8.10
xarray : 2022.6.0
xlrd : 2.0.1
xlwt : None
zstandard : 0.18.0
tzdata : 2022.1

anthonyaag wrote this answer on 2022-09-21

Seems to be a change from the dtype of the index

1.5 behavior
In [12]: pd.DataFrame([[True, 1]], columns=["a", "b"]).set_index("a").index
Out[12]: Index([True], dtype='bool', name='a')

1.4 behavior
In [11]: pd.DataFrame([[True, 1]], columns=["a", "b"]).set_index("a").index
Out[11]: Index([True], dtype='object', name='a')

phofl wrote this answer on 2022-09-21
ee6b0a09fff7789879c3322edffe9f84d10acee3 is the first bad commit
commit ee6b0a09fff7789879c3322edffe9f84d10acee3
Author: jbrockmendel <[email protected]>
Date:   Sat Feb 5 11:01:21 2022 -0800

    ENH: Index[bool] (#45061)
More Details About Repo
Owner Name pandas-dev
Repo Name pandas
Full Name pandas-dev/pandas
Language Python
Created Date 2010-08-24
Updated Date 2022-10-04
Star Count 35430
Watcher Count 1120
Fork Count 15089
Issue Count 3589

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