BUG: to_hdf fails with boolean index in 1.5

[anthonyaag]

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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 : 87cfe4e38bafe7300a6003a1d18bd80f3f77c763 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]

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]

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)