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BUG: loc setitem fails with shape mismatch #51450

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@sam-infinity

Description

@sam-infinity

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Reproducible Example

import pandas as pd

df = pd.DataFrame({
    "A": [],
    "B": []
}).astype('str')

df.loc[df['A'].str.contains('STUFF'), ['A']] = df['A'] + '-' + df['B']

Issue Description

In versions 1.5+ this errors with ValueError: shape mismatch: value array of shape (0,) could not be broadcast to indexing result of shape (0,1)

Expected Behavior

In pre 1.5 this behaved as a no-op.

Installed Versions

INSTALLED VERSIONS

commit : 2e218d1
python : 3.9.7.final.0
python-bits : 64
OS : Darwin
OS-release : 21.6.0
Version : Darwin Kernel Version 21.6.0: Mon Dec 19 20:44:01 PST 2022; root:xnu-8020.240.18~2/RELEASE_X86_64
machine : x86_64
processor : i386
byteorder : little
LC_ALL : None
LANG : en_US.UTF-8
LOCALE : en_US.UTF-8

pandas : 1.5.3
numpy : 1.24.2
pytz : 2022.7.1
dateutil : 2.8.2
setuptools : 57.4.0
pip : 21.2.3
Cython : None
pytest : None
hypothesis : None
sphinx : None
blosc : None
feather : None
xlsxwriter : None
lxml.etree : None
html5lib : None
pymysql : None
psycopg2 : None
jinja2 : None
IPython : None
pandas_datareader: None
bs4 : None
bottleneck : None
brotli : None
fastparquet : None
fsspec : None
gcsfs : None
matplotlib : None
numba : None
numexpr : None
odfpy : None
openpyxl : None
pandas_gbq : None
pyarrow : None
pyreadstat : None
pyxlsb : None
s3fs : None
scipy : None
snappy : None
sqlalchemy : None
tables : None
tabulate : None
xarray : None
xlrd : None
xlwt : None
zstandard : None
tzdata : None

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    BugIndexingRelated to indexing on series/frames, not to indexes themselvesRegressionFunctionality that used to work in a prior pandas version

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