BUG: DataFrame.rename() does not replace existing columns

[xl0]

Pandas version checks

• I have checked that this issue has not already been reported.

• I have confirmed this bug exists on the latest version of pandas.

• I have confirmed this bug exists on the main branch of pandas.

Reproducible Example

import pandas as pd
df = pd.DataFrame(index=[1, 2, 3], columns=["a"], data=[1, 2, 3])

df.rename(columns={"a" : "A"}, inplace=True)
df["a"] = [1, 2, 3]

df.rename(columns={"a" : "A"}, inplace=True)
print(df)

Issue Description

   A  A
1  1  1
2  2  2
3  3  3

DataFrame.rename() does not check if a column already exists.

Expected Behavior

DataFrame.rename() should replace the existing column:

   A
1  1
2  2
3  3

I would expect df.rename() to be equivalent to

df["A"] = df["a"],
df.drop(columns=["a"], inplace=True)

Installed Versions

INSTALLED VERSIONS

commit : 4bfe3d0
python : 3.9.10.final.0
python-bits : 64
OS : Linux
OS-release : 5.4.0-107-generic
Version : #121-Ubuntu SMP Thu Mar 24 16:04:27 UTC 2022
machine : x86_64
processor : x86_64
byteorder : little
LC_ALL : None
LANG : en_US.UTF-8
LOCALE : en_US.UTF-8

pandas : 1.4.2
numpy : 1.21.2
pytz : 2021.3
dateutil : 2.8.2
pip : 21.2.4
setuptools : 58.0.4
Cython : None
pytest : None
hypothesis : None
sphinx : 4.4.0
blosc : None
feather : None
xlsxwriter : None
lxml.etree : None
html5lib : None
pymysql : None
psycopg2 : None
jinja2 : 3.0.2
IPython : 7.31.1
pandas_datareader: None
bs4 : 4.10.0
bottleneck : 1.3.2
brotli :
fastparquet : None
fsspec : None
gcsfs : None
markupsafe : 2.0.1
matplotlib : 3.5.0
numba : None
numexpr : 2.8.1
odfpy : None
openpyxl : None
pandas_gbq : None
pyarrow : None
pyreadstat : None
pyxlsb : None
s3fs : None
scipy : 1.7.3
snappy : None
sqlalchemy : None
tables : None
tabulate : None
xarray : None
xlrd : None
xlwt : None
zstandard : None

[phofl]

Hi, thanks for your report. This is the intended behavior. Please see #45486 for example