BUG: pser.mode() should not be set series name

[Yikun]

Pandas version checks

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

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Reproducible Example

After 1.4.x:

import pandas as pd
pser = pd.Series([0, 0, 1, 1, 1])
pser.name = 'x'
pser.mode()

pser.mode()
0    1
Name: x, dtype: int64

Issue Description

pser.mode() should not be set series name.

Expected Behavior

Before 1.4:

pser.mode()
0    1
dtype: int64

Installed Versions

INSTALLED VERSIONS

commit : 4bfe3d0
python : 3.9.10.final.0
python-bits : 64
OS : Darwin
OS-release : 21.4.0
Version : Darwin Kernel Version 21.4.0: Mon Feb 21 20:35:58 PST 2022; root:xnu-8020.101.4~2/RELEASE_ARM64_T6000
machine : arm64
processor : arm
byteorder : little
LC_ALL : None
LANG : zh_CN.UTF-8
LOCALE : zh_CN.UTF-8

pandas : 1.4.2
numpy : 1.22.3
pytz : 2021.3
dateutil : 2.8.2
pip : 22.0.4
setuptools : 60.5.0
Cython : None
pytest : 7.1.0
hypothesis : None
sphinx : 3.0.4
blosc : None
feather : None
xlsxwriter : None
lxml.etree : None
html5lib : None
pymysql : None
psycopg2 : None
jinja2 : 2.11.3
IPython : 8.1.1
pandas_datareader: None
bs4 : 4.10.0
bottleneck : None
brotli : None
fastparquet : None
fsspec : None
gcsfs : None
markupsafe : 2.0.1
matplotlib : 3.2.2
numba : None
numexpr : None
odfpy : None
openpyxl : None
pandas_gbq : None
pyarrow : 7.0.0
pyreadstat : None
pyxlsb : None
s3fs : None
scipy : 1.8.0
snappy : None
sqlalchemy : 1.4.32
tables : None
tabulate : 0.8.9
xarray : None
xlrd : None
xlwt : None
zstandard : None

[Yikun]

first bad commit: 680e372

pandas/pandas/core/series.py

Lines 2061 to 2063 in cec066d

	return self._constructor(
	res_values, index=range(len(res_values)), name=self.name
	)

 return self._constructor( 
     res_values, index=range(len(res_values))
 ) 

[samukweku]

@Yikun Is this unique to mode or do other aggregations have the same output? E.g mean/median?

[Yikun]

@samukweku I think it's only in mode after 1.4.x，so I think it's an unexpected change.

[mroeschke]

Though it's an unexpected change, I think this is an accidental bug fix as Series.name should be preserved whenever possible. Doesn't appear to be a test for this so would be good to add one.

[henryh9n]

@Yikun @mroeschke I think the issue here is not that adding name=self.name fixed the bug, but that it was missing metadata propagation. I think it should be something like

        return self._constructor(
            res_values, index=range(len(res_values))
        ).__finalize__(
            self, method="mode"
        )

similar to all of the other methods. This will not only preserve the name, but also the other attributes (if there are, or will be, any others)