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BUG: Unnecessary NonExistentTimeError when resampling weekly #53666

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@MarcoGorelli

Description

@MarcoGorelli

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

df = pd.DataFrame({
    'ts': [datetime(2005, 10, 9, 21)],
    'values': [10.]
})
df['ts'] = df['ts'].dt.tz_localize('Chile/Continental')
df.resample('W-Mon', on='ts', closed='left', label='left')

Issue Description

This throws

NonExistentTimeError: 2005-10-09 00:00:00

I don't see why it should need to though - the window it needs to create is [2005-10-03, 2005-10-10), so why would it matter that there's a non-existent time in that interval?

Expected Behavior

                         ts  values
0 2005-10-03 00:00:00-04:00    10.0

For reference, polars would give that output:

In [35]: (
    ...:     pl.from_pandas(df)
    ...:     .with_columns(pl.col("ts").set_sorted())
    ...:     .groupby_dynamic("ts", every="1w", start_by="monday")
    ...:     .agg(pl.col("values").sum())
    ...: )
Out[35]:
shape: (1, 2)
┌─────────────────────────────────┬────────┐
│ tsvalues │
│ ------    │
│ datetime[ns, Chile/Continental] ┆ f64    │
╞═════════════════════════════════╪════════╡
│ 2005-10-03 00:00:00 -0410.0   │
└─────────────────────────────────┴────────┘

Installed Versions

INSTALLED VERSIONS

commit : 965ceca
python : 3.10.6.final.0
python-bits : 64
OS : Linux
OS-release : 5.10.102.1-microsoft-standard-WSL2
Version : #1 SMP Wed Mar 2 00:30:59 UTC 2022
machine : x86_64
processor : x86_64
byteorder : little
LC_ALL : None
LANG : en_GB.UTF-8
LOCALE : en_GB.UTF-8

pandas : 2.0.2
numpy : 1.24.3
pytz : 2023.3
dateutil : 2.8.2
setuptools : 67.6.1
pip : 23.0.1
Cython : None
pytest : 7.3.1
hypothesis : None
sphinx : None
blosc : None
feather : None
xlsxwriter : None
lxml.etree : None
html5lib : None
pymysql : None
psycopg2 : None
jinja2 : 3.1.2
IPython : 8.13.2
pandas_datareader: None
bs4 : 4.12.2
bottleneck : None
brotli : None
fastparquet : None
fsspec : None
gcsfs : None
matplotlib : 3.7.1
numba : None
numexpr : None
odfpy : None
openpyxl : None
pandas_gbq : None
pyarrow : 12.0.0
pyreadstat : None
pyxlsb : None
s3fs : None
scipy : None
snappy : None
sqlalchemy : None
tables : None
tabulate : None
xarray : None
xlrd : None
zstandard : None
tzdata : 2023.3
qtpy : None
pyqt5 : None

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