BUG: incorrect type hint for subset in dropna

[stevenlis]

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
data = {'col1': [1, 3, 4], 'col2': [2, 3, 5], 'col2': [2, 4, 4]}
df = pd.DataFrame(data)

df.dropna(subset=df.columns.drop('col1'))

Issue Description

pandas/pandas/core/frame.py

Lines 6413 to 6573 in 91111fd

	@deprecate_nonkeyword_arguments(version=None, allowed_args=["self"])
	def dropna(
	self,
	axis: Axis = 0,
	how: str | NoDefault = no_default,
	thresh: int | NoDefault = no_default,
	subset: IndexLabel = None,
	inplace: bool = False,
	) -> DataFrame | None:
	"""
	Remove missing values.
	See the :ref:`User Guide <missing_data>` for more on which values are
	considered missing, and how to work with missing data.
	Parameters
	----------
	axis : {0 or 'index', 1 or 'columns'}, default 0
	Determine if rows or columns which contain missing values are
	removed.
	* 0, or 'index' : Drop rows which contain missing values.
	* 1, or 'columns' : Drop columns which contain missing value.
	.. versionchanged:: 1.0.0
	Pass tuple or list to drop on multiple axes.
	Only a single axis is allowed.
	how : {'any', 'all'}, default 'any'
	Determine if row or column is removed from DataFrame, when we have
	at least one NA or all NA.
	* 'any' : If any NA values are present, drop that row or column.
	* 'all' : If all values are NA, drop that row or column.
	thresh : int, optional
	Require that many non-NA values. Cannot be combined with how.
	subset : column label or sequence of labels, optional
	Labels along other axis to consider, e.g. if you are dropping rows
	these would be a list of columns to include.
	inplace : bool, default False
	Whether to modify the DataFrame rather than creating a new one.
	Returns
	-------
	DataFrame or None
	DataFrame with NA entries dropped from it or None if ``inplace=True``.
	See Also
	--------
	DataFrame.isna: Indicate missing values.
	DataFrame.notna : Indicate existing (non-missing) values.
	DataFrame.fillna : Replace missing values.
	Series.dropna : Drop missing values.
	Index.dropna : Drop missing indices.
	Examples
	--------
	>>> df = pd.DataFrame({"name": ['Alfred', 'Batman', 'Catwoman'],
	... "toy": [np.nan, 'Batmobile', 'Bullwhip'],
	... "born": [pd.NaT, pd.Timestamp("1940-04-25"),
	... pd.NaT]})
	>>> df
	name toy born
	0 Alfred NaN NaT
	1 Batman Batmobile 1940-04-25
	2 Catwoman Bullwhip NaT
	Drop the rows where at least one element is missing.
	>>> df.dropna()
	name toy born
	1 Batman Batmobile 1940-04-25
	Drop the columns where at least one element is missing.
	>>> df.dropna(axis='columns')
	name
	0 Alfred
	1 Batman
	2 Catwoman
	Drop the rows where all elements are missing.
	>>> df.dropna(how='all')
	name toy born
	0 Alfred NaN NaT
	1 Batman Batmobile 1940-04-25
	2 Catwoman Bullwhip NaT
	Keep only the rows with at least 2 non-NA values.
	>>> df.dropna(thresh=2)
	name toy born
	1 Batman Batmobile 1940-04-25
	2 Catwoman Bullwhip NaT
	Define in which columns to look for missing values.
	>>> df.dropna(subset=['name', 'toy'])
	name toy born
	1 Batman Batmobile 1940-04-25
	2 Catwoman Bullwhip NaT
	Keep the DataFrame with valid entries in the same variable.
	>>> df.dropna(inplace=True)
	>>> df
	name toy born
	1 Batman Batmobile 1940-04-25
	"""
	if (how is not no_default) and (thresh is not no_default):
	raise TypeError(
	"You cannot set both the how and thresh arguments at the same time."
	)
	if how is no_default:
	how = "any"
	inplace = validate_bool_kwarg(inplace, "inplace")
	if isinstance(axis, (tuple, list)):
	# GH20987
	raise TypeError("supplying multiple axes to axis is no longer supported.")
	axis = self._get_axis_number(axis)
	agg_axis = 1 - axis
	agg_obj = self
	if subset is not None:
	# subset needs to be list
	if not is_list_like(subset):
	subset = [subset]
	ax = self._get_axis(agg_axis)
	indices = ax.get_indexer_for(subset)
	check = indices == -1
	if check.any():
	raise KeyError(np.array(subset)[check].tolist())
	agg_obj = self.take(indices, axis=agg_axis)
	if thresh is not no_default:
	count = agg_obj.count(axis=agg_axis)
	mask = count >= thresh
	elif how == "any":
	# faster equivalent to 'agg_obj.count(agg_axis) == self.shape[agg_axis]'
	mask = notna(agg_obj).all(axis=agg_axis, bool_only=False)
	elif how == "all":
	# faster equivalent to 'agg_obj.count(agg_axis) > 0'
	mask = notna(agg_obj).any(axis=agg_axis, bool_only=False)
	else:
	raise ValueError(f"invalid how option: {how}")
	if np.all(mask):
	result = self.copy()
	else:
	result = self.loc(axis=axis)[mask]
	if not inplace:
	return result
	self._update_inplace(result)
	return None

Expected Behavior

IndexLabel | None might should be any array like object.

A similar issue: #48098

Installed Versions

INSTALLED VERSIONS

commit : 91111fd
python : 3.9.12.final.0
python-bits : 64
OS : Darwin
OS-release : 22.1.0
Version : Darwin Kernel Version 22.1.0: Sun Oct 9 20:15:52 PDT 2022; root:xnu-8792.41.9~2/RELEASE_ARM64_T8112
machine : arm64
processor : arm
byteorder : little
LC_ALL : None
LANG : None
LOCALE : None.UTF-8

pandas : 1.5.1
numpy : 1.23.1
pytz : 2022.5
dateutil : 2.8.2
setuptools : 65.5.0
pip : 22.3
Cython : None
pytest : None
hypothesis : None
sphinx : None
blosc : None
feather : None
xlsxwriter : None
lxml.etree : None
html5lib : None
pymysql : None
psycopg2 : None
jinja2 : 3.1.2
IPython : 8.5.0
pandas_datareader: None
bs4 : 4.11.1
bottleneck : 1.3.5
brotli :
fastparquet : None
fsspec : None
gcsfs : None
matplotlib : 3.6.1
numba : None
numexpr : 2.8.3
odfpy : None
openpyxl : None
pandas_gbq : None
pyarrow : None
pyreadstat : None
pyxlsb : None
s3fs : None
scipy : 1.9.3
snappy : None
sqlalchemy : None
tables : None
tabulate : 0.8.10
xarray : None
xlrd : None
xlwt : None
zstandard : None
tzdata : None

[phofl]

Hi,

Thanks for your report. Are you using our stubs? If yes, this should go there too

[stevenlis]

I don't say it in my conda list, so i guess no?

[rhshadrach]

The screenshot looks like VS code, I think that's what is using the stubs even if they aren't in your Python environment. cc @Dr-Irv

[Dr-Irv]

The screenshot looks like VS code, I think that's what is using the stubs even if they aren't in your Python environment. cc @Dr-Irv

Yes, most likely. Microsoft bundles pandas-stubs in their release. You can check that by hovering over dropna(), then right-click and select "go to declaration" and it will pull up a PYI file somewhere in your pylance distribution dist/bundles/stubs/pandas/. If that's the case, then this is an issue for the pandas-stubs project.

If that's the case, please create the issue there.

[stevenlis]

Thanks @rhshadrach @Dr-Irv Indeed it's pylance in vscode... and they do use pandas-stubs. @phofl could you transfer the issue to pandas-stubs?

[phofl]

You have to open another issue in the stubs repo

[Dr-Irv]

Closing this as it is handled in the pandas-stubs.