DOC/DEPR: doc warnings in doc-tests

[jreback]

from a recent doc-build (failure is not related to this issue)

https://github.com/pandas-dev/pandas/runs/4562675953?check_suite_focus=true

I am not entirely sure where these are generated but we should fix in the doc-strings if this where they are coming from.

=============================== warnings summary ===============================
../../../../../usr/share/miniconda/envs/pandas-dev/lib/python3.8/importlib/__init__.py:127
  /usr/share/miniconda/envs/pandas-dev/lib/python3.8/importlib/__init__.py:127: FutureWarning: pandas.core.index is deprecated and will be removed in a future version. The public classes are available in the top-level namespace.
    return _bootstrap._gcd_import(name[level:], package, level)

pandas/core/generic.py::pandas.core.generic.NDFrame.empty
  <doctest pandas.core.generic.NDFrame.empty[10]>:1: FutureWarning: The default dtype for empty Series will be 'object' instead of 'float64' in a future version. Specify a dtype explicitly to silence this warning.

pandas/core/generic.py::pandas.core.generic.NDFrame.xs
  <doctest pandas.core.generic.NDFrame.xs[5]>:1: PerformanceWarning: indexing past lexsort depth may impact performance.

pandas/core/arrays/categorical.py::pandas.core.arrays.categorical.Categorical.replace
  <doctest pandas.core.arrays.categorical.Categorical.replace[1]>:1: FutureWarning: Categorical.replace is deprecated and will be removed in a future version. Use Series.replace directly instead.

pandas/core/dtypes/common.py::pandas.core.dtypes.common.is_categorical
  <doctest pandas.core.dtypes.common.is_categorical[0]>:1: FutureWarning: is_categorical is deprecated and will be removed in a future version. Use is_categorical_dtype instead.

pandas/core/dtypes/common.py::pandas.core.dtypes.common.is_categorical
  <doctest pandas.core.dtypes.common.is_categorical[2]>:1: FutureWarning: is_categorical is deprecated and will be removed in a future version. Use is_categorical_dtype instead.

pandas/core/dtypes/common.py::pandas.core.dtypes.common.is_categorical
  <doctest pandas.core.dtypes.common.is_categorical[4]>:1: FutureWarning: is_categorical is deprecated and will be removed in a future version. Use is_categorical_dtype instead.

pandas/core/dtypes/common.py::pandas.core.dtypes.common.is_extension_type
  <doctest pandas.core.dtypes.common.is_extension_type[0]>:1: FutureWarning: 'is_extension_type' is deprecated and will be removed in a future version.  Use 'is_extension_array_dtype' instead.

pandas/core/dtypes/common.py::pandas.core.dtypes.common.is_extension_type
  <doctest pandas.core.dtypes.common.is_extension_type[3]>:1: FutureWarning: 'is_extension_type' is deprecated and will be removed in a future version.  Use 'is_extension_array_dtype' instead.

pandas/core/groupby/generic.py::pandas.core.groupby.generic.DataFrameGroupBy.transform
  <doctest pandas.core.groupby.generic.DataFrameGroupBy.transform[2]>:1: FutureWarning: Dropping invalid columns in DataFrameGroupBy.transform is deprecated. In a future version, a TypeError will be raised. Before calling .transform, select only columns which should be valid for the function.

pandas/core/groupby/generic.py::pandas.core.groupby.generic.DataFrameGroupBy.transform
  <doctest pandas.core.groupby.generic.DataFrameGroupBy.transform[3]>:1: FutureWarning: Dropping invalid columns in DataFrameGroupBy.transform is deprecated. In a future version, a TypeError will be raised. Before calling .transform, select only columns which should be valid for the function.

pandas/core/groupby/generic.py::pandas.core.groupby.generic.SeriesGroupBy.transform
  <doctest pandas.core.groupby.generic.SeriesGroupBy.transform[2]>:1: FutureWarning: Dropping invalid columns in DataFrameGroupBy.transform is deprecated. In a future version, a TypeError will be raised. Before calling .transform, select only columns which should be valid for the function.

pandas/core/groupby/generic.py::pandas.core.groupby.generic.SeriesGroupBy.transform
  <doctest pandas.core.groupby.generic.SeriesGroupBy.transform[3]>:1: FutureWarning: Dropping invalid columns in DataFrameGroupBy.transform is deprecated. In a future version, a TypeError will be raised. Before calling .transform, select only columns which should be valid for the function.

pandas/core/indexes/accessors.py::pandas.core.indexes.accessors.DatetimeProperties.isocalendar
  <doctest pandas.core.indexes.accessors.DatetimeProperties.isocalendar[0]>:1: FutureWarning: Inferring datetime64[ns] from data containing strings is deprecated and will be removed in a future version. To retain the old behavior explicitly pass Series(data, dtype=datetime64[ns])

pandas/core/indexes/base.py::pandas.core.indexes.base.Index.equals
  <doctest pandas.core.indexes.base.Index.equals[11]>:1: FutureWarning: pandas.Int64Index is deprecated and will be removed from pandas in a future version. Use pandas.NumericIndex with the appropriate dtype instead.

pandas/core/indexes/base.py::pandas.core.indexes.base.Index.equals
  <doctest pandas.core.indexes.base.Index.equals[13]>:1: FutureWarning: pandas.UInt64Index is deprecated and will be removed from pandas in a future version. Use pandas.NumericIndex with the appropriate dtype instead.

pandas/core/indexes/base.py::pandas.core.indexes.base.Index.is_mixed
  <doctest pandas.core.indexes.base.Index.is_mixed[1]>:1: FutureWarning: Index.is_mixed is deprecated and will be removed in a future version. Check index.inferred_type directly instead.

pandas/core/indexes/datetimes.py::pandas.core.indexes.datetimes.date_range
  <doctest pandas.core.indexes.datetimes.date_range[8]>:1: FutureWarning: Argument `closed` is deprecated in favor of `inclusive`.

pandas/core/indexes/multi.py::pandas.core.indexes.multi.MultiIndex._is_lexsorted
  <doctest pandas.core.indexes.multi.MultiIndex._is_lexsorted[0]>:1: FutureWarning: MultiIndex.is_lexsorted is deprecated as a public function, users should use MultiIndex.is_monotonic_increasing instead.

pandas/core/indexes/multi.py::pandas.core.indexes.multi.MultiIndex._is_lexsorted
  <doctest pandas.core.indexes.multi.MultiIndex._is_lexsorted[1]>:1: FutureWarning: MultiIndex.is_lexsorted is deprecated as a public function, users should use MultiIndex.is_monotonic_increasing instead.

pandas/core/indexes/multi.py::pandas.core.indexes.multi.MultiIndex._is_lexsorted
  <doctest pandas.core.indexes.multi.MultiIndex._is_lexsorted[2]>:1: FutureWarning: MultiIndex.is_lexsorted is deprecated as a public function, users should use MultiIndex.is_monotonic_increasing instead.

pandas/core/indexes/multi.py::pandas.core.indexes.multi.MultiIndex._is_lexsorted
  <doctest pandas.core.indexes.multi.MultiIndex._is_lexsorted[3]>:1: FutureWarning: MultiIndex.is_lexsorted is deprecated as a public function, users should use MultiIndex.is_monotonic_increasing instead.

pandas/core/indexes/multi.py::pandas.core.indexes.multi.MultiIndex._is_lexsorted
  <doctest pandas.core.indexes.multi.MultiIndex._is_lexsorted[4]>:1: FutureWarning: MultiIndex.is_lexsorted is deprecated as a public function, users should use MultiIndex.is_monotonic_increasing instead.

pandas/core/indexes/multi.py::pandas.core.indexes.multi.MultiIndex._is_lexsorted
  <doctest pandas.core.indexes.multi.MultiIndex._is_lexsorted[5]>:1: FutureWarning: MultiIndex.is_lexsorted is deprecated as a public function, users should use MultiIndex.is_monotonic_increasing instead.

pandas/core/ops/missing.py::pandas.core.ops.missing.mask_zero_div_zero
  <doctest pandas.core.ops.missing.mask_zero_div_zero[3]>:1: RuntimeWarning: divide by zero encountered in floor_divide

pandas/core/window/rolling.py::pandas.core.window.rolling.Rolling.count
  <doctest pandas.core.window.rolling.Rolling.count[1]>:1: FutureWarning: min_periods=None will default to the size of window consistent with other methods in a future version. Specify min_periods=0 instead.

[jreback]

cc @pandas-dev/pandas-core

[mroeschke]

Is this the same as #44642?

[jreback]

yup