Merge branch 'main' into doc-update-rolling-example

Author: balaraj74

.github/workflows/unit-tests.yml

@@ -358,8 +358,6 @@ jobs:
 
       - name: Run Tests
         uses: ./.github/actions/run-tests
-        # TEMP allow this to fail until we fixed all test failures (related to chained assignment warnings)
-        continue-on-error: true
 
   # NOTE: this job must be kept in sync with the Pyodide build job in wheels.yml
   emscripten:

.github/workflows/wheels.yml

@@ -101,7 +101,7 @@ jobs:
         - [macos-14, macosx_arm64]
         - [windows-2022, win_amd64]
         - [windows-11-arm, win_arm64]
-        python: [["cp311", "3.11"], ["cp312", "3.12"], ["cp313", "3.13"], ["cp313t", "3.13"]]
+        python: [["cp311", "3.11"], ["cp312", "3.12"], ["cp313", "3.13"], ["cp313t", "3.13"], ["cp314", "3.14"], ["cp314t", "3.14"]]
         include:
         # Build Pyodide wheels and upload them to Anaconda.org
         # NOTE: this job is similar to the one in unit-tests.yml except for the fact

doc/source/development/contributing_codebase.rst

@@ -214,7 +214,8 @@ With custom types and inference this is not always possible so exceptions are ma
 pandas-specific types
 ~~~~~~~~~~~~~~~~~~~~~
 
-Commonly used types specific to pandas will appear in `pandas._typing <https://github.com/pandas-dev/pandas/blob/main/pandas/_typing.py>`_ and you should use these where applicable. This module is private for now but ultimately this should be exposed to third party libraries who want to implement type checking against pandas.
+Commonly used types specific to pandas will appear in `pandas._typing <https://github.com/pandas-dev/pandas/blob/main/pandas/_typing.py>`__ and you should use these where applicable. This module is private and is meant for pandas development.
+Types that are meant for user consumption should be exposed in `pandas.api.typing.aliases <https://github.com/pandas-dev/pandas/blob/main/pandas/api/typing/aliases.py>`__ and ideally added to the `pandas-stubs <https://github.com/pandas-dev/pandas-stubs>`__ project.
 
 For example, quite a few functions in pandas accept a ``dtype`` argument. This can be expressed as a string like ``"object"``, a ``numpy.dtype`` like ``np.int64`` or even a pandas ``ExtensionDtype`` like ``pd.CategoricalDtype``. Rather than burden the user with having to constantly annotate all of those options, this can simply be imported and reused from the pandas._typing module
 

doc/source/getting_started/index.rst

@@ -527,7 +527,6 @@ Data sets often contain more than just numerical data. pandas provides a wide ra
                 </div>
             </div>
         </div>
-
     </div>
     </div>
 

doc/source/getting_started/intro_tutorials/03_subset_data.rst

@@ -54,6 +54,8 @@ I’m interested in the age of the Titanic passengers.
 To select a single column, use square brackets ``[]`` with the column
 name of the column of interest.
 
+For more explanation, see `Brackets in Python and pandas <https://python-public-policy.afeld.me/en/columbia/brackets.html>`__.
+
 .. raw:: html
 
         </li>

doc/source/reference/aliases.rst

@@ -0,0 +1,96 @@
+{{ header }}
+
+.. _api.typing.aliases:
+
+======================================
+pandas typing aliases
+======================================
+
+**************
+Typing aliases
+**************
+
+.. currentmodule:: pandas.api.typing.aliases
+
+The typing declarations in ``pandas/_typing.py`` are considered private, and used
+by pandas developers for type checking of the pandas code base.  For users, it is
+highly recommended to use the ``pandas-stubs`` package that represents the officially
+supported type declarations for users of pandas.
+They are documented here for users who wish to use these declarations in their
+own python code that calls pandas or expects certain results.
+
+.. warning::
+
+    Note that the definitions and use cases of these aliases are subject to change without notice in any major, minor, or patch release of pandas.
+
+Each of these aliases listed in the table below can be found by importing them from :py:mod:`pandas.api.typing.aliases`.
+
+==================================== ================================================================
+Alias                                Meaning
+==================================== ================================================================
+:py:type:`AggFuncType`               Type of functions that can be passed to :meth:`agg` methods
+:py:type:`AlignJoin`                 Argument type for ``join`` in :meth:`DataFrame.join`
+:py:type:`AnyAll`                    Argument type for ``how`` in :meth:`dropna`
+:py:type:`AnyArrayLike`              Used to represent :class:`ExtensionArray`, ``numpy`` arrays, :class:`Index` and :class:`Series`
+:py:type:`ArrayLike`                 Used to represent :class:`ExtensionArray`, ``numpy`` arrays
+:py:type:`AstypeArg`                 Argument type in :meth:`astype`
+:py:type:`Axes`                      :py:type:`AnyArrayLike` plus sequences (not strings) and ``range``
+:py:type:`Axis`                      Argument type for ``axis`` in many methods
+:py:type:`CSVEngine`                 Argument type for ``engine`` in :meth:`DataFrame.read_csv`
+:py:type:`ColspaceArgType`           Argument type for ``colspace`` in :meth:`DataFrame.to_html`
+:py:type:`CompressionOptions`        Argument type for ``compression`` in all I/O output methods except :meth:`DataFrame.to_parquet`
+:py:type:`CorrelationMethod`         Argument type for ``correlation`` in :meth:`corr`
+:py:type:`DropKeep`                  Argument type for ``keep`` in :meth:`drop_duplicates`
+:py:type:`Dtype`                     Types as objects that can be used to specify dtypes
+:py:type:`DtypeArg`                  Argument type for ``dtype`` in various methods
+:py:type:`DtypeBackend`              Argument type for ``dtype_backend`` in various methods
+:py:type:`DtypeObj`                  Numpy dtypes and Extension dtypes
+:py:type:`ExcelWriterIfSheetExists`  Argument type for ``if_sheet_exists`` in :class:`ExcelWriter`
+:py:type:`ExcelWriterMergeCells`     Argument type for ``merge_cells`` in :meth:`to_excel`
+:py:type:`FilePath`                  Type of paths for files for I/O methods
+:py:type:`FillnaOptions`             Argument type for ``method`` in various methods where NA values are filled
+:py:type:`FloatFormatType`           Argument type for ``float_format`` in :meth:`to_string`
+:py:type:`FormattersType`            Argument type for ``formatters`` in :meth:`to_string`
+:py:type:`FromDictOrient`            Argument type for ``orient`` in :meth:`DataFrame.from_dict`
+:py:type:`HTMLFlavors`               Argument type for ``flavor`` in :meth:`pandas.read_html`
+:py:type:`IgnoreRaise`               Argument type for ``errors`` in multiple methods
+:py:type:`IndexLabel`                Argument type for ``level`` in multiple methods
+:py:type:`InterpolateOptions`        Argument type for ``interpolate`` in :meth:`interpolate`
+:py:type:`JSONEngine`                Argument type for ``engine`` in :meth:`read_json`
+:py:type:`JSONSerializable`          Argument type for the return type of a callable for argument ``default_handler`` in :meth:`to_json`
+:py:type:`JoinHow`                   Argument type for ``how`` in :meth:`pandas.merge_ordered` and for ``join`` in :meth:`Series.align`
+:py:type:`JoinValidate`              Argument type for ``validate`` in :meth:`DataFrame.join`
+:py:type:`MergeHow`                  Argument type for ``how`` in :meth:`merge`
+:py:type:`MergeValidate`             Argument type for ``validate`` in :meth:`merge`
+:py:type:`NaPosition`                Argument type for ``na_position`` in :meth:`sort_index` and :meth:`sort_values`
+:py:type:`NsmallestNlargestKeep`     Argument type for ``keep`` in :meth:`nlargest` and :meth:`nsmallest`
+:py:type:`OpenFileErrors`            Argument type for ``errors`` in :meth:`to_hdf` and :meth:`to_csv`
+:py:type:`Ordered`                   Return type for :py:attr:`ordered`` in :class:`CategoricalDtype` and :class:`Categorical`
+:py:type:`ParquetCompressionOptions` Argument type for ``compression`` in :meth:`DataFrame.to_parquet`
+:py:type:`QuantileInterpolation`     Argument type for ``interpolation`` in :meth:`quantile`
+:py:type:`ReadBuffer`                Additional argument type corresponding to buffers for various file reading methods
+:py:type:`ReadCsvBuffer`             Additional argument type corresponding to buffers for :meth:`pandas.read_csv`
+:py:type:`ReadPickleBuffer`          Additional argument type corresponding to buffers for :meth:`pandas.read_pickle`
+:py:type:`ReindexMethod`             Argument type for ``reindex`` in :meth:`reindex`
+:py:type:`Scalar`                    Types that can be stored in :class:`Series` with non-object dtype
+:py:type:`SequenceNotStr`            Used for arguments that require sequences, but not plain strings
+:py:type:`SliceType`                 Argument types for ``start`` and ``end`` in :meth:`Index.slice_locs`
+:py:type:`SortKind`                  Argument type for ``kind`` in :meth:`sort_index` and :meth:`sort_values`
+:py:type:`StorageOptions`            Argument type for ``storage_options`` in various file output methods
+:py:type:`Suffixes`                  Argument type for ``suffixes`` in :meth:`merge`, :meth:`compare` and :meth:`merge_ordered`
+:py:type:`TakeIndexer`               Argument type for ``indexer`` and ``indices`` in :meth:`take`
+:py:type:`TimeAmbiguous`             Argument type for ``ambiguous`` in time operations
+:py:type:`TimeGrouperOrigin`         Argument type for ``origin`` in :meth:`resample` and :class:`TimeGrouper`
+:py:type:`TimeNonexistent`           Argument type for ``nonexistent`` in time operations
+:py:type:`TimeUnit`                  Time unit argument and return type for :py:attr:`unit`, arguments ``unit`` and ``date_unit``
+:py:type:`TimedeltaConvertibleTypes` Argument type for ``offset`` in :meth:`resample`, ``halflife`` in :meth:`ewm` and ``start`` and ``end`` in :meth:`pandas.timedelta_range`
+:py:type:`TimestampConvertibleTypes` Argument type for ``origin`` in :meth:`resample` and :meth:`pandas.to_datetime`
+:py:type:`ToStataByteorder`          Argument type for ``byteorder`` in :meth:`DataFrame.to_stata`
+:py:type:`ToTimestampHow`            Argument type for ``how`` in :meth:`to_timestamp` and ``convention`` in :meth:`resample`
+:py:type:`UpdateJoin`                Argument type for ``join`` in :meth:`DataFrame.update`
+:py:type:`UsecolsArgType`            Argument type for ``usecols`` in :meth:`pandas.read_clipboard`, :meth:`pandas.read_csv` and :meth:`pandas.read_excel`
+:py:type:`WindowingRankType`         Argument type for ``method`` in :meth:`rank`` in rolling and expanding window operations
+:py:type:`WriteBuffer`               Additional argument type corresponding to buffers for various file output methods
+:py:type:`WriteExcelBuffer`          Additional argument type corresponding to buffers for :meth:`to_excel`
+:py:type:`XMLParsers`                Argument type for ``parser`` in :meth:`DataFrame.to_xml` and :meth:`pandas.read_xml`
+==================================== ================================================================

doc/source/reference/index.rst

@@ -55,6 +55,7 @@ to be stable.
    extensions
    testing
    missing_value
+   aliases
 
 .. This is to prevent warnings in the doc build. We don't want to encourage
 .. these methods.

doc/source/whatsnew/v3.0.0.rst

@@ -220,6 +220,7 @@ Other enhancements
 - Implemented :meth:`Series.str.isascii` and :meth:`Series.str.isascii` (:issue:`59091`)
 - Improve the resulting dtypes in :meth:`DataFrame.where` and :meth:`DataFrame.mask` with :class:`ExtensionDtype` ``other`` (:issue:`62038`)
 - Improved deprecation message for offset aliases (:issue:`60820`)
+- Many type aliases are now exposed in the new submodule :py:mod:`pandas.api.typing.aliases` (:issue:`55231`)
 - Multiplying two :class:`DateOffset` objects will now raise a ``TypeError`` instead of a ``RecursionError`` (:issue:`59442`)
 - Restore support for reading Stata 104-format and enable reading 103-format dta files (:issue:`58554`)
 - Support passing a :class:`Iterable[Hashable]` input to :meth:`DataFrame.drop_duplicates` (:issue:`59237`)
@@ -603,6 +604,7 @@ Other API changes
   an empty ``RangeIndex`` or empty ``Index`` with object dtype when determining
   the dtype of the resulting Index (:issue:`60797`)
 - :class:`IncompatibleFrequency` now subclasses ``TypeError`` instead of ``ValueError``. As a result, joins with mismatched frequencies now cast to object like other non-comparable joins, and arithmetic with indexes with mismatched frequencies align (:issue:`55782`)
+- :meth:`CategoricalIndex.append` no longer attempts to cast different-dtype indexes to the caller's dtype (:issue:`41626`)
 - :meth:`ExtensionDtype.construct_array_type` is now a regular method instead of a ``classmethod`` (:issue:`58663`)
 - Comparison operations between :class:`Index` and :class:`Series` now consistently return :class:`Series` regardless of which object is on the left or right (:issue:`36759`)
 - Numpy functions like ``np.isinf`` that return a bool dtype when called on a :class:`Index` object now return a bool-dtype :class:`Index` instead of ``np.ndarray`` (:issue:`52676`)
@@ -974,8 +976,8 @@ Indexing
 - Bug in reindexing of :class:`DataFrame` with :class:`PeriodDtype` columns in case of consolidated block (:issue:`60980`, :issue:`60273`)
 - Bug in :meth:`DataFrame.loc.__getitem__` and :meth:`DataFrame.iloc.__getitem__` with a :class:`CategoricalDtype` column with integer categories raising when trying to index a row containing a ``NaN`` entry (:issue:`58954`)
 - Bug in :meth:`Index.__getitem__` incorrectly raising with a 0-dim ``np.ndarray`` key (:issue:`55601`)
+- Bug in adding new rows with :meth:`DataFrame.loc.__setitem__` or :class:`Series.loc.__setitem__` which failed to retain dtype on the object's index in some cases (:issue:`41626`)
 - Bug in indexing on a :class:`DatetimeIndex` with a ``timestamp[pyarrow]`` dtype or on a :class:`TimedeltaIndex` with a ``duration[pyarrow]`` dtype (:issue:`62277`)
--
 
 Missing
 ^^^^^^^
@@ -1094,7 +1096,7 @@ Reshaping
 - Bug in :func:`melt` where calling with duplicate column names in ``id_vars`` raised a misleading ``AttributeError`` (:issue:`61475`)
 - Bug in :meth:`DataFrame.merge` where user-provided suffixes could result in duplicate column names if the resulting names matched existing columns. Now raises a :class:`MergeError` in such cases. (:issue:`61402`)
 - Bug in :meth:`DataFrame.merge` with :class:`CategoricalDtype` columns incorrectly raising ``RecursionError`` (:issue:`56376`)
--
+- Bug in :meth:`DataFrame.merge` with a ``float32`` index incorrectly casting the index to ``float64`` (:issue:`41626`)
 
 Sparse
 ^^^^^^

pandas/_testing/contexts.py

@@ -12,7 +12,10 @@
 )
 import uuid
 
-from pandas.compat import PYPY
+from pandas.compat import (
+    PYPY,
+    WARNING_CHECK_DISABLED,
+)
 from pandas.errors import ChainedAssignmentError
 
 from pandas.io.common import get_handle
@@ -163,7 +166,7 @@ def with_csv_dialect(name: str, **kwargs) -> Generator[None]:
 def raises_chained_assignment_error(extra_warnings=(), extra_match=()):
     from pandas._testing import assert_produces_warning
 
-    if PYPY:
+    if PYPY or WARNING_CHECK_DISABLED:
         if not extra_warnings:
             from contextlib import nullcontext
 

pandas/_typing.py

@@ -133,8 +133,27 @@ def __reversed__(self) -> Iterator[_T_co]: ...
 
 PythonScalar: TypeAlias = str | float | bool
 DatetimeLikeScalar: TypeAlias = Union["Period", "Timestamp", "Timedelta"]
-PandasScalar: TypeAlias = Union["Period", "Timestamp", "Timedelta", "Interval"]
-Scalar: TypeAlias = PythonScalar | PandasScalar | np.datetime64 | np.timedelta64 | date
+
+# aligned with pandas-stubs - typical scalars found in Series.  Explicitly leaves
+# out object
+_IndexIterScalar: TypeAlias = Union[
+    str,
+    bytes,
+    date,
+    datetime,
+    timedelta,
+    np.datetime64,
+    np.timedelta64,
+    bool,
+    int,
+    float,
+    "Timestamp",
+    "Timedelta",
+]
+Scalar: TypeAlias = Union[
+    _IndexIterScalar, "Interval", complex, np.integer, np.floating, np.complexfloating
+]
+
 IntStrT = TypeVar("IntStrT", bound=int | str)
 
 # timestamp and timedelta convertible types
@@ -312,6 +331,9 @@ def closed(self) -> bool:
 CompressionOptions: TypeAlias = (
     Literal["infer", "gzip", "bz2", "zip", "xz", "zstd", "tar"] | CompressionDict | None
 )
+ParquetCompressionOptions: TypeAlias = (
+    Literal["snappy", "gzip", "brotli", "lz4", "zstd"] | None
+)
 
 # types in DataFrameFormatter
 FormattersType: TypeAlias = (