DEPR: revert enforcing the deprecation of exposing blocks in core.internals and deprecate with FutureWarning (pandas-dev#58715)

Author: natmokval

doc/source/whatsnew/v3.0.0.rst

@@ -481,7 +481,7 @@ Other Removals
 - Enforced deprecation of :meth:`Series.interpolate` and :meth:`DataFrame.interpolate` for object-dtype (:issue:`57820`)
 - Enforced deprecation of :meth:`offsets.Tick.delta`, use ``pd.Timedelta(obj)`` instead (:issue:`55498`)
 - Enforced deprecation of ``axis=None`` acting the same as ``axis=0`` in the DataFrame reductions ``sum``, ``prod``, ``std``, ``var``, and ``sem``, passing ``axis=None`` will now reduce over both axes; this is particularly the case when doing e.g. ``numpy.sum(df)`` (:issue:`21597`)
-- Enforced deprecation of ``core.internals`` members ``Block``, ``ExtensionBlock``, and ``DatetimeTZBlock`` (:issue:`58467`)
+- Enforced deprecation of ``core.internals`` member ``DatetimeTZBlock`` (:issue:`58467`)
 - Enforced deprecation of ``date_parser`` in :func:`read_csv`, :func:`read_table`, :func:`read_fwf`, and :func:`read_excel` in favour of ``date_format`` (:issue:`50601`)
 - Enforced deprecation of ``keep_date_col`` keyword in :func:`read_csv` (:issue:`55569`)
 - Enforced deprecation of ``quantile`` keyword in :meth:`.Rolling.quantile` and :meth:`.Expanding.quantile`, renamed to ``q`` instead. (:issue:`52550`)

pandas/core/internals/__init__.py

@@ -6,8 +6,52 @@
 )
 
 __all__ = [
+    "Block",
+    "ExtensionBlock",
     "make_block",
     "BlockManager",
     "SingleBlockManager",
     "concatenate_managers",
 ]
+
+
+def __getattr__(name: str):
+    # GH#55139
+    import warnings
+
+    if name == "create_block_manager_from_blocks":
+        # GH#33892
+        warnings.warn(
+            f"{name} is deprecated and will be removed in a future version. "
+            "Use public APIs instead.",
+            FutureWarning,
+            # https://github.com/pandas-dev/pandas/pull/55139#pullrequestreview-1720690758
+            # on hard-coding stacklevel
+            stacklevel=2,
+        )
+        from pandas.core.internals.managers import create_block_manager_from_blocks
+
+        return create_block_manager_from_blocks
+
+    if name in [
+        "Block",
+        "ExtensionBlock",
+    ]:
+        warnings.warn(
+            f"{name} is deprecated and will be removed in a future version. "
+            "Use public APIs instead.",
+            FutureWarning,
+            # https://github.com/pandas-dev/pandas/pull/55139#pullrequestreview-1720690758
+            # on hard-coding stacklevel
+            stacklevel=2,
+        )
+        if name == "ExtensionBlock":
+            from pandas.core.internals.blocks import ExtensionBlock
+
+            return ExtensionBlock
+        else:
+            from pandas.core.internals.blocks import Block
+
+            return Block
+
+    raise AttributeError(f"module 'pandas.core.internals' has no attribute '{name}'")

pandas/io/pytables.py

@@ -126,8 +126,7 @@
         npt,
     )
 
-    from pandas.core.internals.blocks import Block
-
+    from pandas.core.internals import Block
 
 # versioning attribute
 _version = "0.15.2"

pandas/tests/internals/test_api.py

@@ -41,6 +41,20 @@ def test_namespace():
     assert set(result) == set(expected + modules)
 
 
+@pytest.mark.parametrize(
+    "name",
+    [
+        "Block",
+        "ExtensionBlock",
+    ],
+)
+def test_deprecations(name):
+    # GH#55139
+    msg = f"{name} is deprecated.* Use public APIs instead"
+    with tm.assert_produces_warning(FutureWarning, match=msg):
+        getattr(internals, name)
+
+
 def test_make_block_2d_with_dti():
     # GH#41168
     dti = pd.date_range("2012", periods=3, tz="UTC")
@@ -53,6 +67,18 @@ def test_make_block_2d_with_dti():
     assert blk.values.shape == (1, 3)
 
 
+def test_create_block_manager_from_blocks_deprecated():
+    # GH#33892
+    # If they must, downstream packages should get this from internals.api,
+    #  not internals.
+    msg = (
+        "create_block_manager_from_blocks is deprecated and will be "
+        "removed in a future version. Use public APIs instead"
+    )
+    with tm.assert_produces_warning(FutureWarning, match=msg):
+        internals.create_block_manager_from_blocks
+
+
 def test_create_dataframe_from_blocks(float_frame):
     block = float_frame._mgr.blocks[0]
     index = float_frame.index.copy()