CLN: remove FloatBlock, share _can_hold_na (#40526)

Author: jbrockmendel

pandas/core/internals/__init__.py

@@ -12,7 +12,6 @@
     DatetimeBlock,
     DatetimeTZBlock,
     ExtensionBlock,
-    FloatBlock,
     NumericBlock,
     ObjectBlock,
     TimeDeltaBlock,
@@ -31,7 +30,6 @@
     "DatetimeBlock",
     "DatetimeTZBlock",
     "ExtensionBlock",
-    "FloatBlock",
     "ObjectBlock",
     "TimeDeltaBlock",
     "make_block",

pandas/core/internals/blocks.py

@@ -157,7 +157,6 @@ class Block(PandasObject):
     is_bool = False
     is_object = False
     is_extension = False
-    _can_hold_na = False
     _can_consolidate = True
     _validate_ndim = True
 
@@ -212,6 +211,17 @@ def is_view(self) -> bool:
         values = cast(np.ndarray, values)
         return values.base is not None
 
+    @final
+    @property
+    def _can_hold_na(self) -> bool:
+        """
+        Can we store NA values in this Block?
+        """
+        values = self.values
+        if isinstance(values, np.ndarray):
+            return values.dtype.kind not in ["b", "i", "u"]
+        return values._can_hold_na
+
     @final
     @property
     def is_categorical(self) -> bool:
@@ -1504,11 +1514,6 @@ def _holder(self):
         # For extension blocks, the holder is values-dependent.
         return type(self.values)
 
-    @property
-    def _can_hold_na(self):
-        # The default ExtensionArray._can_hold_na is True
-        return self._holder._can_hold_na
-
     @property
     def is_view(self) -> bool:
         """Extension arrays are never treated as views."""
@@ -1787,19 +1792,11 @@ def _can_hold_element(self, element: Any) -> bool:
         # "Union[dtype[Any], ExtensionDtype]"; expected "dtype[Any]"
         return can_hold_element(self.dtype, element)  # type: ignore[arg-type]
 
-    @property
-    def _can_hold_na(self):
-        return self.dtype.kind not in ["b", "i", "u"]
-
     @property
     def is_bool(self):
         return self.dtype.kind == "b"
 
 
-class FloatBlock(NumericBlock):
-    __slots__ = ()
-
-
 class NDArrayBackedExtensionBlock(HybridMixin, Block):
     """
     Block backed by an NDArrayBackedExtensionArray
@@ -1909,7 +1906,6 @@ class DatetimeLikeBlockMixin(NDArrayBackedExtensionBlock):
     """Mixin class for DatetimeBlock, DatetimeTZBlock, and TimedeltaBlock."""
 
     is_numeric = False
-    _can_hold_na = True
 
     def array_values(self):
         return ensure_wrapped_if_datetimelike(self.values)
@@ -1938,7 +1934,6 @@ class DatetimeTZBlock(ExtensionBlock, DatetimeBlock):
 
     __slots__ = ()
     is_extension = True
-    _can_hold_na = True
     is_numeric = False
 
     internal_values = Block.internal_values
@@ -1970,7 +1965,6 @@ class TimeDeltaBlock(DatetimeLikeBlockMixin):
 class ObjectBlock(Block):
     __slots__ = ()
     is_object = True
-    _can_hold_na = True
 
     values: np.ndarray
 
@@ -2109,9 +2103,7 @@ def get_block_type(values, dtype: Optional[Dtype] = None):
         cls = DatetimeBlock
     elif kind == "m":
         cls = TimeDeltaBlock
-    elif kind == "f":
-        cls = FloatBlock
-    elif kind in ["c", "i", "u", "b"]:
+    elif kind in ["f", "c", "i", "u", "b"]:
         cls = NumericBlock
     else:
         cls = ObjectBlock

pandas/core/internals/managers.py

@@ -1839,13 +1839,9 @@ def _form_blocks(
         items_dict[block_type.__name__].append((i, v))
 
     blocks: List[Block] = []
-    if len(items_dict["FloatBlock"]):
-        float_blocks = _multi_blockify(items_dict["FloatBlock"])
-        blocks.extend(float_blocks)
-
     if len(items_dict["NumericBlock"]):
-        complex_blocks = _multi_blockify(items_dict["NumericBlock"])
-        blocks.extend(complex_blocks)
+        numeric_blocks = _multi_blockify(items_dict["NumericBlock"])
+        blocks.extend(numeric_blocks)
 
     if len(items_dict["TimeDeltaBlock"]):
         timedelta_blocks = _multi_blockify(items_dict["TimeDeltaBlock"])

pandas/tests/extension/test_external_block.py

@@ -14,7 +14,9 @@
 class CustomBlock(ExtensionBlock):
 
     _holder = np.ndarray
-    _can_hold_na = False
+    # error: Cannot override final attribute "_can_hold_na"
+    # (previously declared in base class "Block")
+    _can_hold_na = False  # type: ignore[misc]
 
 
 @pytest.fixture

pandas/tests/internals/test_api.py

@@ -30,7 +30,6 @@ def test_namespace():
         "DatetimeBlock",
         "DatetimeTZBlock",
         "ExtensionBlock",
-        "FloatBlock",
         "ObjectBlock",
         "TimeDeltaBlock",
         "make_block",