Fix test, remove DatetimeTZBlock._slice

Author: jbrockmendel

pandas/core/internals/blocks.py

@@ -2240,6 +2240,7 @@ class DatetimeTZBlock(ExtensionBlock, DatetimeBlock):
     to_native_types = DatetimeBlock.to_native_types
     fill_value = np.datetime64("NaT", "ns")
     should_store = DatetimeBlock.should_store
+    _slice = ExtensionBlock._slice
 
     @property
     def _holder(self):
@@ -2307,15 +2308,6 @@ def get_values(self, dtype=None):
             values = values.reshape(1, -1)
         return values
 
-    def _slice(self, slicer):
-        """ return a slice of my values """
-        if isinstance(slicer, tuple):
-            col, loc = slicer
-            if not com.is_null_slice(col) and col != 0:
-                raise IndexError(f"{self} only contains one item")
-            return self.values[loc]
-        return self.values[slicer]
-
     def diff(self, n: int, axis: int = 0) -> List["Block"]:
         """
         1st discrete difference.

pandas/tests/extension/base/getitem.py

@@ -40,8 +40,8 @@ def test_iloc_frame(self, data):
         result = df.iloc[:4, 0]
         self.assert_series_equal(result, expected)
 
-        # GH#32957 null slice along index, slice along rows
-        result = df.iloc[:, :1]
+        # GH#32957 null slice along index, slice along columns with single-block
+        result = df[["A"]].iloc[:, :1]
         self.assert_frame_equal(result, df[["A"]])
 
     def test_loc_series(self, data):