CLN: de-kludge Block.quantile (pandas-dev#27627)

Author: jbrockmendel

pandas/core/internals/blocks.py

@@ -1526,18 +1526,7 @@ def quantile(self, qs, interpolation="linear", axis=0):
         # We should always have ndim == 2 becase Series dispatches to DataFrame
         assert self.ndim == 2
 
-        if self.is_datetimetz:
-            # TODO: cleanup this special case.
-            # We need to operate on i8 values for datetimetz
-            # but `Block.get_values()` returns an ndarray of objects
-            # right now. We need an API for "values to do numeric-like ops on"
-            values = self.values.view("M8[ns]")
-
-            # TODO: NonConsolidatableMixin shape
-            # Usual shape inconsistencies for ExtensionBlocks
-            values = values[None, :]
-        else:
-            values = self.get_values()
+        values = self.get_values()
 
         is_empty = values.shape[axis] == 0
         orig_scalar = not is_list_like(qs)
@@ -1576,7 +1565,6 @@ def quantile(self, qs, interpolation="linear", axis=0):
             result = lib.item_from_zerodim(result)
 
         ndim = getattr(result, "ndim", None) or 0
-        result = self._try_coerce_result(result)
         return make_block(result, placement=np.arange(len(result)), ndim=ndim)
 
     def _replace_coerce(
@@ -2477,21 +2465,9 @@ def _try_coerce_result(self, result):
                 result = self._holder._from_sequence(
                     result.astype(np.int64), freq=None, dtype=self.values.dtype
                 )
-            elif result.dtype == "M8[ns]":
-                # otherwise we get here via quantile and already have M8[ns]
-                result = self._holder._simple_new(
-                    result, freq=None, dtype=self.values.dtype
-                )
 
-        elif isinstance(result, np.datetime64):
-            # also for post-quantile
-            result = self._box_func(result)
         return result
 
-    @property
-    def _box_func(self):
-        return lambda x: tslibs.Timestamp(x, tz=self.dtype.tz)
-
     def diff(self, n, axis=0):
         """1st discrete difference
 
@@ -2564,6 +2540,19 @@ def equals(self, other):
             return False
         return (self.values.view("i8") == other.values.view("i8")).all()
 
+    def quantile(self, qs, interpolation="linear", axis=0):
+        naive = self.values.view("M8[ns]")
+
+        # kludge for 2D block with 1D values
+        naive = naive.reshape(self.shape)
+
+        blk = self.make_block(naive)
+        res_blk = blk.quantile(qs, interpolation=interpolation, axis=axis)
+
+        # ravel is kludge for 2D block with 1D values, assumes column-like
+        aware = self._holder(res_blk.values.ravel(), dtype=self.dtype)
+        return self.make_block_same_class(aware, ndim=res_blk.ndim)
+
 
 class TimeDeltaBlock(DatetimeLikeBlockMixin, IntBlock):
     __slots__ = ()