feat(pandas,dask): support quarter truncation

ibis/backends/dask/executor.py

@@ -7,7 +7,6 @@
 import dask.dataframe as dd
 import numpy as np
 import pandas as pd
-from packaging.version import parse as vparse
 
 import ibis.backends.dask.kernels as dask_kernels
 import ibis.expr.operations as ops
@@ -97,23 +96,6 @@ def mapper(df, cases, results, default):
 
         return cls.partitionwise(mapper, kwargs, name=op.name, dtype=dtype)
 
-    @classmethod
-    def visit(cls, op: ops.TimestampTruncate | ops.DateTruncate, arg, unit):
-        # TODO(kszucs): should use serieswise()
-        if vparse(pd.__version__) >= vparse("2.2"):
-            units = {"m": "min"}
-        else:
-            units = {"m": "Min", "ms": "L"}
-
-        unit = units.get(unit.short, unit.short)
-
-        if unit in "YMWD":
-            return arg.dt.to_period(unit).dt.to_timestamp()
-        try:
-            return arg.dt.floor(unit)
-        except ValueError:
-            return arg.dt.to_period(unit).dt.to_timestamp()
-
     @classmethod
     def visit(cls, op: ops.IntervalFromInteger, unit, **kwargs):
         if unit.short in {"Y", "Q", "M", "W"}:

ibis/backends/pandas/executor.py

@@ -185,7 +185,7 @@ def visit(cls, op: ops.TimestampTruncate | ops.DateTruncate, arg, unit):
 
         unit = units.get(unit.short, unit.short)
 
-        if unit in "YMWD":
+        if unit in "YQMWD":
             return arg.dt.to_period(unit).dt.to_timestamp()
         try:
             return arg.dt.floor(unit)