templatize timedelta arith ops (#19871)

Author: jbrockmendel

pandas/_libs/tslibs/timedeltas.pyx

@@ -471,9 +471,12 @@ def _binary_op_method_timedeltalike(op, name):
  # define a binary operation that only works if the other argument is
  # timedelta like or an array of timedeltalike
  def f(self, other):
- if hasattr(other, 'delta') and not PyDelta_Check(other):
- # offsets.Tick
- return op(self, other.delta)
+ if hasattr(other, '_typ'):
+ # Series, DataFrame, ...
+ if other._typ == 'dateoffset' and hasattr(other, 'delta'):
+ # Tick offset
+ return op(self, other.delta)
+ return NotImplemented
 
  elif other is NaT:
  return NaT
@@ -1052,7 +1055,14 @@ class Timedelta(_Timedelta):
  __rsub__ = _binary_op_method_timedeltalike(lambda x, y: y - x, '__rsub__')
 
  def __mul__(self, other):
- if hasattr(other, 'dtype'):
+ if hasattr(other, '_typ'):
+ # Series, DataFrame, ...
+ if other._typ == 'dateoffset' and hasattr(other, 'delta'):
+ # Tick offset; this op will raise TypeError
+ return other.delta * self
+ return NotImplemented
+
+ elif hasattr(other, 'dtype'):
  # ndarray-like
  return other * self.to_timedelta64()
 
@@ -1068,7 +1078,18 @@ class Timedelta(_Timedelta):
  __rmul__ = __mul__
 
  def __truediv__(self, other):
- if hasattr(other, 'dtype'):
+ if hasattr(other, '_typ'):
+ # Series, DataFrame, ...
+ if other._typ == 'dateoffset' and hasattr(other, 'delta'):
+ # Tick offset
+ return self / other.delta
+ return NotImplemented
+
+ elif is_timedelta64_object(other):
+ # convert to Timedelta below
+ pass
+
+ elif hasattr(other, 'dtype'):
  return self.to_timedelta64() / other
 
  elif is_integer_object(other) or is_float_object(other):
@@ -1084,7 +1105,18 @@ class Timedelta(_Timedelta):
  return self.value / float(other.value)
 
  def __rtruediv__(self, other):
- if hasattr(other, 'dtype'):
+ if hasattr(other, '_typ'):
+ # Series, DataFrame, ...
+ if other._typ == 'dateoffset' and hasattr(other, 'delta'):
+ # Tick offset
+ return other.delta / self
+ return NotImplemented
+
+ elif is_timedelta64_object(other):
+ # convert to Timedelta below
+ pass
+
+ elif hasattr(other, 'dtype'):
  return other / self.to_timedelta64()
 
  elif not _validate_ops_compat(other):
@@ -1160,9 +1192,10 @@ class Timedelta(_Timedelta):
  '{op}'.format(dtype=other.dtype,
  op='__floordiv__'))
 
- if is_float_object(other) and util._checknull(other):
+ elif is_float_object(other) and util._checknull(other):
  # i.e. np.nan
  return NotImplemented
+
  elif not _validate_ops_compat(other):
  return NotImplemented