DEPR: Timedelta.__rfloordiv__(int_dtype) (pandas-dev#29797)

Author: jbrockmendel

doc/source/whatsnew/v1.0.0.rst

@@ -401,6 +401,7 @@ or ``matplotlib.Axes.plot``. See :ref:`plotting.formatters` for more.
 
 **Other removals**
 
+- Floordiv of integer-dtyped array by :class:`Timedelta` now raises ``TypeError`` (:issue:`21036`)
 - Removed the previously deprecated :meth:`Index.summary` (:issue:`18217`)
 - Removed the previously deprecated :meth:`Series.get_value`, :meth:`Series.set_value`, :meth:`DataFrame.get_value`, :meth:`DataFrame.set_value` (:issue:`17739`)
 - Changed the the default value of `inplace` in :meth:`DataFrame.set_index` and :meth:`Series.set_axis`. It now defaults to False (:issue:`27600`)

pandas/_libs/tslibs/timedeltas.pyx

@@ -1509,18 +1509,8 @@ class Timedelta(_Timedelta):
             if other.dtype.kind == 'm':
                 # also timedelta-like
                 return _broadcast_floordiv_td64(self.value, other, _rfloordiv)
-            elif other.dtype.kind == 'i':
-                # Backwards compatibility
-                # GH-19761
-                msg = textwrap.dedent("""\
-                Floor division between integer array and Timedelta is
-                deprecated. Use 'array // timedelta.value' instead.
-                If you want to obtain epochs from an array of timestamps,
-                you can rather use
-                '(array - pd.Timestamp("1970-01-01")) // pd.Timedelta("1s")'.
-                """)
-                warnings.warn(msg, FutureWarning)
-                return other // self.value
+
+            # Includes integer array // Timedelta, deprecated in GH#19761
             raise TypeError(f'Invalid dtype {other.dtype} for __floordiv__')
 
         elif is_float_object(other) and util.is_nan(other):

pandas/tests/scalar/timedelta/test_arithmetic.py

@@ -463,8 +463,8 @@ def test_td_rfloordiv_numeric_scalar(self):
             td.__rfloordiv__(np.float64(2.0))
         with pytest.raises(TypeError):
             td.__rfloordiv__(np.uint8(9))
-        with tm.assert_produces_warning(FutureWarning):
-            # GH-19761: Change to TypeError.
+        with pytest.raises(TypeError, match="Invalid dtype"):
+            # deprecated GH#19761, enforced GH#29797
             td.__rfloordiv__(np.int32(2.0))
 
     def test_td_rfloordiv_timedeltalike_array(self):
@@ -490,7 +490,9 @@ def test_td_rfloordiv_numeric_series(self):
         ser = pd.Series([1], dtype=np.int64)
         res = td.__rfloordiv__(ser)
         assert res is NotImplemented
-        with tm.assert_produces_warning(FutureWarning, check_stacklevel=False):
+
+        with pytest.raises(TypeError, match="Invalid dtype"):
+            # Deprecated GH#19761, enforced GH#29797
             # TODO: GH-19761. Change to TypeError.
             ser // td
 

pandas/tests/scalar/timedelta/test_timedelta.py

@@ -21,17 +21,11 @@ def test_arithmetic_overflow(self):
             Timestamp("1700-01-01") + timedelta(days=13 * 19999)
 
     def test_array_timedelta_floordiv(self):
-        # https://github.com/pandas-dev/pandas/issues/19761
+        # deprected GH#19761, enforced GH#29797
         ints = pd.date_range("2012-10-08", periods=4, freq="D").view("i8")
-        msg = r"Use 'array // timedelta.value'"
-        with tm.assert_produces_warning(FutureWarning) as m:
-            result = ints // Timedelta(1, unit="s")
 
-        assert msg in str(m[0].message)
-        expected = np.array(
-            [1349654400, 1349740800, 1349827200, 1349913600], dtype="i8"
-        )
-        tm.assert_numpy_array_equal(result, expected)
+        with pytest.raises(TypeError, match="Invalid dtype"):
+            ints // Timedelta(1, unit="s")
 
     def test_ops_error_str(self):
         # GH 13624