Support reflected timedelta addition for Time

docs/docs/addition_subtraction.md

@@ -85,3 +85,16 @@ Each method returns a new `DateTime` instance.
 
     Passing negative values to `add()` is also possible and will act exactly
     like `subtract()`
+
+## Time arithmetic
+
+`Time` instances support adding a `datetime.timedelta` on either side of `+`.
+As with `Time.add_timedelta()`, the duration must not have a nonzero `days` component.
+
+```python
+>>> from datetime import timedelta
+>>> pendulum.time(12, 30) + timedelta(minutes=15)
+Time(12, 45, 0)
+>>> timedelta(minutes=15) + pendulum.time(12, 30)
+Time(12, 45, 0)
+```

src/pendulum/time.py

@@ -167,6 +167,9 @@ def __add__(self, other: datetime.timedelta) -> Time:
 
         return self.add_timedelta(other)
 
+    def __radd__(self, other: datetime.timedelta) -> Time:
+        return self.__add__(other)
+
     @overload
     def __sub__(self, other: time) -> pendulum.Duration: ...
 

tests/time/test_add.py

@@ -68,6 +68,56 @@ def test_add_timedelta_with_days():
         d.add_timedelta(delta)
 
 
+@pytest.mark.parametrize("duration_type", [timedelta, pendulum.duration])
+@pytest.mark.parametrize(
+    "time_args, duration_args, expected_args",
+    [
+        (
+            (3, 12, 15, 654321),
+            {"seconds": 45, "microseconds": 123456},
+            (3, 13, 0, 777777),
+        ),
+        ((12, 0), {}, (12, 0)),
+        ((23, 59, 59, 999999), {"microseconds": 1}, (0, 0)),
+        ((12, 0), {"hours": 23}, (11, 0)),
+    ],
+)
+def test_reflected_addition(duration_type, time_args, duration_args, expected_args):
+    value = pendulum.time(*time_args)
+    delta = duration_type(**duration_args)
+    expected = pendulum.time(*expected_args)
+
+    assert value + delta == expected
+    result = delta + value
+    assert result == expected
+    assert isinstance(result, pendulum.Time)
+
+
+@pytest.mark.parametrize("days", [-1, 1])
+def test_reflected_addition_rejects_days(days):
+    value = pendulum.time(12, 0)
+    delta = timedelta(days=days)
+
+    with pytest.raises(TypeError):
+        value + delta
+    with pytest.raises(TypeError):
+        delta + value
+
+
+def test_reflected_addition_delegates_to_subclass():
+    calls = []
+    expected = pendulum.time(6, 0)
+
+    class CustomTime(pendulum.Time):
+        def __add__(self, other):
+            calls.append(other)
+            return expected
+
+    delta = timedelta(minutes=5)
+    assert delta + CustomTime(12, 0) is expected
+    assert calls == [delta]
+
+
 def test_addition_invalid_type():
     d = pendulum.time(3, 12, 15, 654321)