message: Feature gate the `ReactorEvent` implementations for `()` behind `cfg(test)`
diff: @@ -224,12 +224,14 @@ pub trait ReactorEvent: Send + Debug + From<ControlAnnouncement> + 'static {
  // Special implementation for the unit type, used in unit tests.
  // TODO: Refactor unit-testing and get rid of this implementation.
  +#[cfg(test)]
  impl ReactorEvent for () {
  fn as_control(&self) -> Option<&ControlAnnouncement> {
  None
  }
  }
  +#[cfg(test)]
  impl From<ControlAnnouncement> for () {
  fn from(_: ControlAnnouncement) -> Self {
  panic!("not supported: `ControlAnnouncement` into `()`")
  