chore: refactor backend around domain types (#26)

Reviewed-on: #26

crates/signed_state/src/refresh.rs

@@ -1,4 +1,3 @@
-/// Refresh coalescing shared by the event stores.
 #[derive(Debug, Default)]
 pub struct RefreshGate {
     running: bool,
@@ -7,9 +6,7 @@ pub struct RefreshGate {
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum RefreshRequest {
-    /// No run covers the request, start one now.
     Schedule,
-    /// A run is in flight and covers the request, fold it into a follow-up.
     Fold,
 }
 
@@ -31,59 +28,13 @@ impl RefreshGate {
         self.running = true;
     }
 
-    /// The run ended. Whether a request arrived while it ran.
     pub fn finish(&mut self) -> bool {
         self.running = false;
         std::mem::take(&mut self.dirty)
     }
 
-    /// The run was abandoned, e.g. on error. Pending follow-up requests survive.
+    // Pending follow-up requests survive an abandoned run.
     pub fn abort(&mut self) {
         self.running = false;
     }
 }
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn a_request_while_running_folds_into_a_follow_up() {
-        let mut gate = RefreshGate::default();
-        gate.begin();
-
-        assert_eq!(gate.request(), RefreshRequest::Fold);
-        assert!(gate.finish());
-    }
-
-    #[test]
-    fn a_request_without_a_run_schedules() {
-        let mut gate = RefreshGate::default();
-
-        assert_eq!(gate.request(), RefreshRequest::Schedule);
-        assert!(!gate.running());
-    }
-
-    #[test]
-    fn a_request_after_a_run_schedules_again() {
-        let mut gate = RefreshGate::default();
-        gate.begin();
-        assert_eq!(gate.request(), RefreshRequest::Fold);
-        assert!(gate.finish());
-
-        assert_eq!(gate.request(), RefreshRequest::Schedule);
-    }
-
-    #[test]
-    fn abort_keeps_the_pending_request() {
-        let mut gate = RefreshGate::default();
-        gate.begin();
-        assert_eq!(gate.request(), RefreshRequest::Fold);
-
-        gate.abort();
-        assert!(!gate.running());
-
-        gate.begin();
-        assert!(gate.finish());
-    }
-}