[consensus/ordered-broadcast] Add External Sequencer Test + Improve Coverage on Sequencer Checks + Emit Tip Even if Sequencer (#834)

Author: patrick-ogrady

consensus/src/ordered_broadcast/engine.rs

@@ -488,7 +488,15 @@ impl<
             return Err(Error::AppVerifiedPayloadMismatch);
         }
 
-        // Construct partial signature
+        // Emit the activity
+        self.reporter
+            .report(Activity::Tip(Proposal::new(
+                tip.chunk.clone(),
+                tip.signature.clone(),
+            )))
+            .await;
+
+        // Construct partial signature (if a validator)
         let Some(share) = self.validators.share(self.epoch) else {
             return Err(Error::UnknownShare(self.epoch));
         };
@@ -524,14 +532,6 @@ impl<
             .await
             .map_err(|_| Error::UnableToSendMessage)?;
 
-        // Emit the activity
-        self.reporter
-            .report(Activity::Proposal(Proposal::new(
-                tip.chunk,
-                tip.signature.clone(),
-            )))
-            .await;
-
         Ok(())
     }
 

consensus/src/ordered_broadcast/mocks/reporter.rs

@@ -175,7 +175,7 @@ impl<C: Verifier, D: Digest> Z for Mailbox<C, D> {
 
     async fn report(&mut self, activity: Self::Activity) {
         match activity {
-            Activity::Proposal(proposal) => {
+            Activity::Tip(proposal) => {
                 self.sender
                     .send(Message::Proposal(proposal))
                     .await

consensus/src/ordered_broadcast/mocks/validators.rs

@@ -11,11 +11,11 @@ pub struct Validators<P: Array> {
     identity: Poly<Public>,
     validators: Vec<P>,
     validators_map: HashMap<P, u32>,
-    share: Share,
+    share: Option<Share>,
 }
 
 impl<P: Array> Validators<P> {
-    pub fn new(identity: Poly<Public>, mut validators: Vec<P>, share: Share) -> Self {
+    pub fn new(identity: Poly<Public>, mut validators: Vec<P>, share: Option<Share>) -> Self {
         // Setup validators
         validators.sort();
         let mut validators_map = HashMap::new();
@@ -63,6 +63,6 @@ impl<P: Array> ThresholdSupervisor for Validators<P> {
     }
 
     fn share(&self, _: Self::Index) -> Option<&Self::Share> {
-        Some(&self.share)
+        self.share.as_ref()
     }
 }