add nullify test

Author: patrick-ogrady

consensus/src/threshold_simplex/actors/voter/actor.rs

@@ -213,7 +213,15 @@ impl<
         // Check if already issued finalize
         let Some(finalize) = &self.finalizes[public_key_index as usize] else {
             // Store the nullify
-            return self.nullifies.insert(public_key_index, nullify).is_none();
+            let entry = self.nullifies.entry(public_key_index);
+            return match entry {
+                std::collections::hash_map::Entry::Occupied(_) => false,
+                std::collections::hash_map::Entry::Vacant(_) => {
+                    entry.or_insert(nullify.clone());
+                    self.reporter.report(Activity::Nullify(nullify)).await;
+                    true
+                }
+            };
         };
 
         // Create fault

consensus/src/threshold_simplex/mod.rs

@@ -1085,6 +1085,9 @@ mod tests {
                 {
                     let nullifies = supervisor.nullifies.lock().unwrap();
                     for view in offline_views.iter() {
+                        if *view == 0 {
+                            continue;
+                        }
                         let nullifies = nullifies.get(view).unwrap();
                         if nullifies.len() < threshold as usize {
                             panic!("view: {}", view);