fix lint issues

Author: Brindrajsinh-Chauhan

crates/malachite-app/src/handlers/started_round.rs

@@ -99,13 +99,15 @@ async fn on_started_round(
 
     if round.as_i64() > 0 {
         let current_round = round.as_u32().expect("round is defined");
-        let missed_round = Round::new(current_round - 1);
+        let missed_round = Round::new(current_round.saturating_sub(1));
         let missed_proposer = state
             .ctx
             .proposer_selector
             .select_proposer(state.validator_set(), height, missed_round)
             .address;
-        state.metrics().inc_consensus_round_missed(missed_proposer, height, missed_round);
+        state
+            .metrics()
+            .inc_consensus_round_missed(missed_proposer, height, missed_round);
     }
 
     state.current_round = round;

crates/malachite-app/src/metrics/app.rs

@@ -488,7 +488,12 @@ impl AppMetrics {
 
     /// Total number of missed consensus rounds since start.
     #[cfg(test)]
-    pub fn get_consensus_round_missed_count(&self, proposer: Address, height: Height, round: Round) -> u64 {
+    pub fn get_consensus_round_missed_count(
+        &self,
+        proposer: Address,
+        height: Height,
+        round: Round,
+    ) -> u64 {
         self.consensus_round_missed
             .get_or_create(&RoundMissedLabel::new(proposer, height, round))
             .get()
@@ -705,8 +710,17 @@ mod tests {
         metrics.inc_consensus_round_missed(proposer, Height::new(2), Round::new(0));
         metrics.inc_consensus_round_missed(proposer, Height::new(2), Round::new(1));
 
-        assert_eq!(metrics.get_consensus_round_missed_count(proposer, Height::new(1), Round::new(0)), 1);
-        assert_eq!(metrics.get_consensus_round_missed_count(proposer, Height::new(2), Round::new(0)), 1);
-        assert_eq!(metrics.get_consensus_round_missed_count(proposer, Height::new(2), Round::new(1)), 1);
+        assert_eq!(
+            metrics.get_consensus_round_missed_count(proposer, Height::new(1), Round::new(0)),
+            1
+        );
+        assert_eq!(
+            metrics.get_consensus_round_missed_count(proposer, Height::new(2), Round::new(0)),
+            1
+        );
+        assert_eq!(
+            metrics.get_consensus_round_missed_count(proposer, Height::new(2), Round::new(1)),
+            1
+        );
     }
 }