From 339455bf383a7b8abf2dacec19e4c0c9f30f68f2 Mon Sep 17 00:00:00 2001
From: Lukasz Rzasik <lukasz.rzasik@gmail.com>
Date: Thu, 12 Dec 2024 14:40:18 +0100
Subject: [PATCH] Use saturating_sub consistently

---
 crates/task-impls/src/network.rs             | 11 ++++-------
 crates/task-impls/src/quorum_proposal/mod.rs | 12 ++++++++++--
 2 files changed, 14 insertions(+), 9 deletions(-)

diff --git a/crates/task-impls/src/network.rs b/crates/task-impls/src/network.rs
index 1ca2dc2379..a25bc47962 100644
--- a/crates/task-impls/src/network.rs
+++ b/crates/task-impls/src/network.rs
@@ -361,11 +361,7 @@ impl<
 
     /// Cancel all tasks for previous views
     pub fn cancel_tasks(&mut self, view: TYPES::View) {
-        if *view == 0 {
-            return;
-        }
-        let keep_view = view - 1;
-        let keep = self.transmit_tasks.split_off(&keep_view);
+        let keep = self.transmit_tasks.split_off(&view);
 
         while let Some((_, tasks)) = self.transmit_tasks.pop_first() {
             for task in tasks {
@@ -695,12 +691,13 @@ impl<
                 if epoch > self.epoch {
                     self.epoch = epoch;
                 }
-                self.cancel_tasks(view);
+                let keep_view = TYPES::View::new(view.saturating_sub(1));
+                self.cancel_tasks(keep_view);
                 let net = Arc::clone(&self.network);
                 let epoch = self.epoch.u64();
                 let mem = self.membership.clone();
                 spawn(async move {
-                    net.update_view::<TYPES>(view.saturating_sub(1), epoch, &mem)
+                    net.update_view::<TYPES>(keep_view, epoch, &mem)
                         .await;
                 });
                 None
diff --git a/crates/task-impls/src/quorum_proposal/mod.rs b/crates/task-impls/src/quorum_proposal/mod.rs
index 49875c6480..7cef08bd38 100644
--- a/crates/task-impls/src/quorum_proposal/mod.rs
+++ b/crates/task-impls/src/quorum_proposal/mod.rs
@@ -498,8 +498,16 @@ impl<TYPES: NodeType, I: NodeImplementation<TYPES>, V: Versions>
                     Arc::clone(&event),
                 )?;
             }
-            HotShotEvent::ViewChange(view, _) | HotShotEvent::Timeout(view) => {
-                self.cancel_tasks(*view);
+            HotShotEvent::ViewChange(view, epoch) => {
+                if epoch > &self.cur_epoch {
+                    self.cur_epoch = *epoch;
+                }
+                let keep_view = TYPES::View::new(view.saturating_sub(1));
+                self.cancel_tasks(keep_view);
+            }
+            HotShotEvent::Timeout(view, ..) => {
+                let keep_view = TYPES::View::new(view.saturating_sub(1));
+                self.cancel_tasks(keep_view);
             }
             HotShotEvent::HighQcSend(qc, ..) => {
                 ensure!(qc.view_number() > self.highest_qc.view_number());