randomPeer: Return if the context is cancelled when waiting for peers. (#15876)

* `randomPeer`: Return if the context is cancelled when waiting for peers.

* `randomPeer`: Refactor to reduce indentation.

beacon-chain/sync/data_column_sidecars.go

@@ -1122,19 +1122,21 @@ func randomPeer(
 			}
 		}
 
-		slices.Sort(nonRateLimitedPeers)
-
-		if len(nonRateLimitedPeers) == 0 {
-			log.WithFields(logrus.Fields{
-				"peerCount": peerCount,
-				"delay":     waitPeriod,
-			}).Debug("Waiting for a peer with enough bandwidth for data column sidecars")
-			time.Sleep(waitPeriod)
-			continue
+		if len(nonRateLimitedPeers) > 0 {
+			slices.Sort(nonRateLimitedPeers)
+			randomIndex := randomSource.Intn(len(nonRateLimitedPeers))
+			return nonRateLimitedPeers[randomIndex], nil
 		}
 
-		randomIndex := randomSource.Intn(len(nonRateLimitedPeers))
-		return nonRateLimitedPeers[randomIndex], nil
+		log.WithFields(logrus.Fields{
+			"peerCount": peerCount,
+			"delay":     waitPeriod,
+		}).Debug("Waiting for a peer with enough bandwidth for data column sidecars")
+
+		select {
+		case <-time.After(waitPeriod):
+		case <-ctx.Done():
+		}
 	}
 
 	return "", ctx.Err()

changelog/manu-random-peer.md

@@ -0,0 +1,2 @@
+### Fixed 
+- `randomPeer`: Return if the context is cancelled when waiting for peers.