From adccce1145d5d82581e4a5da707be35badb2d5a6 Mon Sep 17 00:00:00 2001
From: Alex Auvolat <alex@adnab.me>
Date: Mon, 11 Dec 2023 15:45:14 +0100
Subject: [PATCH] layout: refactor/fix bad while loop

---
 src/rpc/layout/history.rs | 31 ++++++++++++++-----------------
 1 file changed, 14 insertions(+), 17 deletions(-)

diff --git a/src/rpc/layout/history.rs b/src/rpc/layout/history.rs
index 23196aee..b8cc27da 100644
--- a/src/rpc/layout/history.rs
+++ b/src/rpc/layout/history.rs
@@ -86,23 +86,20 @@ impl LayoutHistory {
 		// remove them (keep them in self.old_versions).
 		// ASSUMPTION: we only care about where nodes in the current layout version
 		// are reading from, as we assume older nodes are being discarded.
-		while self.versions.len() > 1 {
-			let current_nodes = &self.current().node_id_vec;
-			let min_version = self.min_stored();
-			let sync_ack_map_min = self
-				.update_trackers
-				.sync_ack_map
-				.min_among(current_nodes, min_version);
-			if self.min_stored() < sync_ack_map_min {
-				let removed = self.versions.remove(0);
-				info!(
-					"Layout history: moving version {} to old_versions",
-					removed.version
-				);
-				self.old_versions.push(removed);
-			} else {
-				break;
-			}
+		let current_nodes = &self.current().node_id_vec;
+		let min_version = self.min_stored();
+		let sync_ack_map_min = self
+			.update_trackers
+			.sync_ack_map
+			.min_among(current_nodes, min_version);
+		while self.min_stored() < sync_ack_map_min {
+			assert!(self.versions.len() > 1);
+			let removed = self.versions.remove(0);
+			info!(
+				"Layout history: moving version {} to old_versions",
+				removed.version
+			);
+			self.old_versions.push(removed);
 		}
 
 		while self.old_versions.len() > OLD_VERSION_COUNT {