From 4ed90f4214a73bdb620936c19213a2902dfd2bb9 Mon Sep 17 00:00:00 2001
From: Kaede Hoshikawa <futursolo@icloud.com>
Date: Sun, 8 Jan 2023 22:41:43 +0900
Subject: [PATCH] Prefer pop_first if it is available.

---
 packages/yew/src/scheduler.rs | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/packages/yew/src/scheduler.rs b/packages/yew/src/scheduler.rs
index c7f37dbca09..6f9113bf346 100644
--- a/packages/yew/src/scheduler.rs
+++ b/packages/yew/src/scheduler.rs
@@ -46,12 +46,20 @@ impl TopologicalQueue {
     }
 
     /// Take a single entry, preferring parents over children
+    #[rustversion::before(1.66)]
     fn pop_topmost(&mut self) -> Option<QueueEntry> {
-        // To be replaced with BTreeMap::pop_first once it is stable.
+        // BTreeMap::pop_first is available after 1.66.
         let key = *self.inner.keys().next()?;
         self.inner.remove(&key)
     }
 
+    /// Take a single entry, preferring parents over children
+    #[rustversion::since(1.66)]
+    #[inline]
+    fn pop_topmost(&mut self) -> Option<QueueEntry> {
+        self.inner.pop_first().map(|(_, v)| v)
+    }
+
     /// Drain all entries, such that children are queued before parents
     fn drain_post_order_into(&mut self, queue: &mut Vec<QueueEntry>) {
         if self.inner.is_empty() {