From 468a90e5ffe9e8cf837ef0c7df63d61171b18823 Mon Sep 17 00:00:00 2001
From: Eliza Weisman <eliza@buoyant.io>
Date: Thu, 8 Sep 2022 11:23:52 -0700
Subject: [PATCH] feat(cordyceps): add `FusedIterator` impls for `List`
 iterators

This enables additional optimizations if these iterators are guaranteed
to never return `Some` again after returning `None` once, which they
are.
---
 cordyceps/src/list.rs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/cordyceps/src/list.rs b/cordyceps/src/list.rs
index ad2c4da9..e2d56e79 100644
--- a/cordyceps/src/list.rs
+++ b/cordyceps/src/list.rs
@@ -1247,6 +1247,8 @@ impl<'list, T: Linked<Links<T>> + ?Sized> DoubleEndedIterator for Iter<'list, T>
     }
 }
 
+impl<'list, T: Linked<Links<T>> + ?Sized> iter::FusedIterator for Iter<'list, T> {}
+
 // === impl IterMut ====
 
 impl<'list, T: Linked<Links<T>> + ?Sized> Iterator for IterMut<'list, T> {
@@ -1314,6 +1316,8 @@ impl<'list, T: Linked<Links<T>> + ?Sized> DoubleEndedIterator for IterMut<'list,
     }
 }
 
+impl<'list, T: Linked<Links<T>> + ?Sized> iter::FusedIterator for IterMut<'list, T> {}
+
 // === impl IntoIter ===
 
 impl<T: Linked<Links<T>> + ?Sized> fmt::Debug for IntoIter<T> {
@@ -1350,6 +1354,8 @@ impl<T: Linked<Links<T>> + ?Sized> ExactSizeIterator for IntoIter<T> {
     }
 }
 
+impl<T: Linked<Links<T>> + ?Sized> iter::FusedIterator for IntoIter<T> {}
+
 // === impl DrainFilter ===
 
 impl<T, F> Iterator for DrainFilter<'_, T, F>