From b2ee932377dbead25f64708655e525c90f41a107 Mon Sep 17 00:00:00 2001
From: David Tolnay <dtolnay@gmail.com>
Date: Sun, 19 May 2024 11:29:14 -0700
Subject: [PATCH] Make FoldHelper friendlier to debug mode

---
 src/gen_helper.rs | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/gen_helper.rs b/src/gen_helper.rs
index 2ff445b1b3..e24f74fb2e 100644
--- a/src/gen_helper.rs
+++ b/src/gen_helper.rs
@@ -26,8 +26,10 @@ pub(crate) mod fold {
             F: FnMut(Self::Item) -> Self::Item,
         {
             self.into_pairs()
-                .map(Pair::into_tuple)
-                .map(|(t, p)| Pair::new(f(t), p))
+                .map(|pair| match pair {
+                    Pair::Punctuated(t, p) => Pair::Punctuated(f(t), p),
+                    Pair::End(t) => Pair::End(f(t)),
+                })
                 .collect()
         }
     }