From 543c30c9366a823bd20938ead83dbf77b445a023 Mon Sep 17 00:00:00 2001
From: Philippe-Cholet <phcholet@orange.fr>
Date: Thu, 18 Jan 2024 11:53:06 +0100
Subject: [PATCH] `RepeatN`: implement `PeekingNext`

---
 src/peeking_take_while.rs | 14 ++++++++++++++
 src/repeatn.rs            |  2 +-
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/src/peeking_take_while.rs b/src/peeking_take_while.rs
index b4852c1c9..b224907aa 100644
--- a/src/peeking_take_while.rs
+++ b/src/peeking_take_while.rs
@@ -1,6 +1,7 @@
 use crate::PutBack;
 #[cfg(feature = "use_alloc")]
 use crate::PutBackN;
+use crate::RepeatN;
 use std::iter::Peekable;
 
 /// An iterator that allows peeking at an element before deciding to accept it.
@@ -91,6 +92,19 @@ where
     }
 }
 
+impl<T: Clone> PeekingNext for RepeatN<T> {
+    fn peeking_next<F>(&mut self, accept: F) -> Option<Self::Item>
+    where
+        F: FnOnce(&Self::Item) -> bool,
+    {
+        let r = self.elt.as_ref()?;
+        if !accept(r) {
+            return None;
+        }
+        self.next()
+    }
+}
+
 /// An iterator adaptor that takes items while a closure returns `true`.
 ///
 /// See [`.peeking_take_while()`](crate::Itertools::peeking_take_while)
diff --git a/src/repeatn.rs b/src/repeatn.rs
index 539c42615..d86ad9fac 100644
--- a/src/repeatn.rs
+++ b/src/repeatn.rs
@@ -6,7 +6,7 @@ use std::iter::FusedIterator;
 #[must_use = "iterators are lazy and do nothing unless consumed"]
 #[derive(Clone, Debug)]
 pub struct RepeatN<A> {
-    elt: Option<A>,
+    pub(crate) elt: Option<A>,
     n: usize,
 }