From e594967b47b9f1dedbf8b9693b61a38f2994aa69 Mon Sep 17 00:00:00 2001
From: Josh Stone <cuviper@gmail.com>
Date: Fri, 30 Jul 2021 16:25:23 -0700
Subject: [PATCH] impl Debug for ParValuesMut

---
 src/map.rs       | 2 ++
 src/rayon/map.rs | 7 +++++++
 2 files changed, 9 insertions(+)

diff --git a/src/map.rs b/src/map.rs
index 4beb5f44..3a43a79b 100644
--- a/src/map.rs
+++ b/src/map.rs
@@ -948,6 +948,8 @@ impl<K, V> ExactSizeIterator for ValuesMut<'_, K, V> {
 
 impl<K, V> FusedIterator for ValuesMut<'_, K, V> {}
 
+// TODO: `impl Debug for ValuesMut` once we have MSRV 1.53 for `slice::IterMut::as_slice`
+
 /// An owning iterator over the values of a `IndexMap`.
 ///
 /// This `struct` is created by the [`into_values`] method on [`IndexMap`].
diff --git a/src/rayon/map.rs b/src/rayon/map.rs
index 1bfce60c..bedad3c4 100644
--- a/src/rayon/map.rs
+++ b/src/rayon/map.rs
@@ -346,6 +346,13 @@ pub struct ParValuesMut<'a, K, V> {
     entries: &'a mut [Bucket<K, V>],
 }
 
+impl<K, V: fmt::Debug> fmt::Debug for ParValuesMut<'_, K, V> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let iter = self.entries.iter().map(Bucket::value_ref);
+        f.debug_list().entries(iter).finish()
+    }
+}
+
 impl<'a, K: Send, V: Send> ParallelIterator for ParValuesMut<'a, K, V> {
     type Item = &'a mut V;