From 3e6db95e308593fac0b9f132454db44295a94b08 Mon Sep 17 00:00:00 2001
From: Guillaume Gomez <guillaume1.gomez@gmail.com>
Date: Fri, 6 Oct 2023 11:24:35 +0200
Subject: [PATCH] Add regression test for #11561

---
 tests/ui/needless_pass_by_ref_mut.rs | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/tests/ui/needless_pass_by_ref_mut.rs b/tests/ui/needless_pass_by_ref_mut.rs
index 95fe1385c06..ea5e74c4c00 100644
--- a/tests/ui/needless_pass_by_ref_mut.rs
+++ b/tests/ui/needless_pass_by_ref_mut.rs
@@ -297,6 +297,11 @@ fn true_setter(b: &mut bool) -> impl FnOnce() + '_ {
     move || set_true(b)
 }
 
+// Should not warn.
+fn filter_copy<T: Copy>(predicate: &mut impl FnMut(T) -> bool) -> impl FnMut(&T) -> bool + '_ {
+    move |&item| predicate(item)
+}
+
 fn main() {
     let mut u = 0;
     let mut v = vec![0];