Auto merge of #65495 - Centril:rollup-tguwjt5, r=Centril

Rollup of 8 pull requests

Successful merges:

 - #65237 (Move debug_map assertions after check for err)
 - #65316 (make File::try_clone produce non-inheritable handles on Windows)
 - #65319 (InterpCx: make memory field public)
 - #65461 (Don't recommend ONCE_INIT in std::sync::Once)
 - #65465 (Move syntax::ext to a syntax_expand and refactor some attribute logic)
 - #65475 (add example for type_name)
 - #65478 (fmt::Write is about string slices, not byte slices)
 - #65486 (doc: fix typo in OsStrExt and OsStringExt)

Failed merges:

r? @ghost

1 files changed, 40 insertions, 0 deletions

diff --git a/src/libcore/tests/fmt/builders.rs b/src/libcore/tests/fmt/builders.rs
index 200659b91bb..25572443281 100644
--- a/src/libcore/tests/fmt/builders.rs
+++ b/src/libcore/tests/fmt/builders.rs
@@ -320,6 +320,46 @@ mod debug_map {
     }
 
     #[test]
+    fn test_entry_err() {
+        // Ensure errors in a map entry don't trigger panics (#65231)
+        use std::fmt::Write;
+
+        struct ErrorFmt;
+
+        impl fmt::Debug for ErrorFmt {
+            fn fmt(&self, _: &mut fmt::Formatter<'_>) -> fmt::Result {
+                Err(fmt::Error)
+            }
+        }
+
+        struct KeyValue<K, V>(usize, K, V);
+
+        impl<K, V> fmt::Debug for KeyValue<K, V>
+        where
+            K: fmt::Debug,
+            V: fmt::Debug,
+        {
+            fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
+                let mut map = fmt.debug_map();
+
+                for _ in 0..self.0 {
+                    map.entry(&self.1, &self.2);
+                }
+
+                map.finish()
+            }
+        }
+
+        let mut buf = String::new();
+
+        assert!(write!(&mut buf, "{:?}", KeyValue(1, ErrorFmt, "bar")).is_err());
+        assert!(write!(&mut buf, "{:?}", KeyValue(1, "foo", ErrorFmt)).is_err());
+
+        assert!(write!(&mut buf, "{:?}", KeyValue(2, ErrorFmt, "bar")).is_err());
+        assert!(write!(&mut buf, "{:?}", KeyValue(2, "foo", ErrorFmt)).is_err());
+    }
+
+    #[test]
     #[should_panic]
     fn test_invalid_key_when_entry_is_incomplete() {
         struct Foo;