chore: checkpoint before Python removal

vendor/dyn-clone/tests/trait.rs

@@ -0,0 +1,64 @@
+#![cfg(target_has_atomic = "ptr")]
+
+use dyn_clone::DynClone;
+use std::fmt::{self, Display};
+use std::sync::{Arc, Mutex};
+
+struct Log {
+    id: u64,
+    events: Arc<Mutex<Vec<String>>>,
+}
+
+impl Clone for Log {
+    fn clone(&self) -> Self {
+        Log {
+            id: self.id + 1,
+            events: self.events.clone(),
+        }
+    }
+}
+
+impl Display for Log {
+    fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+        write!(formatter, "id={}", self.id)
+    }
+}
+
+impl Drop for Log {
+    fn drop(&mut self) {
+        self.events.lock().unwrap().push(format!("dropping {self}"));
+    }
+}
+
+#[test]
+fn clone_sized() {
+    let arc = Arc::new(0);
+    assert_eq!(Arc::strong_count(&arc), 1);
+
+    let c = dyn_clone::clone(&arc);
+    assert_eq!(Arc::strong_count(&arc), 2);
+    drop(c);
+    assert_eq!(Arc::strong_count(&arc), 1);
+}
+
+#[test]
+fn clone_trait_object() {
+    trait MyTrait: Display + Sync + DynClone {}
+
+    impl MyTrait for Log {}
+
+    let events = Arc::new(Mutex::new(Vec::new()));
+    let mut expected = Vec::new();
+    {
+        let b11: Box<dyn MyTrait> = Box::new(Log {
+            id: 11,
+            events: events.clone(),
+        });
+        let b12 = dyn_clone::clone_box(&*b11);
+        assert_eq!(b11.to_string(), "id=11");
+        assert_eq!(b12.to_string(), "id=12");
+        expected.push("dropping id=12".to_owned());
+        expected.push("dropping id=11".to_owned());
+    }
+    assert_eq!(*events.lock().unwrap(), expected);
+}