From e6a874b0bf35b7f5fadfc63f18be45ecc30579e7 Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Tue, 29 Aug 2017 16:51:26 +0200
Subject: [PATCH] test new From instances for Rc

---
 tests/run-pass/rc.rs | 20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/tests/run-pass/rc.rs b/tests/run-pass/rc.rs
index c6de3675abe8..0bf707503112 100644
--- a/tests/run-pass/rc.rs
+++ b/tests/run-pass/rc.rs
@@ -1,11 +1,11 @@
 use std::cell::RefCell;
 use std::rc::Rc;
 
-fn rc_refcell() -> i32 {
+fn rc_refcell() {
     let r = Rc::new(RefCell::new(42));
     *r.borrow_mut() += 10;
     let x = *r.borrow();
-    x
+    assert_eq!(x, 52);
 }
 
 fn rc_raw() {
@@ -17,7 +17,23 @@ fn rc_raw() {
     assert!(Rc::try_unwrap(r2).is_ok());
 }
 
+// Make sure this Rc doesn't fall apart when touched
+fn check_unique_rc<T: ?Sized>(mut r: Rc<T>) {
+    let r2 = r.clone();
+    assert!(Rc::get_mut(&mut r).is_none());
+    drop(r2);
+    assert!(Rc::get_mut(&mut r).is_some());
+}
+
+fn rc_from() {
+    check_unique_rc::<[_]>(Rc::from(&[1,2,3] as &[_]));
+    check_unique_rc::<[_]>(Rc::from(vec![1,2,3]));
+    check_unique_rc::<[_]>(Rc::from(Box::new([1,2,3]) as Box<[_]>));
+    check_unique_rc::<str>(Rc::from("Hello, World!"));
+}
+
 fn main() {
     rc_refcell();
     rc_raw();
+    rc_from();
 }