add arbiter handle assoc fn (#274)

* add arbiter handle assoc fn

actix-rt/CHANGES.md

@@ -1,6 +1,9 @@
 # Changes
 
 ## Unreleased - 2021-xx-xx
+* Add `Arbiter::handle` to get a handle of an owned Arbiter. [#274]
+
+[#274]: https://github.com/actix/actix-net/pull/274
 
 
 ## 2.0.1 - 2021-02-06

actix-rt/src/arbiter.rs

@@ -172,13 +172,18 @@ impl Arbiter {
         hnd
     }
 
+    /// Return a handle to the this Arbiter's message sender.
+    pub fn handle(&self) -> ArbiterHandle {
+        ArbiterHandle::new(self.tx.clone())
+    }
+
     /// Return a handle to the current thread's Arbiter's message sender.
     ///
     /// # Panics
     /// Panics if no Arbiter is running on the current thread.
     pub fn current() -> ArbiterHandle {
         HANDLE.with(|cell| match *cell.borrow() {
-            Some(ref addr) => addr.clone(),
+            Some(ref hnd) => hnd.clone(),
             None => panic!("Arbiter is not running."),
         })
     }

actix-rt/tests/tests.rs

@@ -122,6 +122,28 @@ fn arbiter_spawn_fn_runs() {
     arbiter.join().unwrap();
 }
 
+#[test]
+fn arbiter_handle_spawn_fn_runs() {
+    let sys = System::new();
+
+    let (tx, rx) = channel::<u32>();
+
+    let arbiter = Arbiter::new();
+    let handle = arbiter.handle();
+    drop(arbiter);
+
+    handle.spawn_fn(move || {
+        tx.send(42).unwrap();
+        System::current().stop()
+    });
+
+    let num = rx.recv_timeout(Duration::from_secs(2)).unwrap();
+    assert_eq!(num, 42);
+
+    handle.stop();
+    sys.run().unwrap();
+}
+
 #[test]
 fn arbiter_drop_no_panic_fn() {
     let _ = System::new();