Do not require T: Clone for EventLoopProxy<T>: Clone (#1086)

* Do not require `T: Clone` for `EventLoopProxy<T>: Clone`

* Update `CHANGELOG.md`

* Remove the conflicting `Clone` impl

* Fix match statement

CHANGELOG.md

@@ -15,6 +15,7 @@
 - On iOS, add support for deferring system gestures.
 - On iOS, fix a crash that occurred while acquiring a monitor's name.
 - On iOS, fix armv7-apple-ios compile target.
+- Removed the `T: Clone` requirement from the `Clone` impl of `EventLoopProxy<T>`.
 
 # 0.20.0 Alpha 2 (2019-07-09)
 

src/event_loop.rs

@@ -173,11 +173,18 @@ impl<T> Deref for EventLoop<T> {
 }
 
 /// Used to send custom events to `EventLoop`.
-#[derive(Clone)]
 pub struct EventLoopProxy<T: 'static> {
     event_loop_proxy: platform_impl::EventLoopProxy<T>,
 }
 
+impl<T: 'static> Clone for EventLoopProxy<T> {
+    fn clone(&self) -> Self {
+        Self {
+            event_loop_proxy: self.event_loop_proxy.clone(),
+        }
+    }
+}
+
 impl<T: 'static> EventLoopProxy<T> {
     /// Send an event to the `EventLoop` from which this proxy was created. This emits a
     /// `UserEvent(event)` event in the event loop, where `event` is the value passed to this

src/platform_impl/linux/mod.rs

@@ -479,12 +479,20 @@ pub enum EventLoop<T: 'static> {
     X(x11::EventLoop<T>),
 }
 
-#[derive(Clone)]
 pub enum EventLoopProxy<T: 'static> {
     X(x11::EventLoopProxy<T>),
     Wayland(wayland::EventLoopProxy<T>),
 }
 
+impl<T: 'static> Clone for EventLoopProxy<T> {
+    fn clone(&self) -> Self {
+        match self {
+            EventLoopProxy::X(proxy) => EventLoopProxy::X(proxy.clone()),
+            EventLoopProxy::Wayland(proxy) => EventLoopProxy::Wayland(proxy.clone()),
+        }
+    }
+}
+
 impl<T: 'static> EventLoop<T> {
     pub fn new() -> EventLoop<T> {
         if let Ok(env_var) = env::var(BACKEND_PREFERENCE_ENV_VAR) {

src/platform_impl/linux/wayland/event_loop.rs

@@ -90,7 +90,6 @@ pub struct EventLoop<T: 'static> {
 // A handle that can be sent across threads and used to wake up the `EventLoop`.
 //
 // We should only try and wake up the `EventLoop` if it still exists, so we hold Weak ptrs.
-#[derive(Clone)]
 pub struct EventLoopProxy<T: 'static> {
     user_sender: ::calloop::channel::Sender<T>,
 }
@@ -111,6 +110,14 @@ pub struct EventLoopWindowTarget<T> {
     _marker: ::std::marker::PhantomData<T>,
 }
 
+impl<T: 'static> Clone for EventLoopProxy<T> {
+    fn clone(&self) -> Self {
+        EventLoopProxy {
+            user_sender: self.user_sender.clone(),
+        }
+    }
+}
+
 impl<T: 'static> EventLoopProxy<T> {
     pub fn send_event(&self, event: T) -> Result<(), EventLoopClosed> {
         self.user_sender.send(event).map_err(|_| EventLoopClosed)

src/platform_impl/linux/x11/mod.rs

@@ -66,11 +66,18 @@ pub struct EventLoop<T: 'static> {
     target: Rc<RootELW<T>>,
 }
 
-#[derive(Clone)]
 pub struct EventLoopProxy<T: 'static> {
     user_sender: ::calloop::channel::Sender<T>,
 }
 
+impl<T: 'static> Clone for EventLoopProxy<T> {
+    fn clone(&self) -> Self {
+        EventLoopProxy {
+            user_sender: self.user_sender.clone(),
+        }
+    }
+}
+
 impl<T: 'static> EventLoop<T> {
     pub fn new(xconn: Arc<XConnection>) -> EventLoop<T> {
         let root = unsafe { (xconn.xlib.XDefaultRootWindow)(xconn.display) };

src/platform_impl/macos/event_loop.rs

@@ -108,7 +108,6 @@ impl<T> EventLoop<T> {
     }
 }
 
-#[derive(Clone)]
 pub struct Proxy<T> {
     sender: mpsc::Sender<T>,
     source: CFRunLoopSourceRef,
@@ -117,6 +116,12 @@ pub struct Proxy<T> {
 unsafe impl<T> Send for Proxy<T> {}
 unsafe impl<T> Sync for Proxy<T> {}
 
+impl<T> Clone for Proxy<T> {
+    fn clone(&self) -> Self {
+        Proxy::new(self.sender.clone())
+    }
+}
+
 impl<T> Proxy<T> {
     fn new(sender: mpsc::Sender<T>) -> Self {
         unsafe {

src/platform_impl/windows/event_loop.rs

@@ -678,13 +678,21 @@ impl EventLoopThreadExecutor {
 
 type ThreadExecFn = Box<Box<dyn FnMut()>>;
 
-#[derive(Clone)]
 pub struct EventLoopProxy<T: 'static> {
     target_window: HWND,
     event_send: Sender<T>,
 }
 unsafe impl<T: Send + 'static> Send for EventLoopProxy<T> {}
 
+impl<T: 'static> Clone for EventLoopProxy<T> {
+    fn clone(&self) -> Self {
+        Self {
+            target_window: self.target_window,
+            event_send: self.event_send.clone(),
+        }
+    }
+}
+
 impl<T: 'static> EventLoopProxy<T> {
     pub fn send_event(&self, event: T) -> Result<(), EventLoopClosed> {
         unsafe {