Consistently pass a ref to a Dispatch

tracing-core/src/dispatcher.rs

@@ -107,7 +107,7 @@
 //! // no default subscriber
 //!
 //! # #[cfg(feature = "std")]
-//! dispatcher::set_global_default(my_dispatch)
+//! dispatcher::set_global_default(&my_dispatch)
 //!     // `set_global_default` will return an error if the global default
 //!     // subscriber has already been set.
 //!     .expect("global default was already set!");
@@ -307,12 +307,12 @@ pub fn set_default(dispatcher: &Dispatch) -> DefaultGuard {
 /// [span]: super::span
 /// [`Subscriber`]: super::subscriber::Subscriber
 /// [`Event`]: super::event::Event
-pub fn set_global_default(dispatcher: Dispatch) -> Result<(), SetGlobalDefaultError> {
+pub fn set_global_default(dispatcher: &Dispatch) -> Result<(), SetGlobalDefaultError> {
     if GLOBAL_INIT.compare_and_swap(UNINITIALIZED, INITIALIZING, Ordering::SeqCst) == UNINITIALIZED
     {
         #[cfg(feature = "alloc")]
         let subscriber = {
-            let subscriber = match dispatcher.subscriber {
+            let subscriber = match dispatcher.subscriber.clone() {
                 Kind::Global(s) => s,
                 Kind::Scoped(s) => unsafe {
                     // safety: this leaks the subscriber onto the heap. the
@@ -527,7 +527,7 @@ impl Dispatch {
     ///
     ///     let dispatch = Dispatch::from_static(&SUBSCRIBER);
     ///
-    ///     dispatcher::set_global_default(dispatch)
+    ///     dispatcher::set_global_default(&dispatch)
     ///         .expect("no global default subscriber should have been set previously!");
     /// }
     /// ```

tracing-core/tests/dispatch.rs

@@ -9,7 +9,7 @@ use tracing_core::dispatcher::*;
 #[cfg(feature = "std")]
 #[test]
 fn set_default_dispatch() {
-    set_global_default(Dispatch::new(TestSubscriberA)).expect("global dispatch set failed");
+    set_global_default(&Dispatch::new(TestSubscriberA)).expect("global dispatch set failed");
     get_default(|current| {
         assert!(
             current.is::<TestSubscriberA>(),

tracing-core/tests/global_dispatch.rs

@@ -5,7 +5,7 @@ use tracing_core::dispatcher::*;
 #[test]
 fn global_dispatch() {
     static TEST: TestSubscriberA = TestSubscriberA;
-    set_global_default(Dispatch::from_static(&TEST)).expect("global dispatch set failed");
+    set_global_default(&Dispatch::from_static(&TEST)).expect("global dispatch set failed");
     get_default(|current| {
         assert!(
             current.is::<TestSubscriberA>(),
@@ -30,6 +30,6 @@ fn global_dispatch() {
         )
     });
 
-    set_global_default(Dispatch::from_static(&TEST))
+    set_global_default(&Dispatch::from_static(&TEST))
         .expect_err("double global dispatch set succeeded");
 }

tracing-subscriber/src/fmt/mod.rs

@@ -415,7 +415,7 @@ where
         #[cfg(feature = "tracing-log")]
         tracing_log::LogTracer::init().map_err(Box::new)?;
 
-        tracing_core::dispatcher::set_global_default(tracing_core::dispatcher::Dispatch::new(
+        tracing_core::dispatcher::set_global_default(&tracing_core::dispatcher::Dispatch::new(
             self.finish(),
         ))?;
         Ok(())

tracing-subscriber/src/util.rs

@@ -53,7 +53,7 @@ where
         #[cfg(feature = "tracing-log")]
         tracing_log::LogTracer::init().map_err(TryInitError::new)?;
 
-        dispatcher::set_global_default(self.into()).map_err(TryInitError::new)?;
+        dispatcher::set_global_default(&self.into()).map_err(TryInitError::new)?;
 
         Ok(())
     }

tracing/src/dispatcher.rs

@@ -108,7 +108,7 @@
 //! // no default subscriber
 //!
 //! # #[cfg(feature = "alloc")]
-//! dispatcher::set_global_default(my_dispatch)
+//! dispatcher::set_global_default(&my_dispatch)
 //!     // `set_global_default` will return an error if the global default
 //!     // subscriber has already been set.
 //!     .expect("global default was already set!");

tracing/src/subscriber.rs

@@ -42,7 +42,7 @@ pub fn set_global_default<S>(subscriber: S) -> Result<(), SetGlobalDefaultError>
 where
     S: Subscriber + Send + Sync + 'static,
 {
-    crate::dispatcher::set_global_default(crate::Dispatch::new(subscriber))
+    crate::dispatcher::set_global_default(&crate::Dispatch::new(subscriber))
 }
 
 /// Sets the subscriber as the default for the duration of the lifetime of the