Rescue on_event impls from the rebase wastes

tracing-subscriber/src/subscribe/layered.rs

@@ -114,8 +114,10 @@ where
     }
 
     fn event(&self, event: &Event<'_>) {
-        self.inner.event(event);
-        self.subscriber.on_event(event, self.ctx());
+        if self.subscriber.event_enabled(event, self.ctx()) {
+            self.inner.event(event);
+            self.subscriber.on_event(event, self.ctx());
+        }
     }
 
     fn enter(&self, span: &span::Id) {
@@ -255,6 +257,17 @@ where
         self.subscriber.on_follows_from(span, follows, ctx);
     }
 
+    #[inline]
+    fn event_enabled(&self, event: &Event<'_>, ctx: Context<'_, C>) -> bool {
+        if self.subscriber.event_enabled(event, ctx.clone()) {
+            // if the outer subscriber enables the event, ask the inner subscriber.
+            self.inner.event_enabled(event, ctx)
+        } else {
+            // otherwise, the callsite is disabled by this subscriber
+            false
+        }
+    }
+
     #[inline]
     fn on_event(&self, event: &Event<'_>, ctx: Context<'_, C>) {
         self.inner.on_event(event, ctx.clone());

tracing-subscriber/src/subscribe/mod.rs

@@ -1504,6 +1504,14 @@ where
         }
     }
 
+    #[inline]
+    fn event_enabled(&self, event: &Event<'_>, ctx: Context<'_, C>) -> bool {
+        match self {
+            Some(ref inner) => inner.event_enabled(event, ctx),
+            None => false,
+        }
+    }
+
     #[inline]
     fn on_event(&self, event: &Event<'_>, ctx: Context<'_, C>) {
         if let Some(ref inner) = self {
@@ -1583,6 +1591,11 @@ macro_rules! subscriber_impl_body {
             self.deref().on_follows_from(span, follows, ctx)
         }
 
+        #[inline]
+        fn event_enabled(&self, event: &Event<'_>, ctx: Context<'_, C>) -> bool {
+            self.deref().event_enabled(event, ctx)
+        }
+
         #[inline]
         fn on_event(&self, event: &Event<'_>, ctx: Context<'_, C>) {
             self.deref().on_event(event, ctx)