Remove async-await feature of futures.

zebra-network/Cargo.toml

@@ -21,7 +21,7 @@ pin-project = "0.4"
 indexmap = { version = "1.2", default-features = false }
 
 tokio = "=0.2.0-alpha.6"
-futures-preview = { version = "=0.3.0-alpha.19", features = ["async-await"] }
+futures-preview = "=0.3.0-alpha.19"
 
 tracing = "0.1"
 tracing-futures = { version = "0.1", features = ["tokio-alpha"], default-features = false }

zebra-network/src/timestamp_collector.rs

@@ -87,21 +87,15 @@ impl TimestampCollector {
 
         // Construct and then spawn a worker.
         let worker = async move {
-            use futures::select;
+            use futures::future::{self, Either};
             loop {
-                select! {
+                match future::select(shutdown_rx.next(), worker_rx.next()).await {
-                    _ = shutdown_rx.next() => return,
+                    Either::Left((_, _)) => return,     // shutdown signal
-                    msg = worker_rx.next() => {
+                    Either::Right((None, _)) => return, // all workers are gone
-                        match msg {
+                    Either::Right((Some(event), _)) => data2
-                            Some(event) => {
+                        .lock()
-                                data2
+                        .expect("mutex should be unpoisoned")
-                                    .lock()
+                        .update(event),
-                                    .expect("mutex should be unpoisoned")
-                                    .update(event)
-                            }
-                            None => return,
-                        }
-                    }
                 }
             }
         };

zebrad/Cargo.toml

@@ -15,7 +15,7 @@ serde = { version = "1", features = ["serde_derive"] }
 toml = "0.5"
 
 tokio = "=0.2.0-alpha.6"
-futures-preview = { version = "=0.3.0-alpha.19", features = ["async-await"] }
+futures-preview = "=0.3.0-alpha.19"
 
 tracing = "0.1"
 tracing-futures = { version = "0.1", features = ["tokio-alpha"], default-features = false }