chore(ci): re-enable CI running on beta

.travis.yml

@@ -1,27 +1,27 @@
 language: rust
-#sudo: true # Required for functional IPv6 (forces VM instead of Docker).
+sudo: true # Required for functional IPv6 (forces VM instead of Docker).
 dist: trusty
 matrix:
     fast_finish: true
     include:
         - rust: nightly
-          env: FEATURES="--no-default-features --features runtime,nightly"
-        #- rust: beta
-        #  env: FEATURES="--no-default-features --features runtime,__internal_happy_eyeballs_tests"
+          env: FEATURES="--no-default-features --features runtime,unstable-stream,nightly"
+        - rust: beta
+          env: FEATURES="--no-default-features --features runtime,unstable-stream,__internal_happy_eyeballs_tests"
         #- rust: stable
-        #  env: FEATURES="--no-default-features --features runtime,__internal_happy_eyeballs_tests"
-        - rust: nightly #stable
+        #  env: FEATURES="--no-default-features --features runtime,unstable-stream,__internal_happy_eyeballs_tests"
+        - rust: beta #stable
           env: FEATURES="--no-default-features"
         # Minimum Supported Rust Version
-        #- rust: 1.36.0
+        #- rust: 1.39.0
         #  env: FEATURES="--no-default-features --features runtime" BUILD_ONLY="1"
 
-#before_script:
+before_script:
   # Add an IPv6 config - see the corresponding Travis issue
   # https://github.com/travis-ci/travis-ci/issues/83
-  #- if [ "${TRAVIS_OS_NAME}" == "linux" ]; then
-  #    sudo sh -c 'echo 0 > /proc/sys/net/ipv6/conf/all/disable_ipv6';
-  #  fi
+  - if [ "${TRAVIS_OS_NAME}" == "linux" ]; then
+      sudo sh -c 'echo 0 > /proc/sys/net/ipv6/conf/all/disable_ipv6';
+    fi
 
 script:
   - 'if [ "$BUILD_ONLY" != "1" ]; then cargo test $FEATURES -- --test-threads=1; fi'

Cargo.toml

@@ -200,4 +200,4 @@ required-features = ["runtime", "unstable-stream"]
 [[test]]
 name = "server"
 path = "tests/server.rs"
-required-features = ["runtime", "unstable-stream"]
+required-features = ["runtime"]

tests/server.rs

@@ -1,6 +1,5 @@
-#![feature(async_closure)]
 #![deny(warnings)]
-#![warn(rust_2018_idioms)]
+#![deny(rust_2018_idioms)]
 
 use std::net::{TcpStream, Shutdown, SocketAddr};
 use std::io::{self, Read, Write};
@@ -19,7 +18,7 @@ use futures_core::future::BoxFuture;
 use futures_util::future::{self, Either, FutureExt};
 use futures_util::stream::StreamExt;
 use futures_util::try_future::{self, TryFutureExt};
-use futures_util::try_stream::TryStreamExt;
+//use futures_util::try_stream::TryStreamExt;
 use http::header::{HeaderName, HeaderValue};
 use tokio_net::driver::Handle;
 use tokio_net::tcp::{TcpListener, TcpStream as TkTcpStream};
@@ -1469,6 +1468,7 @@ fn max_buf_size() {
     rt.block_on(fut).expect_err("should TooLarge error");
 }
 
+#[cfg(feature = "unstable-stream")]
 #[test]
 fn streaming_body() {
     let _ = pretty_env_logger::try_init();
@@ -1584,6 +1584,7 @@ fn http2_service_error_sends_reset_reason() {
     assert_eq!(h2_err.reason(), Some(h2::Reason::INADEQUATE_SECURITY));
 }
 
+#[cfg(feature = "unstable-stream")]
 #[test]
 fn http2_body_user_error_sends_reset_reason() {
     use std::error::Error;
@@ -1601,15 +1602,18 @@ fn http2_body_user_error_sends_reset_reason() {
 
     let mut rt = Runtime::new().expect("runtime new");
 
-    let err = rt.block_on({
+    let err: hyper::Error = rt.block_on(async move {
         let client = Client::builder()
             .http2_only(true)
             .build_http::<hyper::Body>();
         let uri = addr_str.parse().expect("server addr should parse");
 
-        client
-            .get(uri)
-            .and_then(|res| res.into_body().try_concat())
+        let mut res = client.get(uri).await?;
+
+        while let Some(chunk) = res.body_mut().next().await {
+            chunk?;
+        }
+        Ok(())
     }).unwrap_err();
 
     let h2_err = err