test(client): use real server for compliant peers

crates/irtt-client/tests/hmac.rs

@@ -276,7 +276,7 @@ fn assert_no_duplicate_late_or_warning(events: &[ClientEvent]) {
 fn backend_hmac_correct_key_succeeds() {
     let key = b"compat-secret".to_vec();
     let params = default_params();
-    let peer = BackendPeer::start_open_echo(params.clone(), Some(key.clone()));
+    let peer = BackendPeer::start_open_echo(Some(key.clone()));
     let mut config = config_for_params(peer.addr(), &params);
     config.hmac_key = Some(key);
 

crates/irtt-client/tests/large_packets.rs

@@ -83,7 +83,7 @@ fn echo_reply_bytes_consistent_with_echo_packet_len_for_various_lengths() {
 #[test]
 fn backend_large_packet_smoke() {
     let params = params_with_length(1472);
-    let peer = BackendPeer::start_open_echo(params.clone(), None);
+    let peer = BackendPeer::start_open_echo(None);
     let mut client = Client::connect(ClientConfig {
         negotiation_policy: NegotiationPolicy::Loose,
         length: 1472,

crates/irtt-client/tests/protocol_options/backend_smoke.rs

@@ -6,7 +6,7 @@ use crate::support::{config_for_params, default_params, params_for_modes, Backen
 #[test]
 fn backend_basic_open_echo_close() {
     let params = default_params();
-    let peer = BackendPeer::start_open_echo(params.clone(), None);
+    let peer = BackendPeer::start_open_echo(None);
     let mut client = Client::connect(config_for_params(peer.addr(), &params)).unwrap();
 
     let outcome = client.open().unwrap();
@@ -31,7 +31,7 @@ fn backend_received_stats_smoke() {
         ReceivedStats::Both,
     ] {
         let params = params_for_modes(mode, StampAt::None, Clock::Both);
-        let peer = BackendPeer::start_open_echo(params.clone(), None);
+        let peer = BackendPeer::start_open_echo(None);
         let mut client = Client::connect(config_for_params(peer.addr(), &params)).unwrap();
 
         client.open().unwrap();
@@ -54,7 +54,7 @@ fn backend_timestamp_smoke() {
         StampAt::Midpoint,
     ] {
         let params = params_for_modes(ReceivedStats::None, mode, Clock::Both);
-        let peer = BackendPeer::start_open_echo(params.clone(), None);
+        let peer = BackendPeer::start_open_echo(None);
         let mut client = Client::connect(config_for_params(peer.addr(), &params)).unwrap();
 
         client.open().unwrap();
@@ -101,7 +101,7 @@ fn backend_timestamp_smoke() {
 fn backend_clock_smoke() {
     for clock in [Clock::Wall, Clock::Monotonic, Clock::Both] {
         let params = params_for_modes(ReceivedStats::None, StampAt::Both, clock);
-        let peer = BackendPeer::start_open_echo(params.clone(), None);
+        let peer = BackendPeer::start_open_echo(None);
         let mut client = Client::connect(config_for_params(peer.addr(), &params)).unwrap();
 
         client.open().unwrap();

crates/irtt-client/tests/server_fill.rs

@@ -5,7 +5,7 @@ use irtt_proto::{Params, TimestampFields};
 
 use support::{
     config_for_params, default_params, run_one_probe, run_one_probe_with_config, server_fill,
-    start_open_server, OneProbeRun, ServerObservation,
+    start_open_server, InTreeServer, OneProbeRun, ServerObservation,
 };
 
 use crate::support::test_echo_packet_len;
@@ -68,8 +68,21 @@ fn server_fill_empty_and_oversized_values_are_rejected_at_config_boundary() {
 fn server_fill_negotiated_params_reflect_accepted_value() {
     let mut params = default_params();
     params.server_fill = server_fill("rand");
-    let run = run_one_probe(params.clone(), TimestampFields::default());
-    assert_eq!(run.negotiated.params.server_fill, params.server_fill);
+    let server = InTreeServer::start(irtt_server::ServerConfig::default());
+    let mut client = Client::connect(config_for_params(server.addr, &params)).unwrap();
+    let outcome = client.open().unwrap();
+    let negotiated = match outcome {
+        irtt_client::OpenOutcome::Started { negotiated, .. } => negotiated,
+        other => panic!("expected started outcome, got {other:?}"),
+    };
+    assert_eq!(negotiated.params.server_fill, params.server_fill);
+
+    client.send_probe().unwrap();
+    assert!(matches!(
+        client.recv_once().unwrap().as_slice(),
+        [irtt_client::ClientEvent::EchoReply { .. }]
+    ));
+    client.close().unwrap();
 }
 
 #[test]

crates/irtt-client/tests/support/in_tree_server.rs

@@ -0,0 +1,99 @@
+use std::{
+    net::{IpAddr, Ipv4Addr, SocketAddr},
+    sync::mpsc,
+    thread::{self, JoinHandle},
+    time::Duration,
+};
+
+use irtt_server::{Server, ServerConfig};
+use tokio::sync::oneshot;
+
+const STARTUP_TIMEOUT: Duration = Duration::from_secs(2);
+
+pub struct InTreeServer {
+    pub addr: SocketAddr,
+    shutdown: Option<oneshot::Sender<()>>,
+    done: Option<JoinHandle<Result<(), String>>>,
+}
+
+impl InTreeServer {
+    pub fn start(config: ServerConfig) -> Self {
+        let (startup_tx, startup_rx) = mpsc::sync_channel(1);
+        let (shutdown_tx, shutdown_rx) = oneshot::channel();
+        let done = thread::spawn(move || {
+            let runtime = tokio::runtime::Builder::new_current_thread()
+                .enable_all()
+                .build()
+                .map_err(|error| format!("failed to build test server runtime: {error}"))?;
+            runtime.block_on(async move {
+                let bind_addr = SocketAddr::new(IpAddr::V4(Ipv4Addr::LOCALHOST), 0);
+                let mut server = match Server::bind(bind_addr, config).await {
+                    Ok(server) => server,
+                    Err(error) => {
+                        let message = format!("failed to bind in-tree test server: {error}");
+                        let _ = startup_tx.send(Err(message.clone()));
+                        return Err(message);
+                    }
+                };
+                let addr = match server.local_addr() {
+                    Ok(addr) => addr,
+                    Err(error) => {
+                        let message =
+                            format!("failed to read in-tree test server address: {error}");
+                        let _ = startup_tx.send(Err(message.clone()));
+                        return Err(message);
+                    }
+                };
+                startup_tx
+                    .send(Ok(addr))
+                    .map_err(|_| "test stopped waiting for in-tree server startup".to_owned())?;
+                server
+                    .run(async {
+                        let _ = shutdown_rx.await;
+                    })
+                    .await
+                    .map_err(|error| format!("in-tree test server failed: {error}"))
+            })
+        });
+
+        let addr = match startup_rx.recv_timeout(STARTUP_TIMEOUT) {
+            Ok(Ok(addr)) => addr,
+            Ok(Err(error)) => {
+                done.join()
+                    .expect("in-tree test server thread panicked")
+                    .ok();
+                panic!("{error}");
+            }
+            Err(error) => {
+                let _ = shutdown_tx.send(());
+                done.join()
+                    .expect("in-tree test server thread panicked")
+                    .ok();
+                panic!("timed out waiting for in-tree test server startup: {error}");
+            }
+        };
+
+        Self {
+            addr,
+            shutdown: Some(shutdown_tx),
+            done: Some(done),
+        }
+    }
+
+    fn stop_inner(&mut self) {
+        if let Some(shutdown) = self.shutdown.take() {
+            let _ = shutdown.send(());
+        }
+        if let Some(done) = self.done.take() {
+            done.join()
+                .expect("in-tree test server thread panicked")
+                .expect("in-tree test server stopped with an error");
+        }
+    }
+}
+
+impl Drop for InTreeServer {
+    fn drop(&mut self) {
+        self.stop_inner();
+    }
+}

crates/irtt-client/tests/support/mod.rs

@@ -1,5 +1,6 @@
 #![allow(dead_code)]
 
+mod in_tree_server;
 mod real_irtt;
 
 use std::{
@@ -17,7 +18,9 @@ use irtt_proto::{
     PacketLayout, Params, ProtoError, ReceivedStats, ServerFill, StampAt, TimestampFields,
     HMAC_SIZE, MAGIC, PROTOCOL_VERSION,
 };
+use irtt_server::ServerConfig;
 
+pub use in_tree_server::InTreeServer;
 pub use real_irtt::RealIrtServer;
 
 const HMAC_OFFSET: usize = 4;
@@ -27,7 +30,7 @@ pub const RECV_WINDOW: u64 = 0x07;
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum TestBackendKind {
-    Fake,
+    InTree,
     Real,
 }
 
@@ -43,9 +46,9 @@ pub fn selected_backend() -> TestBackendKind {
                 _ => panic!("IRTT_TEST_BACKEND=real but irtt binary not found at '{irtt_bin}'"),
             }
         }
-        Ok("fake") | Err(_) => {
-            debug_backend("[backend] selected backend=fake");
-            TestBackendKind::Fake
+        Ok("in-tree") | Err(_) => {
+            debug_backend("[backend] selected backend=in-tree");
+            TestBackendKind::InTree
         }
         Ok(other) => panic!("unknown IRTT_TEST_BACKEND value: {other}"),
     }
@@ -58,24 +61,25 @@ fn debug_backend(message: &str) {
 }
 
 pub enum BackendPeer {
-    Fake(FakeServer),
+    InTree(InTreeServer),
     Real(RealIrtServer),
 }
 
 impl BackendPeer {
     pub fn addr(&self) -> SocketAddr {
         match self {
-            BackendPeer::Fake(s) => s.addr,
+            BackendPeer::InTree(s) => s.addr,
             BackendPeer::Real(s) => s.addr(),
         }
     }
 
-    pub fn start_open_echo(params: Params, hmac_key: Option<Vec<u8>>) -> Self {
+    pub fn start_open_echo(hmac_key: Option<Vec<u8>>) -> Self {
         match selected_backend() {
-            TestBackendKind::Fake => {
-                let timestamps = standard_timestamps();
-                BackendPeer::Fake(start_one_probe_server(params, timestamps, hmac_key))
-            }
+            TestBackendKind::InTree => BackendPeer::InTree(InTreeServer::start(
+                hmac_key.map_or_else(ServerConfig::default, |key| {
+                    ServerConfig::default().with_hmac_key(key)
+                }),
+            )),
             TestBackendKind::Real => {
                 BackendPeer::Real(RealIrtServer::start(hmac_key.as_deref()).unwrap())
             }
@@ -84,9 +88,8 @@ impl BackendPeer {
 
     pub fn start_hmac_required(key: Vec<u8>) -> Self {
         match selected_backend() {
-            TestBackendKind::Fake => BackendPeer::Fake(start_hmac_required_open_drop_server(
-                key,
-                Duration::from_millis(250),
+            TestBackendKind::InTree => BackendPeer::InTree(InTreeServer::start(
+                ServerConfig::default().with_hmac_key(key),
             )),
             TestBackendKind::Real => BackendPeer::Real(RealIrtServer::start(Some(&key)).unwrap()),
         }