test(client): update test helpers to handle fallible packet length calculations

crates/irtt-client/tests/hmac.rs

@@ -13,6 +13,8 @@ use support::{
     start_hmac_required_open_drop_server, BackendPeer, ServerObservation, TOKEN,
 };
 
+use crate::support::test_echo_packet_len;
+
 #[test]
 fn hmac_open_success_negotiates_without_warnings() {
     let key = b"compat-secret".to_vec();

crates/irtt-client/tests/large_packets.rs

@@ -1,10 +1,12 @@
 mod support;
 
 use irtt_client::{Client, ClientConfig, ClientEvent, NegotiationPolicy};
-use irtt_proto::{echo_header_len, echo_packet_len, Params, TimestampFields};
+use irtt_proto::{echo_header_len, Params, TimestampFields};
 
 use support::{config_for_params, default_params, run_one_probe, BackendPeer, ServerObservation};
 
+use crate::support::test_echo_packet_len;
+
 fn params_with_length(length: i64) -> Params {
     Params {
         length,

crates/irtt-client/tests/protocol_options.rs

@@ -14,6 +14,8 @@ use support::{
     ServerObservation, RECV_COUNT, RECV_WINDOW, TOKEN,
 };
 
+use crate::support::test_echo_packet_len;
+
 struct ReplyView<'a> {
     seq: u32,
     rtt: &'a RttSample,

crates/irtt-client/tests/server_fill.rs

@@ -1,13 +1,15 @@
 mod support;
 
 use irtt_client::{Client, ClientConfig, ClientError, ClientEvent, NegotiationPolicy};
-use irtt_proto::{echo_packet_len, Params, TimestampFields};
+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,
 };
 
+use crate::support::test_echo_packet_len;
+
 fn open_observation_params(run: &OneProbeRun) -> &Params {
     match &run.observations[0] {
         ServerObservation::Open { params, .. } => params,

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

@@ -520,6 +520,11 @@ fn open_reply(flags: u8, token: u64, params: &Params, hmac_key: Option<&[u8]>) -
     packet
 }
 
+pub(super) fn test_echo_packet_len(hmac: bool, params: &Params) -> usize {
+    echo_packet_len(hmac, params)
+        .expect("managed runner test params must have a non-negative packet length")
+}
+
 fn echo_reply_packet(
     token: u64,
     seq: u32,