fix: create separate test_support crates to eliminate #[allow(dead_code)] (#1667)

Because of a quirk of how implementation tests work in Rust, we had a
number of `#[allow(dead_code)]` annotations that were misleading because
the functions _were_ being used, just not by all integration tests in a
`tests/` folder, so when compiling the test that did not use the
function, clippy would complain that it was unused.

This fixes things by create a "test_support" crate under the `tests/`
folder that is imported as a dev dependency for the respective crate.

codex-rs/core/tests/client.rs

@@ -5,10 +5,10 @@ use codex_core::protocol::EventMsg;
 use codex_core::protocol::InputItem;
 use codex_core::protocol::Op;
 use codex_core::protocol::SessionConfiguredEvent;
-mod test_support;
+use core_test_support::load_default_config_for_test;
+use core_test_support::load_sse_fixture_with_id;
+use core_test_support::wait_for_event;
 use tempfile::TempDir;
-use test_support::load_default_config_for_test;
-use test_support::load_sse_fixture_with_id;
 use wiremock::Mock;
 use wiremock::MockServer;
 use wiremock::ResponseTemplate;
@@ -84,14 +84,13 @@ async fn includes_session_id_and_model_headers_in_request() {
         .unwrap();
 
     let EventMsg::SessionConfigured(SessionConfiguredEvent { session_id, .. }) =
-        test_support::wait_for_event(&codex, |ev| matches!(ev, EventMsg::SessionConfigured(_)))
-            .await
+        wait_for_event(&codex, |ev| matches!(ev, EventMsg::SessionConfigured(_))).await
     else {
         unreachable!()
     };
 
     let current_session_id = Some(session_id.to_string());
-    test_support::wait_for_event(&codex, |ev| matches!(ev, EventMsg::TaskComplete(_))).await;
+    wait_for_event(&codex, |ev| matches!(ev, EventMsg::TaskComplete(_))).await;
 
     // get request from the server
     let request = &server.received_requests().await.unwrap()[0];
@@ -160,7 +159,7 @@ async fn includes_base_instructions_override_in_request() {
         .await
         .unwrap();
 
-    test_support::wait_for_event(&codex, |ev| matches!(ev, EventMsg::TaskComplete(_))).await;
+    wait_for_event(&codex, |ev| matches!(ev, EventMsg::TaskComplete(_))).await;
 
     let request = &server.received_requests().await.unwrap()[0];
     let request_body = request.body_json::<serde_json::Value>().unwrap();

codex-rs/core/tests/common/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "core_test_support"
+version = { workspace = true }
+edition = "2024"
+
+[lib]
+path = "lib.rs"
+
+[dependencies]
+codex-core = { path = "../.." }
+serde_json = "1"
+tempfile = "3"
+tokio = { version = "1", features = ["time"] }

codex-rs/core/tests/common/lib.rs

@@ -1,9 +1,5 @@
 #![allow(clippy::expect_used)]
 
-// Helpers shared by the integration tests.  These are located inside the
-// `tests/` tree on purpose so they never become part of the public API surface
-// of the `codex-core` crate.
-
 use tempfile::TempDir;
 
 use codex_core::config::Config;
@@ -30,7 +26,6 @@ pub fn load_default_config_for_test(codex_home: &TempDir) -> Config {
 /// with only a `type` field results in an event with no `data:` section. This
 /// makes it trivial to extend the fixtures as OpenAI adds new event kinds or
 /// fields.
-#[allow(dead_code)]
 pub fn load_sse_fixture(path: impl AsRef<std::path::Path>) -> String {
     let events: Vec<serde_json::Value> =
         serde_json::from_reader(std::fs::File::open(path).expect("read fixture"))
@@ -55,7 +50,6 @@ pub fn load_sse_fixture(path: impl AsRef<std::path::Path>) -> String {
 /// fixture template with the supplied identifier before parsing. This lets a
 /// single JSON template be reused by multiple tests that each need a unique
 /// `response_id`.
-#[allow(dead_code)]
 pub fn load_sse_fixture_with_id(path: impl AsRef<std::path::Path>, id: &str) -> String {
     let raw = std::fs::read_to_string(path).expect("read fixture template");
     let replaced = raw.replace("__ID__", id);
@@ -77,7 +71,6 @@ pub fn load_sse_fixture_with_id(path: impl AsRef<std::path::Path>, id: &str) ->
         .collect()
 }
 
-#[allow(dead_code)]
 pub async fn wait_for_event<F>(
     codex: &codex_core::Codex,
     mut predicate: F,

codex-rs/core/tests/live_agent.rs

@@ -26,9 +26,8 @@ use codex_core::protocol::ErrorEvent;
 use codex_core::protocol::EventMsg;
 use codex_core::protocol::InputItem;
 use codex_core::protocol::Op;
-mod test_support;
+use core_test_support::load_default_config_for_test;
 use tempfile::TempDir;
-use test_support::load_default_config_for_test;
 use tokio::sync::Notify;
 use tokio::time::timeout;
 

codex-rs/core/tests/stream_no_completed.rs

@@ -9,11 +9,10 @@ use codex_core::exec::CODEX_SANDBOX_NETWORK_DISABLED_ENV_VAR;
 use codex_core::protocol::EventMsg;
 use codex_core::protocol::InputItem;
 use codex_core::protocol::Op;
-mod test_support;
+use core_test_support::load_default_config_for_test;
+use core_test_support::load_sse_fixture;
+use core_test_support::load_sse_fixture_with_id;
 use tempfile::TempDir;
-use test_support::load_default_config_for_test;
-use test_support::load_sse_fixture;
-use test_support::load_sse_fixture_with_id;
 use tokio::time::timeout;
 use wiremock::Mock;
 use wiremock::MockServer;