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/mcp-server/Cargo.toml

@@ -37,6 +37,7 @@ uuid = { version = "1", features = ["serde", "v4"] }
 
 [dev-dependencies]
 assert_cmd = "2"
+mcp_test_support = { path = "tests/common" }
 pretty_assertions = "1.4.1"
 tempfile = "3"
 tokio-test = "0.4"

codex-rs/mcp-server/tests/codex_tool.rs

@@ -1,5 +1,3 @@
-mod common;
-
 use std::collections::HashMap;
 use std::env;
 use std::path::Path;
@@ -26,11 +24,11 @@ use tempfile::TempDir;
 use tokio::time::timeout;
 use wiremock::MockServer;
 
-use crate::common::McpProcess;
-use crate::common::create_apply_patch_sse_response;
-use crate::common::create_final_assistant_message_sse_response;
-use crate::common::create_mock_chat_completions_server;
-use crate::common::create_shell_sse_response;
+use mcp_test_support::McpProcess;
+use mcp_test_support::create_apply_patch_sse_response;
+use mcp_test_support::create_final_assistant_message_sse_response;
+use mcp_test_support::create_mock_chat_completions_server;
+use mcp_test_support::create_shell_sse_response;
 
 const DEFAULT_READ_TIMEOUT: std::time::Duration = std::time::Duration::from_secs(10);
 

codex-rs/mcp-server/tests/common/Cargo.toml

@@ -0,0 +1,24 @@
+[package]
+name = "mcp_test_support"
+version = { workspace = true }
+edition = "2024"
+
+[lib]
+path = "lib.rs"
+
+[dependencies]
+anyhow = "1"
+assert_cmd = "2"
+codex-mcp-server = { path = "../.." }
+mcp-types = { path = "../../../mcp-types" }
+pretty_assertions = "1.4.1"
+serde_json = "1"
+shlex = "1.3.0"
+tempfile = "3"
+tokio = { version = "1", features = [
+    "io-std",
+    "macros",
+    "process",
+    "rt-multi-thread",
+] }
+wiremock = "0.6"

codex-rs/mcp-server/tests/common/lib.rs

@@ -4,8 +4,6 @@ mod responses;
 
 pub use mcp_process::McpProcess;
 pub use mock_model_server::create_mock_chat_completions_server;
-#[allow(unused_imports)]
 pub use responses::create_apply_patch_sse_response;
-#[allow(unused_imports)]
 pub use responses::create_final_assistant_message_sse_response;
 pub use responses::create_shell_sse_response;

codex-rs/mcp-server/tests/common/mcp_process.rs

@@ -191,8 +191,6 @@ impl McpProcess {
         Ok(request_id)
     }
 
-    // allow dead code
-    #[allow(dead_code)]
     pub async fn send_response(
         &mut self,
         id: RequestId,
@@ -220,8 +218,6 @@ impl McpProcess {
         let message = serde_json::from_str::<JSONRPCMessage>(&line)?;
         Ok(message)
     }
-    // allow dead code
-    #[allow(dead_code)]
     pub async fn read_stream_until_request_message(&mut self) -> anyhow::Result<JSONRPCRequest> {
         loop {
             let message = self.read_jsonrpc_message().await?;
@@ -244,8 +240,6 @@ impl McpProcess {
         }
     }
 
-    // allow dead code
-    #[allow(dead_code)]
     pub async fn read_stream_until_response_message(
         &mut self,
         request_id: RequestId,
@@ -312,8 +306,6 @@ impl McpProcess {
         }
     }
 
-    // allow dead code
-    #[allow(dead_code)]
     pub async fn send_notification(
         &mut self,
         method: &str,

codex-rs/mcp-server/tests/common/responses.rs

@@ -39,8 +39,6 @@ pub fn create_shell_sse_response(
     Ok(sse)
 }
 
-// allow dead code
-#[allow(dead_code)]
 pub fn create_final_assistant_message_sse_response(message: &str) -> anyhow::Result<String> {
     let assistant_message = json!({
         "choices": [
@@ -60,8 +58,6 @@ pub fn create_final_assistant_message_sse_response(message: &str) -> anyhow::Res
     Ok(sse)
 }
 
-// allow dead code
-#[allow(dead_code)]
 pub fn create_apply_patch_sse_response(
     patch_content: &str,
     call_id: &str,

codex-rs/mcp-server/tests/interrupt.rs

@@ -1,5 +1,5 @@
 #![cfg(unix)]
-mod common;
+// Support code lives in the `mcp_test_support` crate under tests/common.
 
 use std::path::Path;
 
@@ -11,9 +11,9 @@ use serde_json::json;
 use tempfile::TempDir;
 use tokio::time::timeout;
 
-use crate::common::McpProcess;
-use crate::common::create_mock_chat_completions_server;
-use crate::common::create_shell_sse_response;
+use mcp_test_support::McpProcess;
+use mcp_test_support::create_mock_chat_completions_server;
+use mcp_test_support::create_shell_sse_response;
 
 const DEFAULT_READ_TIMEOUT: std::time::Duration = std::time::Duration::from_secs(10);