Add notifier tests (#4064)

Proposal:
1. Use anyhow for tests and avoid unwrap
2. Extract a helper for starting a test instance of codex

codex-rs/Cargo.lock

@@ -1076,6 +1076,7 @@ checksum = "773648b94d0e5d620f64f280777445740e61fe701025087ec8b57f45c791888b"
 name = "core_test_support"
 version = "0.0.0"
 dependencies = [
+ "anyhow",
  "codex-core",
  "serde_json",
  "tempfile",

codex-rs/core/src/codex.rs

@@ -11,6 +11,7 @@ use crate::AuthManager;
 use crate::client_common::REVIEW_PROMPT;
 use crate::event_mapping::map_response_item_to_event_messages;
 use crate::review_format::format_review_findings_block;
+use crate::user_notification::UserNotifier;
 use async_channel::Receiver;
 use async_channel::Sender;
 use codex_apply_patch::ApplyPatchAction;
@@ -186,7 +187,7 @@ impl Codex {
             base_instructions: config.base_instructions.clone(),
             approval_policy: config.approval_policy,
             sandbox_policy: config.sandbox_policy.clone(),
-            notify: config.notify.clone(),
+            notify: UserNotifier::new(config.notify.clone()),
             cwd: config.cwd.clone(),
         };
 
@@ -274,9 +275,7 @@ pub(crate) struct Session {
     session_manager: ExecSessionManager,
     unified_exec_manager: UnifiedExecSessionManager,
 
-    /// External notifier command (will be passed as args to exec()). When
-    /// `None` this feature is disabled.
-    notify: Option<Vec<String>>,
+    notifier: UserNotifier,
 
     /// Optional rollout recorder for persisting the conversation transcript so
     /// sessions can be replayed or inspected later.
@@ -335,10 +334,7 @@ struct ConfigureSession {
     /// How to sandbox commands executed in the system
     sandbox_policy: SandboxPolicy,
 
-    /// Optional external notifier command tokens. Present only when the
-    /// client wants the agent to spawn a program after each completed
-    /// turn.
-    notify: Option<Vec<String>>,
+    notify: UserNotifier,
 
     /// Working directory that should be treated as the *root* of the
     /// session. All relative paths supplied by the model as well as the
@@ -480,7 +476,7 @@ impl Session {
             mcp_connection_manager,
             session_manager: ExecSessionManager::default(),
             unified_exec_manager: UnifiedExecSessionManager::default(),
-            notify,
+            notifier: notify,
             state: Mutex::new(state),
             rollout: Mutex::new(Some(rollout_recorder)),
             codex_linux_sandbox_exe: config.codex_linux_sandbox_exe.clone(),
@@ -586,7 +582,7 @@ impl Session {
         command: Vec<String>,
         cwd: PathBuf,
         reason: Option<String>,
-    ) -> oneshot::Receiver<ReviewDecision> {
+    ) -> ReviewDecision {
         // Add the tx_approve callback to the map before sending the request.
         let (tx_approve, rx_approve) = oneshot::channel();
         let event_id = sub_id.clone();
@@ -608,7 +604,7 @@ impl Session {
             }),
         };
         self.send_event(event).await;
-        rx_approve
+        rx_approve.await.unwrap_or_default()
     }
 
     pub async fn request_patch_approval(
@@ -1034,33 +1030,8 @@ impl Session {
         }
     }
 
-    /// Spawn the configured notifier (if any) with the given JSON payload as
-    /// the last argument. Failures are logged but otherwise ignored so that
-    /// notification issues do not interfere with the main workflow.
-    fn maybe_notify(&self, notification: UserNotification) {
-        let Some(notify_command) = &self.notify else {
-            return;
-        };
-
-        if notify_command.is_empty() {
-            return;
-        }
-
-        let Ok(json) = serde_json::to_string(&notification) else {
-            error!("failed to serialise notification payload");
-            return;
-        };
-
-        let mut command = std::process::Command::new(&notify_command[0]);
-        if notify_command.len() > 1 {
-            command.args(&notify_command[1..]);
-        }
-        command.arg(json);
-
-        // Fire-and-forget – we do not wait for completion.
-        if let Err(e) = command.spawn() {
-            warn!("failed to spawn notifier '{}': {e}", notify_command[0]);
-        }
+    pub(crate) fn notifier(&self) -> &UserNotifier {
+        &self.notifier
     }
 }
 
@@ -1883,11 +1854,12 @@ async fn run_task(
                     last_agent_message = get_last_assistant_message_from_turn(
                         &items_to_record_in_conversation_history,
                     );
-                    sess.maybe_notify(UserNotification::AgentTurnComplete {
-                        turn_id: sub_id.clone(),
-                        input_messages: turn_input_messages,
-                        last_assistant_message: last_agent_message.clone(),
-                    });
+                    sess.notifier()
+                        .notify(&UserNotification::AgentTurnComplete {
+                            turn_id: sub_id.clone(),
+                            input_messages: turn_input_messages,
+                            last_assistant_message: last_agent_message.clone(),
+                        });
                     break;
                 }
                 continue;
@@ -2842,7 +2814,7 @@ async fn handle_container_exec_with_params(
     let sandbox_type = match safety {
         SafetyCheck::AutoApprove { sandbox_type } => sandbox_type,
         SafetyCheck::AskUser => {
-            let rx_approve = sess
+            let decision = sess
                 .request_command_approval(
                     sub_id.clone(),
                     call_id.clone(),
@@ -2851,7 +2823,7 @@ async fn handle_container_exec_with_params(
                     params.justification.clone(),
                 )
                 .await;
-            match rx_approve.await.unwrap_or_default() {
+            match decision {
                 ReviewDecision::Approved => (),
                 ReviewDecision::ApprovedForSession => {
                     sess.add_approved_command(params.command.clone()).await;
@@ -3012,7 +2984,7 @@ async fn handle_sandbox_error(
     sess.notify_background_event(&sub_id, format!("Execution failed: {error}"))
         .await;
 
-    let rx_approve = sess
+    let decision = sess
         .request_command_approval(
             sub_id.clone(),
             call_id.clone(),
@@ -3022,7 +2994,7 @@ async fn handle_sandbox_error(
         )
         .await;
 
-    match rx_approve.await.unwrap_or_default() {
+    match decision {
         ReviewDecision::Approved | ReviewDecision::ApprovedForSession => {
             // Persist this command as pre‑approved for the
             // remainder of the session so future
@@ -3642,7 +3614,7 @@ mod tests {
             mcp_connection_manager: McpConnectionManager::default(),
             session_manager: ExecSessionManager::default(),
             unified_exec_manager: UnifiedExecSessionManager::default(),
-            notify: None,
+            notifier: UserNotifier::default(),
             rollout: Mutex::new(None),
             state: Mutex::new(State {
                 history: ConversationHistory::new(),

codex-rs/core/src/user_notification.rs

@@ -1,4 +1,45 @@
 use serde::Serialize;
+use tracing::error;
+use tracing::warn;
+
+#[derive(Debug, Default)]
+pub(crate) struct UserNotifier {
+    notify_command: Option<Vec<String>>,
+}
+
+impl UserNotifier {
+    pub(crate) fn notify(&self, notification: &UserNotification) {
+        if let Some(notify_command) = &self.notify_command
+            && !notify_command.is_empty()
+        {
+            self.invoke_notify(notify_command, notification)
+        }
+    }
+
+    fn invoke_notify(&self, notify_command: &[String], notification: &UserNotification) {
+        let Ok(json) = serde_json::to_string(&notification) else {
+            error!("failed to serialise notification payload");
+            return;
+        };
+
+        let mut command = std::process::Command::new(&notify_command[0]);
+        if notify_command.len() > 1 {
+            command.args(&notify_command[1..]);
+        }
+        command.arg(json);
+
+        // Fire-and-forget – we do not wait for completion.
+        if let Err(e) = command.spawn() {
+            warn!("failed to spawn notifier '{}': {e}", notify_command[0]);
+        }
+    }
+
+    pub(crate) fn new(notify: Option<Vec<String>>) -> Self {
+        Self {
+            notify_command: notify,
+        }
+    }
+}
 
 /// User can configure a program that will receive notifications. Each
 /// notification is serialized as JSON and passed as an argument to the

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

@@ -1,12 +1,13 @@
 [package]
+edition = "2024"
 name = "core_test_support"
 version = { workspace = true }
-edition = "2024"
 
 [lib]
 path = "lib.rs"
 
 [dependencies]
+anyhow = { workspace = true }
 codex-core = { workspace = true }
 serde_json = { workspace = true }
 tempfile = { workspace = true }

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

@@ -8,6 +8,7 @@ use codex_core::config::ConfigOverrides;
 use codex_core::config::ConfigToml;
 
 pub mod responses;
+pub mod test_codex;
 
 /// Returns a default `Config` whose on-disk state is confined to the provided
 /// temporary directory. Using a per-test directory keeps tests hermetic and

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

@@ -0,0 +1,75 @@
+use std::mem::swap;
+use std::sync::Arc;
+
+use codex_core::CodexAuth;
+use codex_core::CodexConversation;
+use codex_core::ConversationManager;
+use codex_core::ModelProviderInfo;
+use codex_core::NewConversation;
+use codex_core::built_in_model_providers;
+use codex_core::config::Config;
+use codex_core::protocol::SessionConfiguredEvent;
+use tempfile::TempDir;
+
+use crate::load_default_config_for_test;
+
+type ConfigMutator = dyn FnOnce(&mut Config);
+
+pub struct TestCodexBuilder {
+    config_mutators: Vec<Box<ConfigMutator>>,
+}
+
+impl TestCodexBuilder {
+    pub fn with_config<T>(mut self, mutator: T) -> Self
+    where
+        T: FnOnce(&mut Config) + 'static,
+    {
+        self.config_mutators.push(Box::new(mutator));
+        self
+    }
+
+    pub async fn build(&mut self, server: &wiremock::MockServer) -> anyhow::Result<TestCodex> {
+        // Build config pointing to the mock server and spawn Codex.
+        let model_provider = ModelProviderInfo {
+            base_url: Some(format!("{}/v1", server.uri())),
+            ..built_in_model_providers()["openai"].clone()
+        };
+        let home = TempDir::new()?;
+        let cwd = TempDir::new()?;
+        let mut config = load_default_config_for_test(&home);
+        config.cwd = cwd.path().to_path_buf();
+        config.model_provider = model_provider;
+        let mut mutators = vec![];
+        swap(&mut self.config_mutators, &mut mutators);
+
+        for mutator in mutators {
+            mutator(&mut config)
+        }
+        let conversation_manager = ConversationManager::with_auth(CodexAuth::from_api_key("dummy"));
+        let NewConversation {
+            conversation,
+            session_configured,
+            ..
+        } = conversation_manager.new_conversation(config).await?;
+
+        Ok(TestCodex {
+            home,
+            cwd,
+            codex: conversation,
+            session_configured,
+        })
+    }
+}
+
+pub struct TestCodex {
+    pub home: TempDir,
+    pub cwd: TempDir,
+    pub codex: Arc<CodexConversation>,
+    pub session_configured: SessionConfiguredEvent,
+}
+
+pub fn test_codex() -> TestCodexBuilder {
+    TestCodexBuilder {
+        config_mutators: vec![],
+    }
+}

codex-rs/core/tests/suite/mod.rs

@@ -15,3 +15,4 @@ mod rollout_list_find;
 mod seatbelt;
 mod stream_error_allows_next_turn;
 mod stream_no_completed;
+mod user_notification;

codex-rs/core/tests/suite/user_notification.rs

@@ -0,0 +1,73 @@
+#![cfg(not(target_os = "windows"))]
+
+use std::os::unix::fs::PermissionsExt;
+
+use codex_core::protocol::EventMsg;
+use codex_core::protocol::InputItem;
+use codex_core::protocol::Op;
+use core_test_support::non_sandbox_test;
+use core_test_support::responses;
+use core_test_support::test_codex::TestCodex;
+use core_test_support::test_codex::test_codex;
+use core_test_support::wait_for_event;
+use tempfile::TempDir;
+use wiremock::matchers::any;
+
+use responses::ev_assistant_message;
+use responses::ev_completed;
+use responses::sse;
+use responses::start_mock_server;
+use tokio::time::Duration;
+use tokio::time::sleep;
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn summarize_context_three_requests_and_instructions() -> anyhow::Result<()> {
+    non_sandbox_test!(result);
+
+    let server = start_mock_server().await;
+
+    let sse1 = sse(vec![ev_assistant_message("m1", "Done"), ev_completed("r1")]);
+
+    responses::mount_sse_once(&server, any(), sse1).await;
+
+    let notify_dir = TempDir::new()?;
+    // write a script to the notify that touches a file next to it
+    let notify_script = notify_dir.path().join("notify.sh");
+    std::fs::write(
+        &notify_script,
+        r#"#!/bin/bash
+set -e
+echo -n "${@: -1}" > $(dirname "${0}")/notify.txt"#,
+    )?;
+    std::fs::set_permissions(&notify_script, std::fs::Permissions::from_mode(0o755))?;
+
+    let notify_file = notify_dir.path().join("notify.txt");
+    let notify_script_str = notify_script.to_str().unwrap().to_string();
+
+    let TestCodex { codex, .. } = test_codex()
+        .with_config(move |cfg| cfg.notify = Some(vec![notify_script_str]))
+        .build(&server)
+        .await?;
+
+    // 1) Normal user input – should hit server once.
+    codex
+        .submit(Op::UserInput {
+            items: vec![InputItem::Text {
+                text: "hello world".into(),
+            }],
+        })
+        .await?;
+    wait_for_event(&codex, |ev| matches!(ev, EventMsg::TaskComplete(_))).await;
+
+    // We fork the notify script, so we need to wait for it to write to the file.
+    for _ in 0..100u32 {
+        if notify_file.exists() {
+            break;
+        }
+        sleep(Duration::from_millis(100)).await;
+    }
+
+    assert!(notify_file.exists());
+
+    Ok(())
+}