fix(tests): cover hook event dispatch paths

crates/hooks/src/lib.rs

@@ -168,3 +168,129 @@ impl HookDispatcher {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::sync::Mutex;
+    use std::time::{SystemTime, UNIX_EPOCH};
+
+    #[test]
+    fn hook_event_serializes_with_snake_case_type_and_payload() {
+        let event = HookEvent::ToolLifecycle {
+            response_id: "resp-1".to_string(),
+            tool_name: "shell".to_string(),
+            phase: "end".to_string(),
+            payload: json!({ "exit_code": 0 }),
+        };
+
+        let encoded = event.to_json();
+
+        assert_eq!(encoded["type"], "tool_lifecycle");
+        assert_eq!(encoded["response_id"], "resp-1");
+        assert_eq!(encoded["tool_name"], "shell");
+        assert_eq!(encoded["phase"], "end");
+        assert_eq!(encoded["payload"]["exit_code"], 0);
+    }
+
+    #[tokio::test]
+    async fn jsonl_sink_creates_parent_dir_and_appends_events() {
+        let root = unique_temp_dir("jsonl_sink");
+        let path = root.join("nested").join("hooks.jsonl");
+        let sink = JsonlHookSink::new(path.clone());
+
+        sink.emit(&HookEvent::ResponseStart {
+            response_id: "resp-1".to_string(),
+        })
+        .await
+        .unwrap();
+        sink.emit(&HookEvent::ResponseEnd {
+            response_id: "resp-1".to_string(),
+        })
+        .await
+        .unwrap();
+
+        let raw = std::fs::read_to_string(&path).unwrap();
+        let lines = raw.lines().collect::<Vec<_>>();
+        assert_eq!(lines.len(), 2);
+
+        let first: Value = serde_json::from_str(lines[0]).unwrap();
+        let second: Value = serde_json::from_str(lines[1]).unwrap();
+        assert!(first["at"].as_str().is_some());
+        assert_eq!(first["event"]["type"], "response_start");
+        assert_eq!(first["event"]["response_id"], "resp-1");
+        assert_eq!(second["event"]["type"], "response_end");
+        assert_eq!(second["event"]["response_id"], "resp-1");
+
+        let _ = std::fs::remove_dir_all(root);
+    }
+
+    #[tokio::test]
+    async fn dispatcher_continues_after_sink_error() {
+        let mut dispatcher = HookDispatcher::default();
+        let first = Arc::new(RecordingSink::default());
+        let second = Arc::new(RecordingSink::default());
+
+        dispatcher.add_sink(first.clone());
+        dispatcher.add_sink(Arc::new(FailingSink));
+        dispatcher.add_sink(second.clone());
+
+        dispatcher
+            .emit(HookEvent::ApprovalLifecycle {
+                approval_id: "approval-1".to_string(),
+                phase: "requested".to_string(),
+                reason: Some("needs review".to_string()),
+            })
+            .await;
+
+        assert_eq!(
+            first.events(),
+            vec![json!({
+                "type": "approval_lifecycle",
+                "approval_id": "approval-1",
+                "phase": "requested",
+                "reason": "needs review",
+            })]
+        );
+        assert_eq!(second.events(), first.events());
+    }
+
+    #[derive(Default)]
+    struct RecordingSink {
+        events: Mutex<Vec<Value>>,
+    }
+
+    impl RecordingSink {
+        fn events(&self) -> Vec<Value> {
+            self.events.lock().unwrap().clone()
+        }
+    }
+
+    #[async_trait::async_trait]
+    impl HookSink for RecordingSink {
+        async fn emit(&self, event: &HookEvent) -> Result<()> {
+            self.events.lock().unwrap().push(event.to_json());
+            Ok(())
+        }
+    }
+
+    struct FailingSink;
+
+    #[async_trait::async_trait]
+    impl HookSink for FailingSink {
+        async fn emit(&self, _event: &HookEvent) -> Result<()> {
+            anyhow::bail!("sink failed")
+        }
+    }
+
+    fn unique_temp_dir(label: &str) -> PathBuf {
+        let nanos = SystemTime::now()
+            .duration_since(UNIX_EPOCH)
+            .unwrap()
+            .as_nanos();
+        std::env::temp_dir().join(format!(
+            "deepseek-hooks-{label}-{}-{nanos}",
+            std::process::id()
+        ))
+    }
+}