feat(lock): implémentation lock inter-process app-data-dir V1 — acquisition non-bloquante avec RAII

crates/web-server/src/lib.rs

@@ -128,6 +128,13 @@ pub fn run_from_args(args: Vec<String>) -> ExitCode {
             return ExitCode::from(2);
         }
     };
+    let _app_data_lock = match backend::acquire_app_data_dir_lock(&config.app_data_dir) {
+        Ok(lock) => lock,
+        Err(err) => {
+            eprintln!("idea --serve: {}", serve_app_data_lock_message(&err));
+            return ExitCode::from(1);
+        }
+    };
 
     match tokio::runtime::Builder::new_multi_thread()
         .enable_all()
@@ -147,6 +154,19 @@ pub fn run_from_args(args: Vec<String>) -> ExitCode {
     }
 }
 
+fn serve_app_data_lock_message(err: &backend::AppDataDirLockError) -> String {
+    match err {
+        backend::AppDataDirLockError::Contended { lock_path } => format!(
+            "app-data dir is already locked at {}; another IdeA instance is using this app-data-dir",
+            lock_path.display()
+        ),
+        backend::AppDataDirLockError::Io { lock_path, source } => format!(
+            "failed to access app-data lock at {}: {source}",
+            lock_path.display()
+        ),
+    }
+}
+
 /// Configuration shared by the standalone and embedded web-server entry points.
 #[derive(Clone, Debug)]
 pub struct ServerConfig {
@@ -5036,6 +5056,31 @@ mod tests {
         }
     }
 
+    #[test]
+    fn idea_serve_lock_failure_stops_before_backend_store_writes() {
+        let app_data_dir =
+            std::env::temp_dir().join(format!("idea-server-lock-{}", Uuid::new_v4()));
+        let web_root = create_web_root();
+        let _guard = backend::acquire_app_data_dir_lock(&app_data_dir).unwrap();
+
+        let code = run_from_args(vec![
+            "--app-data-dir".to_owned(),
+            app_data_dir.to_string_lossy().into_owned(),
+            "--web-root".to_owned(),
+            web_root.to_string_lossy().into_owned(),
+        ]);
+
+        assert_eq!(code, ExitCode::from(1));
+        let mut entries = std::fs::read_dir(&app_data_dir)
+            .unwrap()
+            .map(|entry| entry.unwrap().file_name().to_string_lossy().into_owned())
+            .collect::<Vec<_>>();
+        entries.sort();
+        assert_eq!(entries, vec!["idea.lock"]);
+        let _ = std::fs::remove_dir_all(app_data_dir);
+        let _ = std::fs::remove_dir_all(web_root);
+    }
+
     #[test]
     fn default_app_data_dir_uses_tauri_identifier_with_env_precedence() {
         let _lock = ENV_LOCK.lock().unwrap();