Bugfix: MTP watcher misses external files

vdavid · vdavid · commit 266026d5a33f · 2026-04-07T12:23:33.000+02:00
`invalidate_listing_cache` was called with the raw `mtp://` URL from `LISTING_CACHE` (e.g., `mtp://mtp-device/65537/Documents`), but the MTP listing cache keys use `normalize_mtp_path` (e.g., `/Documents`). The key mismatch made every invalidation a no-op, so `list_directory` kept returning stale cached entries and `compute_diff` found no changes.

On macOS this was masked because FSEvents fires with enough latency that the 5s cache TTL expires before diffs are computed. On Linux, inotify fires instantly, so all diff attempts hit the still-fresh cache.
diff --git a/apps/desktop/src-tauri/src/mtp/connection/event_loop.rs b/apps/desktop/src-tauri/src/mtp/connection/event_loop.rs
@@ -11,7 +11,7 @@ use tauri::{AppHandle, Emitter};
 use tokio::sync::{Mutex, broadcast};
 
 use super::cache::EVENT_DEBOUNCE_MS;
-use super::{MtpConnectionManager, connection_manager};
+use super::{MtpConnectionManager, connection_manager, normalize_mtp_path};
 use crate::file_system::listing::{get_listings_by_volume_prefix, update_listing_entries};
 use crate::file_system::{DirectoryDiff, FileEntry, compute_diff};
 use std::path::PathBuf;
@@ -243,10 +243,12 @@ impl MtpConnectionManager {
                 mtp_path.strip_prefix('/').unwrap_or(&mtp_path).to_string()
             };
 
-            // Invalidate the MTP listing cache before re-reading so we get fresh data
-            // (otherwise we'd compare stale cached data with itself and detect no changes)
+            // Invalidate the MTP listing cache before re-reading so we get fresh data.
+            // Must use the normalized MTP path (e.g., "/Documents") — not the raw LISTING_CACHE
+            // path (e.g., "mtp://mtp-device/65537/Documents") — because that's what list_directory
+            // uses as the cache key.
             connection_manager()
-                .invalidate_listing_cache(device_id, storage_id, &path)
+                .invalidate_listing_cache(device_id, storage_id, &normalize_mtp_path(&mtp_path))
                 .await;
 
             // Re-read the directory from the MTP device
