feat: explorer watcher

otty/Cargo.toml

@@ -22,6 +22,7 @@ thiserror = { workspace = true }
 serde = { workspace = true }
 serde_json = { workspace = true }
 shell-words = "1.1.0"
+notify = "8.2.0"
 
 [package.metadata.generate-rpm]
 maintainer = "Ilya Shvyryalkin <ilyashvy@gmail.com>"

otty/src/events/explorer.rs

@@ -52,6 +52,14 @@ fn handle_effect(app: &mut App, effect: ExplorerEffect) -> Task<AppEvent> {
                 }
             })
         },
+        ExplorerEffect::ReloadDirectoryRequested { directory } => {
+            load_directory_async(directory.clone(), move |nodes| {
+                ExplorerIntent::DirectoryReloaded {
+                    directory: directory.clone(),
+                    nodes,
+                }
+            })
+        },
         ExplorerEffect::OpenFileTerminalTab { file_path } => {
             open_file_terminal_tab(app, file_path)
         },
@@ -100,3 +108,27 @@ fn open_file_terminal_tab(app: &mut App, file_path: PathBuf) -> Task<AppEvent> {
         },
     )))
 }
+
+#[cfg(test)]
+mod tests {
+    use std::path::PathBuf;
+
+    use super::handle_effect;
+    use crate::app::App;
+    use crate::widgets::explorer::ExplorerEffect;
+
+    #[test]
+    fn given_reload_directory_requested_when_handled_then_load_task_is_emitted()
+    {
+        let (mut app, _) = App::new();
+
+        let task = handle_effect(
+            &mut app,
+            ExplorerEffect::ReloadDirectoryRequested {
+                directory: PathBuf::from("/tmp/project"),
+            },
+        );
+
+        assert_eq!(task.units(), 1);
+    }
+}

otty/src/guards.rs

@@ -96,6 +96,24 @@ pub(crate) fn context_menu_guard(event: &AppEvent) -> MenuGuard {
                 | crate::widgets::settings::SettingsIntent::SaveFailed(_),
             ),
         ) => Allow,
+        AppEvent::Explorer(
+            crate::widgets::explorer::ExplorerEvent::Effect(_),
+        )
+        | AppEvent::Explorer(
+            crate::widgets::explorer::ExplorerEvent::Intent(
+                crate::widgets::explorer::ExplorerIntent::RootLoaded { .. }
+                | crate::widgets::explorer::ExplorerIntent::FolderLoaded {
+                    ..
+                }
+                | crate::widgets::explorer::ExplorerIntent::DirectoryChanged {
+                    ..
+                }
+                | crate::widgets::explorer::ExplorerIntent::DirectoryReloaded {
+                    ..
+                }
+                | crate::widgets::explorer::ExplorerIntent::LoadFailed { .. },
+            ),
+        ) => Allow,
         AppEvent::Explorer(
             crate::widgets::explorer::ExplorerEvent::Intent(
                 crate::widgets::explorer::ExplorerIntent::SyncRoot { .. },
@@ -178,8 +196,22 @@ pub(crate) fn inline_edit_guard(event: &AppEvent) -> bool {
             ),
         ) => false,
         AppEvent::Explorer(
+            crate::widgets::explorer::ExplorerEvent::Effect(_),
+        )
+        | AppEvent::Explorer(
             crate::widgets::explorer::ExplorerEvent::Intent(
-                crate::widgets::explorer::ExplorerIntent::SyncRoot { .. },
+                crate::widgets::explorer::ExplorerIntent::SyncRoot { .. }
+                | crate::widgets::explorer::ExplorerIntent::RootLoaded { .. }
+                | crate::widgets::explorer::ExplorerIntent::FolderLoaded {
+                    ..
+                }
+                | crate::widgets::explorer::ExplorerIntent::DirectoryChanged {
+                    ..
+                }
+                | crate::widgets::explorer::ExplorerIntent::DirectoryReloaded {
+                    ..
+                }
+                | crate::widgets::explorer::ExplorerIntent::LoadFailed { .. },
             ),
         ) => false,
         AppEvent::SyncTerminalGridSizes => false,
@@ -193,8 +225,11 @@ pub(crate) fn inline_edit_guard(event: &AppEvent) -> bool {
 
 #[cfg(test)]
 mod tests {
+    use std::path::PathBuf;
+
     use super::{MenuGuard, context_menu_guard, inline_edit_guard};
     use crate::events::AppEvent;
+    use crate::widgets::explorer::{ExplorerEvent, ExplorerIntent};
     use crate::widgets::sidebar::{SidebarEvent, SidebarIntent};
 
     #[test]
@@ -211,4 +246,28 @@ mod tests {
      {
         assert!(!inline_edit_guard(&AppEvent::SyncTerminalGridSizes));
     }
+
+    #[test]
+    fn given_explorer_directory_change_when_context_menu_guard_runs_then_event_is_allowed()
+     {
+        let guard = context_menu_guard(&AppEvent::Explorer(
+            ExplorerEvent::Intent(ExplorerIntent::DirectoryChanged {
+                directory: PathBuf::from("/tmp/project"),
+            }),
+        ));
+
+        assert!(matches!(guard, MenuGuard::Allow));
+    }
+
+    #[test]
+    fn given_explorer_directory_change_when_inline_edit_guard_runs_then_edit_is_not_cancelled()
+     {
+        let event = AppEvent::Explorer(ExplorerEvent::Intent(
+            ExplorerIntent::DirectoryChanged {
+                directory: PathBuf::from("/tmp/project"),
+            },
+        ));
+
+        assert!(!inline_edit_guard(&event));
+    }
 }

otty/src/subscription.rs

@@ -26,6 +26,8 @@ pub(super) fn subscription(app: &App) -> Subscription<AppEvent> {
         }
     }
 
+    subs.push(app.widgets.explorer.subscription().map(AppEvent::Explorer));
+
     // Quick launch tick for launch indicators and auto-persist
     if app.widgets.quick_launch.has_active_launches()
         || app.widgets.quick_launch.state_is_dirty()

otty/src/widgets/explorer/event.rs

@@ -18,6 +18,13 @@ pub(crate) enum ExplorerIntent {
         path: TreePath,
         nodes: Vec<FileNode>,
     },
+    /// A watched directory emitted a filesystem tree change.
+    DirectoryChanged { directory: PathBuf },
+    /// Watched directory contents reloaded successfully.
+    DirectoryReloaded {
+        directory: PathBuf,
+        nodes: Vec<FileNode>,
+    },
     /// A directory load operation failed.
     LoadFailed { message: String },
 }
@@ -29,6 +36,8 @@ pub(crate) enum ExplorerEffect {
     LoadRootRequested { root: PathBuf },
     /// Request asynchronous loading of a folder's children.
     LoadFolderRequested { path: TreePath, directory: PathBuf },
+    /// Request asynchronous reloading of a watched directory.
+    ReloadDirectoryRequested { directory: PathBuf },
     /// Request opening a file in a command terminal tab.
     OpenFileTerminalTab { file_path: PathBuf },
 }

otty/src/widgets/explorer/mod.rs

@@ -6,9 +6,10 @@ pub(crate) mod services;
 pub(crate) mod state;
 pub(crate) mod types;
 pub(crate) mod view;
+mod watcher;
 
 pub(crate) use event::{ExplorerEffect, ExplorerEvent, ExplorerIntent};
-use iced::Task;
+use iced::{Subscription, Task};
 pub(crate) use reducer::ExplorerCtx;
 use state::ExplorerState;
 
@@ -36,6 +37,11 @@ impl ExplorerWidget {
         reducer::reduce(&mut self.state, event, ctx)
     }
 
+    /// Return active filesystem watcher subscription for loaded directories.
+    pub(crate) fn subscription(&self) -> Subscription<ExplorerEvent> {
+        watcher::subscription(self.state.watched_directories())
+    }
+
     /// Return a tree view model for the sidebar panel.
     pub(crate) fn vm(&self) -> model::ExplorerTreeViewModel<'_> {
         model::ExplorerTreeViewModel {
@@ -72,3 +78,36 @@ impl ExplorerWidget {
         &self.state
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use std::path::PathBuf;
+
+    use super::{ExplorerCtx, ExplorerIntent, ExplorerWidget};
+
+    #[test]
+    fn given_empty_explorer_when_subscription_requested_then_no_units_are_registered()
+     {
+        let widget = ExplorerWidget::new();
+
+        assert_eq!(widget.subscription().units(), 0);
+    }
+
+    #[test]
+    fn given_rooted_explorer_when_subscription_requested_then_watcher_unit_is_registered()
+     {
+        let mut widget = ExplorerWidget::new();
+        let ctx = ExplorerCtx {
+            active_shell_cwd: None,
+        };
+
+        let _task = widget.reduce(
+            ExplorerIntent::SyncRoot {
+                cwd: PathBuf::from("/tmp/project"),
+            },
+            &ctx,
+        );
+
+        assert_eq!(widget.subscription().units(), 1);
+    }
+}