feat(window-state): support using a custom filename (#1138)

* feat(window-state): support using a custom filename

ref: https://github.com/tauri-apps/plugins-workspace/pull/1079

* generate api

* fmt

.changes/window-state-custom-filename.md

@@ -0,0 +1,6 @@
+---
+"window-state": "patch"
+"window-state-js": "patch"
+---
+
+Add `Builder::with_filename` to support using a custom filename. Also add `AppHandleExt::file_name` and a similar function in JS, to retrieve it later.

.changes/window-state-default-filename.md

@@ -0,0 +1,5 @@
+---
+"window-state": "patch"
+---
+
+**Breaking change**: Renamed `STATE_FILENAME` const to `DEFAULT_FILENAME`.

plugins/window-state/guest-js/index.ts

@@ -38,5 +38,11 @@ async function restoreState(
 async function restoreStateCurrent(flags: StateFlags): Promise<void> {
   return restoreState(getCurrent().label, flags);
 }
+/**
+ *  Get the name of the file used to store window state.
+ */
+async function filename(): Promise<string> {
+  return invoke("plugin:window-state|filename");
+}
 
-export { restoreState, restoreStateCurrent, saveWindowState };
+export { restoreState, restoreStateCurrent, saveWindowState, filename };

plugins/window-state/src/cmd.rs

@@ -32,3 +32,8 @@ pub async fn restore_state<R: Runtime>(
         .map_err(|e| e.to_string())?;
     Ok(())
 }
+
+#[command]
+pub fn filename<R: Runtime>(app: AppHandle<R>) -> String {
+    app.filename()
+}

plugins/window-state/src/lib.rs

@@ -28,7 +28,10 @@ use std::{
 
 mod cmd;
 
-pub const STATE_FILENAME: &str = ".window-state.json";
+/// Default filename used to store window state.
+///
+/// If using a custom filename, you should probably use [`AppHandleExt::filename`] instead.
+pub const DEFAULT_FILENAME: &str = ".window-state.json";
 
 #[derive(Debug, thiserror::Error)]
 pub enum Error {
@@ -60,6 +63,10 @@ impl Default for StateFlags {
     }
 }
 
+struct PluginState {
+    filename: String,
+}
+
 #[derive(Debug, Deserialize, Serialize, PartialEq)]
 struct WindowState {
     width: f64,
@@ -98,12 +105,15 @@ struct WindowStateCache(Arc<Mutex<HashMap<String, WindowState>>>);
 pub trait AppHandleExt {
     /// Saves all open windows state to disk
     fn save_window_state(&self, flags: StateFlags) -> Result<()>;
+    /// Get the name of the file used to store window state.
+    fn filename(&self) -> String;
 }
 
 impl<R: Runtime> AppHandleExt for tauri::AppHandle<R> {
     fn save_window_state(&self, flags: StateFlags) -> Result<()> {
         if let Ok(app_dir) = self.path().app_config_dir() {
-            let state_path = app_dir.join(STATE_FILENAME);
+            let plugin_state = self.state::<PluginState>();
+            let state_path = app_dir.join(&plugin_state.filename);
             let cache = self.state::<WindowStateCache>();
             let mut state = cache.0.lock().unwrap();
             for (label, s) in state.iter_mut() {
@@ -120,6 +130,10 @@ impl<R: Runtime> AppHandleExt for tauri::AppHandle<R> {
             Ok(())
         }
     }
+
+    fn filename(&self) -> String {
+        self.state::<PluginState>().filename.clone()
+    }
 }
 
 pub trait WindowExt {
@@ -286,6 +300,7 @@ pub struct Builder {
     denylist: HashSet<String>,
     skip_initial_state: HashSet<String>,
     state_flags: StateFlags,
+    filename: Option<String>,
 }
 
 impl Builder {
@@ -299,6 +314,12 @@ impl Builder {
         self
     }
 
+    /// Sets a custom filename to use when saving and restoring window states from disk.
+    pub fn with_filename(mut self, filename: impl Into<String>) -> Self {
+        self.filename.replace(filename.into());
+        self
+    }
+
     /// Sets a list of windows that shouldn't be tracked and managed by this plugin
     /// for example splash screen windows.
     pub fn with_denylist(mut self, denylist: &[&str]) -> Self {
@@ -314,15 +335,18 @@ impl Builder {
 
     pub fn build<R: Runtime>(self) -> TauriPlugin<R> {
         let flags = self.state_flags;
+        let filename = self.filename.unwrap_or_else(|| DEFAULT_FILENAME.into());
+
         PluginBuilder::new("window-state")
             .invoke_handler(tauri::generate_handler![
                 cmd::save_window_state,
-                cmd::restore_state
+                cmd::restore_state,
+                cmd::filename
             ])
             .setup(|app, _api| {
                 let cache: Arc<Mutex<HashMap<String, WindowState>>> =
                     if let Ok(app_dir) = app.path().app_config_dir() {
-                        let state_path = app_dir.join(STATE_FILENAME);
+                        let state_path = app_dir.join(&filename);
                         if state_path.exists() {
                             Arc::new(Mutex::new(
                                 std::fs::read(state_path)
@@ -339,6 +363,7 @@ impl Builder {
                         Default::default()
                     };
                 app.manage(WindowStateCache(cache));
+                app.manage(PluginState { filename });
                 Ok(())
             })
             .on_window_ready(move |window| {