Scripts: the read after a script left the folder asks for a frame when it ends

When File › Scripts runs a listed script that is no longer in the Scripts folder, the folder is read again on a thread. That read now has the window's context, so it asks for a frame when it ends and an idle window takes in the new listing (and the macOS menu bar follows it) without waiting for the next input event.

crates/ui-egui/src/scripts_menu.rs

@@ -246,7 +246,8 @@ pub fn readable(p: &Value) -> bool {
 pub fn run(app: &mut VectorcraftApp, p: &Value) -> Result<Value, String> {
     let path = p.get("path").and_then(Value::as_str).ok_or("missing `path`")?;
     let source = app.session.installed_script(path).map_err(|e| {
-        refresh(app, None);
+        let ctx = app.ui_ctx.clone();
+        refresh(app, ctx.as_ref());
         e.to_string()
     })?;
     app.run("script.run", json!({"source": source, "name": vectorcraft_engine::cmd::fileio::file_name(path)}))

crates/ui-egui/src/tests/scripts_menu.rs

@@ -200,6 +200,28 @@ fn a_script_that_left_the_folder_is_not_run_and_the_folder_is_read_again() {
     let _ = std::fs::remove_dir_all(dir);
 }
 
+#[test]
+fn the_read_after_a_script_that_left_the_folder_asks_for_a_frame() {
+    let dir = folder("gone-frame");
+    let mut app = app(&dir);
+    let gone = write(&dir, "gone.js", DRAW);
+    read(&app);
+    std::fs::remove_file(&gone).unwrap();
+    let ctx = egui::Context::default();
+    let (tx, frames) = std::sync::mpsc::channel();
+    ctx.set_request_repaint_callback(move |_| {
+        let _ = tx.send(());
+    });
+    app.ui_ctx = Some(ctx);
+    assert!(menus::run_ui_command(&mut app, scripts_menu::COMMAND, &json!({ "path": gone })).unwrap().is_err());
+    // With the app's copy of the context dropped, only the read's thread can still ask for a
+    // frame; the channel closes without one when that thread ends without asking.
+    app.ui_ctx = None;
+    assert_eq!(frames.recv(), Ok(()), "the finished read asks for a frame so an idle window takes it in");
+    scripts_menu::wait();
+    let _ = std::fs::remove_dir_all(dir);
+}
+
 #[test]
 fn the_menu_notes_a_listing_that_stopped_and_a_folder_it_cannot_read() {
     let dir = folder("notes");