Add error message support to task undo

src/app.rs

@@ -674,15 +674,19 @@ impl App {
             );
     }
 
-    pub fn task_undo(&self) {
+    pub fn task_undo(&self) -> Result<(), String> {
         if self.tasks.len() == 0 {
-            return
+            return Ok(());
         }
         let output = Command::new("task")
             .arg("rc.confirmation=off")
             .arg("undo")
-            .output()
-            .expect("Cannot run `task undo`. Check documentation for more information");
+            .output();
+
+        match output {
+            Ok(_) => Ok(()),
+            Err(_) => Err("Cannot run `task undo`. Check documentation for more information".to_string()),
+        }
     }
 
     pub fn task_edit(&self) {

src/main.rs

@@ -69,7 +69,13 @@ fn main() -> Result<(), Box<dyn Error>> {
                                     app.error = e;
                                 }
                             },
-                            Key::Char('u') => app.task_undo(),
+                            Key::Char('u') => match app.task_undo() {
+                                Ok(_) => (),
+                                Err(e) => {
+                                    app.mode = AppMode::TaskError;
+                                    app.error = e;
+                                }
+                            },
                             Key::Char('e') => {
                                 events.pause_event_loop(&mut terminal);
                                 app.task_edit();