feat: disable Cut and Copy buttons when no text is selected (#588)

- [x] I have disclosed use of any AI generated code in my commit
messages.
- If you are using an LLM, and do not fully understand the changes it is
making to the code base, do not create a PR.
- In our experience, AI generated code often results in overly complex
code that lacks enough context for a proper fix or feature inclusion.
This results in considerably longer code reviews. Due to this, AI
authored or partially authored PRs may be closed without comment.
- [x] I understand these changes in full and will be able to respond to
review comments.
- [x] My change is accurately described in the commit message.
- [x] My contribution is tested and working as described.
- [x] I have read the [Developer Certificate of
Origin](https://developercertificate.org/) and certify my contribution
under its conditions.

src/main.rs

@@ -194,6 +194,7 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
 #[derive(Clone, Copy, Debug, Deserialize, Eq, Hash, Ord, PartialEq, PartialOrd, Serialize)]
 pub enum Action {
     Todo,
+    NoOp,
     About,
     CloseFile,
     CloseProject(usize),
@@ -244,6 +245,7 @@ impl Action {
     fn message(&self, entity_opt: Option<Entity>) -> Message {
         match self {
             Self::Todo => Message::Todo,
+            Self::NoOp => Message::NoOp,
             Self::About => Message::ToggleContextPage(ContextPage::About),
             Self::CloseFile => Message::CloseFile,
             Self::CloseProject(project_i) => Message::CloseProject(*project_i),
@@ -371,6 +373,7 @@ pub enum Message {
     Modifiers(Modifiers),
     NewFile,
     NewWindow,
+    NoOp,
     NotifyEvent(notify::Event),
     NotifyWatcher(WatcherWrapper),
     OpenFile(PathBuf),
@@ -2161,6 +2164,9 @@ impl Application for App {
                     }
                 }
             }
+            Message::NoOp => {
+                // Do nothing
+            }
             Message::NotifyEvent(event) => {
                 // Reload tabs that changed
                 let mut tab_reload = Vec::new();
@@ -3027,12 +3033,19 @@ impl Application for App {
     }
 
     fn header_start(&self) -> Vec<Element<'_, Message>> {
+        let has_selection = match self.active_tab() {
+            Some(Tab::Editor(tab)) => tab.editor.lock().unwrap().selection() != Selection::None,
+            Some(Tab::GitDiff(_)) => false,
+            None => false,
+        };
+
         vec![menu_bar(
             &self.core,
             &self.config,
             &self.config_state,
             &self.key_binds,
             &self.projects,
+            has_selection,
         )]
     }
 
@@ -3088,9 +3101,10 @@ impl Application for App {
                     text_box = text_box.line_numbers();
                 }
                 let mut popover = widget::popover(text_box);
+                let has_selection = tab.editor.lock().unwrap().selection() != Selection::None;
                 if let Some(point) = tab.context_menu {
                     popover = popover
-                        .popup(menu::context_menu(&self.key_binds, tab_id))
+                        .popup(menu::context_menu(&self.key_binds, tab_id, has_selection))
                         .position(widget::popover::Position::Point(point));
                 }
                 tab_column = tab_column.push(popover);

src/menu.rs

@@ -119,6 +119,7 @@ fn format_recent_menu_path(path: &PathBuf, home_dir_opt: Option<&PathBuf>) -> St
 pub fn context_menu<'a>(
     key_binds: &HashMap<KeyBind, Action>,
     entity: segmented_button::Entity,
+    has_selection: bool,
 ) -> Element<'a, Message> {
     fn key_style(theme: &cosmic::Theme) -> TextStyle {
         // TODO use wayland popups
@@ -130,7 +131,7 @@ pub fn context_menu<'a>(
         }
     }
 
-    let menu_item = |menu_label, menu_action| {
+    let base_menu_item = |menu_label, menu_action| {
         let mut key = String::new();
         for (key_bind, key_action) in key_binds.iter() {
             if key_action == &menu_action {
@@ -145,6 +146,18 @@ pub fn context_menu<'a>(
                 .class(theme::Text::Custom(key_style))
                 .into(),
         ])
+    };
+
+    let optional_menu_item = |menu_label, menu_action, disabled| {
+        base_menu_item(menu_label, menu_action).on_press_maybe(if disabled {
+            None
+        } else {
+            Some(Message::TabContextAction(entity, menu_action))
+        })
+    };
+
+    let menu_item = |menu_label, menu_action| {
+        base_menu_item(menu_label, menu_action)
             .on_press(Message::TabContextAction(entity, menu_action))
     };
 
@@ -153,8 +166,8 @@ pub fn context_menu<'a>(
             menu_item(fl!("undo"), Action::Undo).into(),
             menu_item(fl!("redo"), Action::Redo).into(),
             divider::horizontal::light().into(),
-            menu_item(fl!("cut"), Action::Cut).into(),
-            menu_item(fl!("copy"), Action::Copy).into(),
+            optional_menu_item(fl!("cut"), Action::Cut, !has_selection).into(),
+            optional_menu_item(fl!("copy"), Action::Copy, !has_selection).into(),
             menu_item(fl!("paste"), Action::Paste).into(),
             menu_item(fl!("select-all"), Action::SelectAll).into(),
         ]),
@@ -186,6 +199,7 @@ pub fn menu_bar<'a>(
     config_state: &ConfigState,
     key_binds: &HashMap<KeyBind, Action>,
     projects: &Vec<(String, PathBuf)>,
+    has_selection: bool,
 ) -> Element<'a, Message> {
     //TODO: port to libcosmic
     let menu_tab_width = |tab_width: u16| {
@@ -278,8 +292,16 @@ pub fn menu_bar<'a>(
                         MenuItem::Button(fl!("undo"), None, Action::Undo),
                         MenuItem::Button(fl!("redo"), None, Action::Redo),
                         MenuItem::Divider,
-                        MenuItem::Button(fl!("cut"), None, Action::Cut),
-                        MenuItem::Button(fl!("copy"), None, Action::Copy),
+                        if has_selection {
+                            MenuItem::Button(fl!("cut"), None, Action::Cut)
+                        } else {
+                            MenuItem::ButtonDisabled(fl!("cut"), None, Action::NoOp)
+                        },
+                        if has_selection {
+                            MenuItem::Button(fl!("copy"), None, Action::Copy)
+                        } else {
+                            MenuItem::ButtonDisabled(fl!("copy"), None, Action::NoOp)
+                        },
                         MenuItem::Button(fl!("paste"), None, Action::Paste),
                         MenuItem::Button(fl!("select-all"), None, Action::SelectAll),
                         MenuItem::Divider,