fix: fix toggle to previous tab when deleting tabs

zellij-server/src/screen.rs

@@ -270,6 +270,7 @@ impl Screen {
     /// Closes this [`Screen`]'s active [`Tab`], exiting the application if it happens
     /// to be the last tab.
     pub fn close_tab(&mut self) {
+        let future_previous = self.previous_active_tab_index;
         let active_tab_index = self.active_tab_index.unwrap();
         if self.tabs.len() > 1 {
             self.switch_tab_prev();
@@ -300,6 +301,7 @@ impl Screen {
             }
             self.update_tabs();
         }
+        self.previous_active_tab_index = future_previous;
     }
 
     pub fn resize_to_screen(&mut self, new_screen_size: PositionAndSize) {
@@ -338,6 +340,14 @@ impl Screen {
         }
     }
 
+    /// Returns an immutable reference to this [`Screen`]'s previous active [`Tab`].
+    pub fn get_previous_tab(&self) -> Option<&Tab> {
+        match self.previous_active_tab_index {
+            Some(tab) => self.tabs.get(&tab),
+            None => None,
+        }
+    }
+
     /// Returns a mutable reference to this [`Screen`]'s active [`Tab`].
     pub fn get_active_tab_mut(&mut self) -> Option<&mut Tab> {
         match self.active_tab_index {
@@ -427,10 +437,11 @@ impl Screen {
             self.switch_tab_next();
         }
     }
-    pub fn go_to_last_tab(&mut self) {
+    pub fn toggle_tab(&mut self) {
         let active_tab_index = self.active_tab_index.unwrap();
-        if let Some(i) = self.previous_active_tab_index {
-            self.go_to_tab(i + 1);
+        if let Some(_) = self.previous_active_tab_index {
+            let position = self.get_previous_tab().unwrap().position;
+            self.go_to_tab(position + 1);
         }
         self.previous_active_tab_index = Some(active_tab_index);
         self.update_tabs();
@@ -771,7 +782,7 @@ pub(crate) fn screen_thread_main(
                 break;
             }
             ScreenInstruction::ToggleTab => {
-                screen.go_to_last_tab();
+                screen.toggle_tab();
                 screen
                     .bus
                     .senders

zellij-server/src/unit/screen_tests.rs

@@ -249,7 +249,7 @@ fn move_focus_right_at_right_screen_edge_changes_tab() {
 }
 
 #[test]
-pub fn switch_to_last_tab() {
+pub fn toggle_to_previous_tab_simple() {
     let position_and_size = PositionAndSize {
         cols: 121,
         rows: 20,
@@ -264,17 +264,111 @@ pub fn switch_to_last_tab() {
     screen.go_to_tab(1);
     screen.go_to_tab(2);
 
-    screen.go_to_last_tab();
+    screen.toggle_tab();
     assert_eq!(
         screen.get_active_tab().unwrap().position,
         0,
-        "Active tab switched to last tab"
+        "Active tab toggler to previous tab"
     );
 
-    screen.go_to_last_tab();
+    screen.toggle_tab();
     assert_eq!(
         screen.get_active_tab().unwrap().position,
         1,
-        "Active tab switched to last tab"
+        "Active tab toggler to previous tab"
+    );
+}
+
+#[test]
+pub fn toggle_to_previous_tab_create_tabs_only() {
+    let position_and_size = PositionAndSize {
+        cols: 121,
+        rows: 20,
+        x: 0,
+        y: 0,
+        ..Default::default()
+    };
+    let mut screen = create_new_screen(position_and_size);
+
+    screen.new_tab(1);
+    screen.new_tab(2);
+    screen.new_tab(3);
+
+    screen.toggle_tab();
+    assert_eq!(
+        screen.get_active_tab().unwrap().position,
+        1,
+        "Active tab toggler to previous tab"
+    );
+
+    screen.toggle_tab();
+    assert_eq!(
+        screen.get_active_tab().unwrap().position,
+        2,
+        "Active tab toggler to previous tab"
+    );
+
+    screen.toggle_tab();
+    assert_eq!(
+        screen.get_active_tab().unwrap().position,
+        1,
+        "Active tab toggler to previous tab"
+    );
+}
+
+#[test]
+pub fn toggle_to_previous_tab_delete() {
+    let position_and_size = PositionAndSize {
+        cols: 121,
+        rows: 20,
+        x: 0,
+        y: 0,
+        ..Default::default()
+    };
+    let mut screen = create_new_screen(position_and_size);
+
+    screen.new_tab(1);
+    screen.new_tab(2);
+    screen.new_tab(3);
+
+    screen.toggle_tab();
+    assert_eq!(
+        screen.get_active_tab().unwrap().position,
+        1,
+        "Active tab toggler to previous tab"
+    );
+    assert_eq!(
+        screen.get_previous_tab().unwrap().position,
+        2,
+        "Previous active tab invalid"
+    );
+
+    screen.close_tab();
+    assert_eq!(
+        screen.get_active_tab().unwrap().position,
+        0,
+        "Active tab toggler to previous tab"
+    );
+    assert_eq!(
+        screen.get_previous_tab().unwrap().position,
+        1,
+        "Previous active tab invalid"
+    );
+    assert_eq!(
+        screen.get_previous_tab().unwrap().index,
+        2,
+        "Previous active tab invalid"
+    );
+
+    screen.toggle_tab();
+    assert_eq!(
+        screen.get_active_tab().unwrap().position,
+        1,
+        "Active tab toggler to previous tab"
+    );
+    assert_eq!(
+        screen.get_previous_tab().unwrap().position,
+        0,
+        "Previous active tab invalid"
     );
 }

zellij-utils/src/input/mod.rs

@@ -37,7 +37,7 @@ pub fn get_mode_info(
             ("x".to_string(), "Close".to_string()),
             ("r".to_string(), "Rename".to_string()),
             ("s".to_string(), "Sync".to_string()),
-            ("Tab".to_string(), "Last".to_string()),
+            ("Tab".to_string(), "Toggle".to_string()),
         ],
         InputMode::Scroll => vec![
             ("↓↑".to_string(), "Scroll".to_string()),