feat(layouts): exact panes constraint (#2206)

* style(fmt): remove warnings

* fix(swap-layouts): introduce exact panes constraint

* fix(swap-layouts): improve floating pane swap layout ux

* style(fmt): rustfmt

4 files changed, 36 insertions, 28 deletions

diff --git a/zellij-server/src/pty.rs b/zellij-server/src/pty.rs
index 83255e61c..5daccd17f 100644
--- a/zellij-server/src/pty.rs
+++ b/zellij-server/src/pty.rs
@@ -467,7 +467,7 @@ impl Pty {
                         TerminalAction::RunCommand(ref mut command) => {
                             command.cwd = Some(cwd);
                         },
-                        TerminalAction::OpenFile(ref file, line_number, ref mut edit_cwd) => {
+                        TerminalAction::OpenFile(ref _file, _line_number, ref mut edit_cwd) => {
                             match edit_cwd.as_mut() {
                                 Some(edit_cwd) => {
                                     *edit_cwd = cwd.join(&edit_cwd);
diff --git a/zellij-server/src/tab/swap_layouts.rs b/zellij-server/src/tab/swap_layouts.rs
index 57085779f..942a65408 100644
--- a/zellij-server/src/tab/swap_layouts.rs
+++ b/zellij-server/src/tab/swap_layouts.rs
@@ -40,12 +40,14 @@ impl SwapLayouts {
         let mut base_swap_floating_layout = BTreeMap::new();
         let tiled_panes_count = layout.0.pane_count();
         let floating_panes_count = layout.1.len();
-        // we set MaxPanes to the current panes in the layout, because the base layout is not
+        // we set ExactPanes to the current panes in the layout, because the base layout is not
         // intended to be progressive - i.e. to have additional panes added to it
+        // we also don't want it to be applied for less than the expected amount of panes, because
+        // then unintended things can happen
         // we still want to keep it around in case we'd like to swap layouts without adding panes
-        base_swap_tiled_layout.insert(LayoutConstraint::MaxPanes(tiled_panes_count), layout.0);
+        base_swap_tiled_layout.insert(LayoutConstraint::ExactPanes(tiled_panes_count), layout.0);
         base_swap_floating_layout
-            .insert(LayoutConstraint::MaxPanes(floating_panes_count), layout.1);
+            .insert(LayoutConstraint::ExactPanes(floating_panes_count), layout.1);
         self.swap_tiled_layouts
             .insert(0, (base_swap_tiled_layout, Some("BASE".into())));
         self.swap_floating_layouts
@@ -174,6 +176,9 @@ impl SwapLayouts {
             LayoutConstraint::MinPanes(min_panes) => {
                 tiled_panes.visible_panes_count() >= *min_panes
             },
+            LayoutConstraint::ExactPanes(pane_count) => {
+                tiled_panes.visible_panes_count() == *pane_count
+            },
             LayoutConstraint::NoConstraint => true,
         }
     }
@@ -189,6 +194,9 @@ impl SwapLayouts {
             LayoutConstraint::MinPanes(min_panes) => {
                 floating_panes.visible_panes_count() >= *min_panes
             },
+            LayoutConstraint::ExactPanes(pane_count) => {
+                floating_panes.visible_panes_count() == *pane_count
+            },
             LayoutConstraint::NoConstraint => true,
         }
     }
diff --git a/zellij-server/src/tab/unit/snapshots/zellij_server__tab__tab_integration_tests__when_closing_a_pane_in_auto_layout_the_focus_goes_to_last_focused_pane.snap b/zellij-server/src/tab/unit/snapshots/zellij_server__tab__tab_integration_tests__when_closing_a_pane_in_auto_layout_the_focus_goes_to_last_focused_pane.snap
index 8f548b1dc..48fb7d0cd 100644
--- a/zellij-server/src/tab/unit/snapshots/zellij_server__tab__tab_integration_tests__when_closing_a_pane_in_auto_layout_the_focus_goes_to_last_focused_pane.snap
+++ b/zellij-server/src/tab/unit/snapshots/zellij_server__tab__tab_integration_tests__when_closing_a_pane_in_auto_layout_the_focus_goes_to_last_focused_pane.snap
@@ -1,26 +1,26 @@
 ---
 source: zellij-server/src/tab/./unit/tab_integration_tests.rs
-assertion_line: 5333
+assertion_line: 5700
 expression: snapshot
 ---
-00 (C): ┌ Pane #1 ──────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
-01 (C): │                                                                                                                       │
-02 (C): │                                                                                                                       │
-03 (C): │                                                                                                                       │
-04 (C): │                                                                                                                       │
-05 (C): │                                                                                                                       │
-06 (C): │                                                                                                                       │
-07 (C): │                                                                                                                       │
-08 (C): │                                                                                                                       │
-09 (C): └───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
-10 (C): ┌ Pane #2 ──────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
-11 (C): │                                                                                                                       │
-12 (C): │                                                                                                                       │
-13 (C): │                                                                                                                       │
-14 (C): │                                                                                                                       │
-15 (C): │                                                                                                                       │
-16 (C): │                                                                                                                       │
-17 (C): │                                                                                                                       │
-18 (C): │                                                                                                                       │
-19 (C): └───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
+00 (C): ┌ Pane #1 ──────────────────────────────────────────────────┐┌ Pane #2 ─────────────────────────────────────────────────┐
+01 (C): │                                                           ││                                                          │
+02 (C): │                                                           ││                                                          │
+03 (C): │                                                           ││                                                          │
+04 (C): │                                                           ││                                                          │
+05 (C): │                                                           ││                                                          │
+06 (C): │                                                           ││                                                          │
+07 (C): │                                                           ││                                                          │
+08 (C): │                                                           ││                                                          │
+09 (C): │                                                           ││                                                          │
+10 (C): │                                                           ││                                                          │
+11 (C): │                                                           ││                                                          │
+12 (C): │                                                           ││                                                          │
+13 (C): │                                                           ││                                                          │
+14 (C): │                                                           ││                                                          │
+15 (C): │                                                           ││                                                          │
+16 (C): │                                                           ││                                                          │
+17 (C): │                                                           ││                                                          │
+18 (C): │                                                           ││                                                          │
+19 (C): └───────────────────────────────────────────────────────────┘└──────────────────────────────────────────────────────────┘
 
diff --git a/zellij-server/src/tab/unit/tab_integration_tests.rs b/zellij-server/src/tab/unit/tab_integration_tests.rs
index 45b3defdf..11de1c298 100644
--- a/zellij-server/src/tab/unit/tab_integration_tests.rs
+++ b/zellij-server/src/tab/unit/tab_integration_tests.rs
@@ -5681,8 +5681,8 @@ fn when_closing_a_pane_in_auto_layout_the_focus_goes_to_last_focused_pane() {
         )),
         true,
     );
-    tab.move_focus_down(client_id);
-    tab.move_focus_down(client_id);
+    let _ = tab.move_focus_down(client_id);
+    let _ = tab.move_focus_down(client_id);
     tab.close_pane(PaneId::Terminal(3), false, Some(client_id));
     tab.render(&mut output, None).unwrap();
 
@@ -5694,7 +5694,7 @@ fn when_closing_a_pane_in_auto_layout_the_focus_goes_to_last_focused_pane() {
     );
     assert_eq!(
         cursor_coordinates,
-        Some((1, 11)),
+        Some((62, 1)),
         "cursor coordinates moved to the new pane",
     );
     assert_snapshot!(snapshot);