Add missing fullscreen check

Fixes crash when a window in a column requests to be unfullscreened.

src/layout/mod.rs

@@ -2625,6 +2625,11 @@ mod tests {
         },
         CloseWindow(#[proptest(strategy = "1..=5usize")] usize),
         FullscreenWindow(#[proptest(strategy = "1..=5usize")] usize),
+        SetFullscreenWindow {
+            #[proptest(strategy = "1..=5usize")]
+            window: usize,
+            is_fullscreen: bool,
+        },
         FocusColumnLeft,
         FocusColumnRight,
         FocusColumnFirst,
@@ -2913,6 +2918,12 @@ mod tests {
                 Op::FullscreenWindow(id) => {
                     layout.toggle_fullscreen(&id);
                 }
+                Op::SetFullscreenWindow {
+                    window,
+                    is_fullscreen,
+                } => {
+                    layout.set_fullscreen(&window, is_fullscreen);
+                }
                 Op::FocusColumnLeft => layout.focus_left(),
                 Op::FocusColumnRight => layout.focus_right(),
                 Op::FocusColumnFirst => layout.focus_column_first(),
@@ -3288,6 +3299,22 @@ mod tests {
             Op::FullscreenWindow(1),
             Op::FullscreenWindow(2),
             Op::FullscreenWindow(3),
+            Op::SetFullscreenWindow {
+                window: 1,
+                is_fullscreen: false,
+            },
+            Op::SetFullscreenWindow {
+                window: 1,
+                is_fullscreen: true,
+            },
+            Op::SetFullscreenWindow {
+                window: 2,
+                is_fullscreen: false,
+            },
+            Op::SetFullscreenWindow {
+                window: 2,
+                is_fullscreen: true,
+            },
             Op::FocusColumnLeft,
             Op::FocusColumnRight,
             Op::FocusWindowUp,
@@ -3662,6 +3689,30 @@ mod tests {
         check_ops(&ops);
     }
 
+    #[test]
+    fn unfullscreen_window_in_column() {
+        let ops = [
+            Op::AddOutput(1),
+            Op::AddWindow {
+                id: 1,
+                bbox: Rectangle::from_loc_and_size((0, 0), (100, 200)),
+                min_max_size: (Size::from((0, 0)), Size::from((i32::MAX, i32::MAX))),
+            },
+            Op::AddWindow {
+                id: 2,
+                bbox: Rectangle::from_loc_and_size((0, 0), (100, 200)),
+                min_max_size: (Size::from((0, 0)), Size::from((i32::MAX, i32::MAX))),
+            },
+            Op::ConsumeOrExpelWindowLeft,
+            Op::SetFullscreenWindow {
+                window: 2,
+                is_fullscreen: false,
+            },
+        ];
+
+        check_ops(&ops);
+    }
+
     #[test]
     fn open_right_of_on_different_workspace() {
         let ops = [

src/layout/workspace.rs

@@ -2129,6 +2129,10 @@ impl<W: LayoutElement> Workspace<W> {
             .find_map(|(col_idx, col)| col.position(window).map(|tile_idx| (col_idx, tile_idx)))
             .unwrap();
 
+        if is_fullscreen == self.columns[col_idx].is_fullscreen {
+            return;
+        }
+
         if is_fullscreen
             && col_idx == self.active_column_idx
             && self.columns[col_idx].tiles.len() == 1
@@ -3221,6 +3225,10 @@ impl<W: LayoutElement> Column<W> {
     }
 
     fn set_fullscreen(&mut self, is_fullscreen: bool) {
+        if self.is_fullscreen == is_fullscreen {
+            return;
+        }
+
         assert_eq!(self.tiles.len(), 1);
         self.is_fullscreen = is_fullscreen;
         self.update_tile_sizes(false);