Move workspace intersection checking logic to `window_workspaces_inte…

…rsect`

src/miral/basic_window_manager.cpp

@@ -294,28 +294,16 @@ void miral::BasicWindowManager::refocus(
     // Try to activate to recently active window of any application in a shared workspace
     {
         miral::Window new_focus;
-
         auto workspaces_containing_window_mut = workspaces_containing_window;
-        // Need to sort only once
         std::sort(workspaces_containing_window_mut.begin(), workspaces_containing_window_mut.end());
 
-        mru_active_windows.enumerate([&](miral::Window& other_window)
+        mru_active_windows.enumerate(
+            [&](miral::Window& other_window)
             {
-                if(!info_for(other_window).is_visible()) return true;
-
-                auto workspaces_containing_other_window = workspaces_containing(other_window);
-                std::sort(workspaces_containing_other_window.begin(), workspaces_containing_other_window.end());
-
-                auto intersection = std::vector<std::shared_ptr<Workspace>>();
+                if (!info_for(other_window).is_visible())
+                    return true;
 
-                std::set_intersection(
-                    workspaces_containing_window_mut.begin(),
-                    workspaces_containing_window_mut.end(),
-                    workspaces_containing_other_window.begin(),
-                    workspaces_containing_other_window.end(),
-                    std::back_inserter(intersection));
-
-                if(!intersection.empty())
+                if (window_workspaces_intersect(workspaces_containing_window_mut, other_window))
                     return !(new_focus = select_active_window(other_window));
 
                 return true;
@@ -2999,3 +2987,20 @@ void miral::BasicWindowManager::move_cursor_to(mir::geometry::PointF point)
         });
     });
 }
+
+auto miral::BasicWindowManager::window_workspaces_intersect(std::vector<std::shared_ptr<Workspace>> const& w1_workspaces, Window const& w2) const -> bool
+{
+    auto w2_workspaces = workspaces_containing(w2);
+    std::sort(w2_workspaces.begin(), w2_workspaces.end());
+
+    auto intersection = std::vector<std::shared_ptr<Workspace>>();
+
+    std::set_intersection(
+        w1_workspaces.begin(),
+        w1_workspaces.end(),
+        w2_workspaces.begin(),
+        w2_workspaces.end(),
+        std::back_inserter(intersection));
+
+    return !intersection.empty();
+}

src/miral/basic_window_manager.h

@@ -332,6 +332,10 @@ class BasicWindowManager : public virtual mir::shell::WindowManager,
     void for_each_descendent_in(WindowInfo const& info, std::function<void(const Window&)> func);
     /// Gathers windows provided WindowInfo
     auto collect_windows(WindowInfo const& info) -> SurfaceSet;
+
+    // w1_workspaces must be sorted
+    auto window_workspaces_intersect(
+        std::vector<std::shared_ptr<Workspace>> const& w1_workspaces, Window const& w2) const -> bool;
 };
 }