Fixing case of no selectable applications

src/miral/application_selector.cpp

@@ -117,6 +117,7 @@ auto ApplicationSelector::next(bool reverse) -> Application
 
     // Attempt to focus the next application after the originally selected application.
     auto it = std::find(focus_list.begin(), focus_list.end(), selected);
+    auto start_it = it;
     do {
         if (reverse)
         {
@@ -137,6 +138,10 @@ auto ApplicationSelector::next(bool reverse) -> Application
                 it = focus_list.begin();
             }
         }
+
+        // We made it all the way through the list but failed to find anything.
+        if (it == start_it)
+            break;
     } while (!tools.try_select_application(*it));
 
     return *it;

tests/miral/application_selector.cpp

@@ -45,6 +45,20 @@ struct ApplicationSelectorTest : mt::TestWindowManagerTools
         return window;
     }
 
+    auto create_unfocusable_window() -> Window
+    {
+        mir::shell::SurfaceSpecification creation_parameters;
+        creation_parameters.type = mir_window_type_normal;
+        creation_parameters.focus_mode = MirFocusMode::mir_focus_mode_disabled;
+        creation_parameters.set_size({600, 400});
+        auto window = create_and_select_window(creation_parameters);
+
+        // Simulates a new application opening and gaining focus
+        application_selector.advise_new_app(window.application());
+        application_selector.advise_focus_gained(window_manager_tools.info_for(window));
+        return window;
+    }
+
     auto create_window_list(int num_windows) -> std::vector<Window>
     {
         std::vector<Window> window_list;
@@ -126,4 +140,4 @@ TEST_F(ApplicationSelectorTest, deleting_selected_app_makes_the_next_app_selecte
     application_selector.advise_delete_app(windows[1].application());
     auto application = application_selector.get_focused();
     EXPECT_TRUE(application == windows[0].application());
-}
+}