LibCards+Games: Return ErrorOr from CardStack::add_all_grabbed_cards()

...and CardGame::pick_up_cards_from_stack() which is its only caller.

Userland/Games/Solitaire/Game.cpp

@@ -266,7 +266,7 @@ void Game::mousedown_event(GUI::MouseEvent& event)
                     if (event.button() == GUI::MouseButton::Secondary) {
                         preview_card(to_check, click_location);
                     } else {
-                        pick_up_cards_from_stack(to_check, click_location, Cards::CardStack::MovementRule::Alternating);
+                        pick_up_cards_from_stack(to_check, click_location, Cards::CardStack::MovementRule::Alternating).release_value_but_fixme_should_propagate_errors();
                         m_mouse_down_location = click_location;
                         m_mouse_down = true;
                     }

Userland/Games/Spider/Game.cpp

@@ -272,7 +272,7 @@ void Game::mousedown_event(GUI::MouseEvent& event)
                         update(top_card.rect());
                     }
                 } else if (!is_moving_cards()) {
-                    pick_up_cards_from_stack(to_check, click_location, Cards::CardStack::MovementRule::Same);
+                    pick_up_cards_from_stack(to_check, click_location, Cards::CardStack::MovementRule::Same).release_value_but_fixme_should_propagate_errors();
                     m_mouse_down_location = click_location;
                     // When the user wants to automatically move cards, do not go into the drag mode.
                     if (event.button() != GUI::MouseButton::Secondary)

Userland/Libraries/LibCards/CardGame.cpp

@@ -52,10 +52,11 @@ Gfx::IntRect CardGame::moving_cards_bounds() const
     return m_moving_cards.first().rect().united(m_moving_cards.last().rect());
 }
 
-void CardGame::pick_up_cards_from_stack(Cards::CardStack& stack, Gfx::IntPoint click_location, CardStack::MovementRule movement_rule)
+ErrorOr<void> CardGame::pick_up_cards_from_stack(Cards::CardStack& stack, Gfx::IntPoint click_location, CardStack::MovementRule movement_rule)
 {
-    stack.add_all_grabbed_cards(click_location, m_moving_cards, movement_rule);
+    TRY(stack.add_all_grabbed_cards(click_location, m_moving_cards, movement_rule));
     m_moving_cards_source_stack = stack;
+    return {};
 }
 
 RefPtr<CardStack> CardGame::find_stack_to_drop_on(CardStack::MovementRule movement_rule) const

Userland/Libraries/LibCards/CardGame.h

@@ -42,7 +42,7 @@ public:
     NonnullRefPtrVector<Card> const& moving_cards() const { return m_moving_cards; }
     Gfx::IntRect moving_cards_bounds() const;
     RefPtr<CardStack> moving_cards_source_stack() const { return m_moving_cards_source_stack; }
-    void pick_up_cards_from_stack(CardStack&, Gfx::IntPoint click_location, CardStack::MovementRule);
+    ErrorOr<void> pick_up_cards_from_stack(CardStack&, Gfx::IntPoint click_location, CardStack::MovementRule);
     RefPtr<CardStack> find_stack_to_drop_on(CardStack::MovementRule) const;
     ErrorOr<void> drop_cards_on_stack(CardStack&, CardStack::MovementRule);
     void clear_moving_cards();

Userland/Libraries/LibCards/CardStack.cpp

@@ -121,7 +121,7 @@ void CardStack::rebound_cards()
         card.set_position(m_stack_positions.at(card_index++));
 }
 
-void CardStack::add_all_grabbed_cards(Gfx::IntPoint click_location, NonnullRefPtrVector<Card>& grabbed, MovementRule movement_rule)
+ErrorOr<void> CardStack::add_all_grabbed_cards(Gfx::IntPoint click_location, NonnullRefPtrVector<Card>& grabbed, MovementRule movement_rule)
 {
     VERIFY(grabbed.is_empty());
 
@@ -129,9 +129,9 @@ void CardStack::add_all_grabbed_cards(Gfx::IntPoint click_location, NonnullRefPt
         auto& top_card = peek();
         if (top_card.rect().contains(click_location)) {
             top_card.set_moving(true);
-            grabbed.append(top_card);
+            TRY(grabbed.try_append(top_card));
         }
-        return;
+        return {};
     }
 
     RefPtr<Card> last_intersect;
@@ -144,22 +144,22 @@ void CardStack::add_all_grabbed_cards(Gfx::IntPoint click_location, NonnullRefPt
             last_intersect = card;
         } else if (!last_intersect.is_null()) {
             if (grabbed.is_empty()) {
-                grabbed.append(*last_intersect);
+                TRY(grabbed.try_append(*last_intersect));
                 last_intersect->set_moving(true);
             }
 
             if (card.is_upside_down()) {
                 grabbed.clear();
-                return;
+                return {};
             }
 
             card.set_moving(true);
-            grabbed.append(card);
+            TRY(grabbed.try_append(card));
         }
     }
 
     if (grabbed.is_empty() && !last_intersect.is_null()) {
-        grabbed.append(*last_intersect);
+        TRY(grabbed.try_append(*last_intersect));
         last_intersect->set_moving(true);
     }
 
@@ -198,6 +198,8 @@ void CardStack::add_all_grabbed_cards(Gfx::IntPoint click_location, NonnullRefPt
         }
         grabbed.clear();
     }
+
+    return {};
 }
 
 bool CardStack::is_allowed_to_push(Card const& card, size_t stack_size, MovementRule movement_rule) const

Userland/Libraries/LibCards/CardStack.h

@@ -49,7 +49,7 @@ public:
     void rebound_cards();
 
     bool is_allowed_to_push(Card const&, size_t stack_size = 1, MovementRule movement_rule = MovementRule::Alternating) const;
-    void add_all_grabbed_cards(Gfx::IntPoint click_location, NonnullRefPtrVector<Card>& grabbed, MovementRule movement_rule = MovementRule::Alternating);
+    ErrorOr<void> add_all_grabbed_cards(Gfx::IntPoint click_location, NonnullRefPtrVector<Card>& grabbed, MovementRule movement_rule = MovementRule::Alternating);
 
     bool preview_card(Gfx::IntPoint click_location);
     void clear_card_preview();