Less repeatedly spawning item groups when checking consistency (#72064)

* Less repeatedly spawning item groups when checking consistency

* Further tweaks

src/item_factory.cpp

@@ -2482,7 +2482,7 @@ void Item_factory::check_definitions() const
         }
     }
     for( const auto &elem : m_template_groups ) {
-        elem.second->check_consistency();
+        elem.second->check_consistency( true );
         inp_mngr.pump_events();
     }
 }

src/item_group.cpp

@@ -46,17 +46,19 @@ item Item_spawn_data::create_single( const time_point &birthday ) const
     return create_single( birthday, rec );
 }
 
-void Item_spawn_data::check_consistency() const
+void Item_spawn_data::check_consistency( bool actually_spawn ) const
 {
     if( on_overflow != overflow_behaviour::none && !container_item ) {
         debugmsg( "item group %s specifies overflow behaviour but not container", context() );
     }
     // Spawn ourselves with all possible items being definitely spawned, so as
     // to verify e.g. that if a container item was specified it can actually
     // contain what was wanted.
-    ItemList dummy_list;
-    dummy_list.reserve( 20 );
-    create( dummy_list, calendar::turn_zero, spawn_flags::maximized );
+    if( actually_spawn ) {
+        ItemList dummy_list;
+        dummy_list.reserve( 20 );
+        create( dummy_list, calendar::turn_zero, spawn_flags::maximized );
+    }
 }
 
 void Item_spawn_data::relic_generator::load( const JsonObject &jo )
@@ -376,7 +378,7 @@ void Single_item_creator::finalize( const itype_id &container_ex )
     }
 }
 
-void Single_item_creator::check_consistency() const
+void Single_item_creator::check_consistency( bool actually_spawn ) const
 {
     if( type == S_ITEM ) {
         if( !item::type_is_defined( itype_id( id ) ) ) {
@@ -394,7 +396,10 @@ void Single_item_creator::check_consistency() const
     if( modifier ) {
         modifier->check_consistency( context() );
     }
-    Item_spawn_data::check_consistency();
+    // If this is to create a group and there's no container to restrain it, no need to actually create it,
+    // since groups are processed separately.
+    Item_spawn_data::check_consistency( ( type == S_ITEM_GROUP &&
+                                          !container_item ) ? false : actually_spawn );
 }
 
 bool Single_item_creator::remove_item( const itype_id &itemid )
@@ -713,10 +718,10 @@ void Item_modifier::modify( item &new_item, const std::string &context ) const
 void Item_modifier::check_consistency( const std::string &context ) const
 {
     if( ammo != nullptr ) {
-        ammo->check_consistency();
+        ammo->check_consistency( true );
     }
     if( container != nullptr ) {
-        container->check_consistency();
+        container->check_consistency( true );
     }
     if( with_ammo < 0 || with_ammo > 100 ) {
         debugmsg( "in %s: Item modifier's ammo chance %d is out of range", context, with_ammo );
@@ -886,12 +891,16 @@ item Item_group::create_single( const time_point &birthday, RecursionList &rec )
     return item( null_item_id, birthday );
 }
 
-void Item_group::check_consistency() const
+void Item_group::check_consistency( bool actually_spawn ) const
 {
+    // if type is collection, then spawning itself automatically spawnes all entries,
+    // thus no need to spawn them individually.
     for( const auto &elem : items ) {
-        elem->check_consistency();
+        // Assuming every entry needs to be spawned.
+        elem->check_consistency( true );
     }
-    Item_spawn_data::check_consistency();
+    // If this group has no container, no need to spawn it as a whole as every entry has been spawned.
+    Item_spawn_data::check_consistency( container_item ? actually_spawn : false );
 }
 
 int Item_spawn_data::get_probability( bool skip_event_check ) const

src/item_group.h

@@ -166,7 +166,7 @@ class Item_spawn_data
          * Check item / spawn settings for consistency. Includes
          * checking for valid item types and valid settings.
          */
-        virtual void check_consistency() const;
+        virtual void check_consistency( bool actually_spawn ) const;
         /**
          * For item blacklisted, remove the given item from this and
          * all linked groups.
@@ -334,7 +334,7 @@ class Single_item_creator : public Item_spawn_data
         void finalize( const itype_id &container = itype_id::NULL_ID() ) override;
         item create_single( const time_point &birthday, RecursionList &rec ) const override;
         item create_single_without_container( const time_point &birthday, RecursionList &rec ) const;
-        void check_consistency() const override;
+        void check_consistency( bool actually_spawn ) const override;
         bool remove_item( const itype_id &itemid ) override;
         void replace_items( const std::unordered_map<itype_id, itype_id> &replacements ) override;
 
@@ -383,7 +383,7 @@ class Item_group : public Item_spawn_data
         std::size_t create( ItemList &list, const time_point &birthday, RecursionList &rec,
                             spawn_flags ) const override;
         item create_single( const time_point &birthday, RecursionList &rec ) const override;
-        void check_consistency() const override;
+        void check_consistency( bool actually_spawn ) const override;
         bool remove_item( const itype_id &itemid ) override;
         void replace_items( const std::unordered_map<itype_id, itype_id> &replacements ) override;
         bool has_item( const itype_id &itemid ) const override;