NETINFO_ITEMs are owned by BOARD.

Lifecylce management must go through BOARD_COMMIT (or at least
the frame's undo/redo lists).

common/widgets/net_selector.cpp

@@ -131,7 +131,7 @@ public:
         return NO_NET;
     }
 
-    void SetNetInfo( NETINFO_LIST* aNetInfoList )
+    void SetNetInfo( const NETINFO_LIST* aNetInfoList )
     {
         m_netinfoList = aNetInfoList;
         rebuildList();
@@ -233,12 +233,10 @@ public:
             BOARD*        board  = m_netinfoList->GetParent();
             NETINFO_ITEM *newnet = new NETINFO_ITEM( m_board, remainingName, 0 );
 
-            // add the new netinfo through the board's function so that
+            wxASSERT( board );
-            // board listeners get notified and things stay in sync.
+
-            if( board != nullptr )
+            if( board )
                 board->Add( newnet );
-            else
-                m_netinfoList->AppendNet( newnet );
 
             rebuildList();
 
@@ -249,12 +247,10 @@ public:
             }
             else
             {
-                // This indicates that the NETINFO_ITEM was not successfully appended
+                // This indicates that the NETINFO_ITEM was not successfully appended to the
-                // to the list for unknown reasons
+                // list for unknown reasons
-                if( board != nullptr )
+                if( board )
                     board->Remove( newnet );
-                else
-                    m_netinfoList->RemoveNet( newnet );
 
                 delete newnet;
             }
@@ -540,7 +536,7 @@ protected:
     int                          m_minPopupWidth;
     int                          m_maxPopupHeight;
 
-    NETINFO_LIST*    m_netinfoList;
+    const NETINFO_LIST*          m_netinfoList;
     wxString                     m_indeterminateLabel;
     BOARD*                       m_board;
 
@@ -609,7 +605,7 @@ void NET_SELECTOR::onKeyDown( wxKeyEvent& aEvt )
 }
 
 
-void NET_SELECTOR::SetNetInfo( NETINFO_LIST* aNetInfoList )
+void NET_SELECTOR::SetNetInfo( const NETINFO_LIST* aNetInfoList )
 {
     m_netSelectorPopup->SetNetInfo( aNetInfoList );
 }

cvpcb/display_footprints_frame.cpp

@@ -465,7 +465,7 @@ void DISPLAY_FOOTPRINTS_FRAME::ReloadFootprint( FOOTPRINT* aFootprint )
         return;
 
     GetBoard()->DeleteAllFootprints();
-    GetBoard()->GetNetInfo().RemoveUnusedNets();
+    GetBoard()->RemoveUnusedNets( nullptr );
     GetCanvas()->GetView()->Clear();
 
 
@@ -504,7 +504,7 @@ void DISPLAY_FOOTPRINTS_FRAME::InitDisplay()
         return;
 
     GetBoard()->DeleteAllFootprints();
-    GetBoard()->GetNetInfo().RemoveUnusedNets();
+    GetBoard()->RemoveUnusedNets( nullptr );
     GetCanvas()->GetView()->Clear();
 
     INFOBAR_REPORTER infoReporter( m_infoBar );

eeschema/lib_item.h

@@ -199,7 +199,7 @@ public:
             return std::max( GetPenWidth(), aSettings->GetMinPenWidth() );
     }
 
-    LIB_SYMBOL* GetParent() const
+    LIB_SYMBOL* GetParent() const  // Replace EDA_ITEM::GetParent() with a more useful return-type
     {
         return (LIB_SYMBOL*) m_parent;
     }

include/widgets/net_selector.h

@@ -46,7 +46,7 @@ public:
 
     ~NET_SELECTOR() override;
 
-    void SetNetInfo( NETINFO_LIST* aNetInfoList );
+    void SetNetInfo( const NETINFO_LIST* aNetInfoList );
 
     // Set to wxEmptyString to disallow indeterminate settings
     void SetIndeterminateString( const wxString& aString );

pcbnew/board.cpp

@@ -1163,6 +1163,12 @@ BOARD_ITEM* BOARD::GetItem( const KIID& aID ) const
             return group;
     }
 
+    for( NETINFO_ITEM* netInfo : m_NetInfo )
+    {
+        if( netInfo->m_Uuid == aID )
+            return netInfo;
+    }
+
     if( m_Uuid == aID )
         return const_cast<BOARD*>( this );
 

pcbnew/board.h

@@ -805,9 +805,9 @@ public:
         return m_NetInfo;
     }
 
-    NETINFO_LIST& GetNetInfo()
+    void RemoveUnusedNets( BOARD_COMMIT* aCommit )
     {
-        return m_NetInfo;
+        m_NetInfo.RemoveUnusedNets( aCommit );
     }
 
 #ifndef SWIG

pcbnew/dialogs/dialog_copper_zones.cpp

@@ -370,7 +370,7 @@ bool DIALOG_COPPER_ZONE::TransferDataToWindow()
 
 void DIALOG_COPPER_ZONE::readNetInformation()
 {
-    NETINFO_LIST& netInfoList = m_Parent->GetBoard()->GetNetInfo();
+    const NETINFO_LIST& netInfoList = m_Parent->GetBoard()->GetNetInfo();
 
     m_netInfoItemList.clear();
     m_netInfoItemList.reserve( netInfoList.GetNetCount() );

pcbnew/dialogs/dialog_net_inspector.cpp

@@ -2112,9 +2112,9 @@ void DIALOG_NET_INSPECTOR::onRenameNet( wxCommandEvent& aEvent )
         // is easier.
         auto removed_item = m_data_model->deleteItem( m_data_model->findItem( net ) );
 
-        m_brd->GetNetInfo().RemoveNet( net );
+        m_brd->Remove( net );
         net->SetNetname( fullNetName );
-        m_brd->GetNetInfo().AppendNet( net );
+        m_brd->Add( net );
         m_frame->OnModify();
 
         if( netFilterMatches( net ) )

pcbnew/footprint_viewer_frame.cpp

@@ -1058,7 +1058,7 @@ void FOOTPRINT_VIEWER_FRAME::SelectAndViewFootprint( int aMode )
             selectionTool->ClearSelection( true /* quiet mode */ );
 
         GetBoard()->DeleteAllFootprints();
-        GetBoard()->GetNetInfo().RemoveUnusedNets();
+        GetBoard()->RemoveUnusedNets( nullptr );
 
         FOOTPRINT* footprint = PROJECT_PCB::PcbFootprintLibs( &Prj() )->FootprintLoad( getCurNickname(),
                                                                         getCurFootprintName() );

pcbnew/netinfo.h

@@ -2,7 +2,7 @@
  * This program source code file is part of KiCad, a free EDA CAD application.
  *
  * Copyright (C) 2009 Jean-Pierre Charras, jp.charras at wanadoo.fr
- * Copyright (C) 1992-2022 KiCad Developers, see AUTHORS.txt for contributors.
+ * Copyright (C) 1992-2023 KiCad Developers, see AUTHORS.txt for contributors.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
@@ -36,27 +36,16 @@
 #include <string_utils.h>
 
 
-
-class wxDC;
-class LINE_READER;
 class EDA_DRAW_FRAME;
 class PAD;
 class PCB_TRACK;
 class BOARD;
 class BOARD_ITEM;
+class BOARD_COMMIT;
 class MSG_PANEL_ITEM;
 class PCB_BASE_FRAME;
 
 
-/*****************************/
-/* flags for a RATSNEST_ITEM */
-/*****************************/
-#define CH_VISIBLE          1        /* Visible */
-#define CH_UNROUTABLE       2        /* Don't use autorouter. */
-#define CH_ROUTE_REQ        4        /* Must be routed by the autorouter. */
-#define CH_ACTIF            8        /* Not routed. */
-#define LOCAL_RATSNEST_ITEM 0x8000   /* Line between two pads of a single footprint. */
-
 DECL_VEC_FOR_SWIG( PADS_VEC, PAD* )
 DECL_VEC_FOR_SWIG( TRACKS_VEC, PCB_TRACK* )
 
@@ -175,7 +164,7 @@ public:
      */
     void Clear();
 
-    BOARD* GetParent() const
+    BOARD* GetParent() const      // Replace EDA_ITEM::GetParent() with a more useful return-type
     {
         return m_parent;
     }
@@ -360,22 +349,6 @@ public:
      */
     unsigned GetNetCount() const { return m_netNames.size(); }
 
-    /**
-     * Add \a aNewElement to the end of the net list. Negative net code means it is going to be
-     * auto-assigned.
-     */
-    void AppendNet( NETINFO_ITEM* aNewElement );
-
-    /**
-     * Remove a net from the net list.
-     */
-    void RemoveNet( NETINFO_ITEM* aNet );
-    void RemoveUnusedNets();
-
-    /**
-     * @return the number of pads in board.
-     */
-
     /// Return the name map, at least for python.
     const NETNAMES_MAP& NetsByName() const      { return  m_netNames; }
 
@@ -471,6 +444,19 @@ public:
         return m_parent;
     }
 
+protected:  // Access is through the BOARD, which is a friend class
+    /**
+     * Add \a aNewElement to the end of the net list. Negative net code means it is going to be
+     * auto-assigned.
+     */
+    void AppendNet( NETINFO_ITEM* aNewElement );
+
+    /**
+     * Remove a net from the net list.
+     */
+    void RemoveNet( NETINFO_ITEM* aNet );
+    void RemoveUnusedNets( BOARD_COMMIT* aCommit );
+
 private:
     /**
      * Delete the list of nets (and free memory).

pcbnew/netinfo_list.cpp

@@ -22,6 +22,7 @@
  */
 
 #include <board.h>
+#include <board_commit.h>
 #include <footprint.h>
 #include <macros.h>
 #include <pad.h>
@@ -113,19 +114,24 @@ void NETINFO_LIST::RemoveNet( NETINFO_ITEM* aNet )
 }
 
 
-void NETINFO_LIST::RemoveUnusedNets()
+void NETINFO_LIST::RemoveUnusedNets( BOARD_COMMIT* aCommit )
 {
     NETCODES_MAP               existingNets = m_netCodes;
+    std::vector<NETINFO_ITEM*> unusedNets;
 
     m_netCodes.clear();
     m_netNames.clear();
 
-    for( std::pair<const int, NETINFO_ITEM*> item : existingNets )
+    for( const auto& [ netCode, netInfo ] : existingNets )
     {
-        if( item.second->IsCurrent() )
+        if( netInfo->IsCurrent() )
         {
-            m_netNames.insert( std::make_pair( item.second->GetNetname(), item.second ) );
+            m_netNames.insert( std::make_pair( netInfo->GetNetname(), netInfo ) );
-            m_netCodes.insert( std::make_pair( item.first, item.second ) );
+            m_netCodes.insert( std::make_pair( netCode, netInfo ) );
+        }
+        else if( aCommit )
+        {
+            aCommit->Removed( netInfo );
         }
     }
 }

pcbnew/netlist_reader/board_netlist_updater.cpp

@@ -1239,7 +1239,7 @@ bool BOARD_NETLIST_UPDATER::UpdateNetlist( NETLIST& aNetlist )
             }
         }
 
-        m_board->GetNetInfo().RemoveUnusedNets();
+        m_board->RemoveUnusedNets( &m_commit );
 
         // When new footprints are added, the automatic zone refill is disabled because:
         // * it creates crashes when calculating dynamic ratsnests if auto refill is enabled.

pcbnew/pcbnew_config.cpp

@@ -60,7 +60,7 @@ bool PCB_EDIT_FRAME::LoadProjectSettings()
     KIGFX::RENDER_SETTINGS*        rs = GetCanvas()->GetView()->GetPainter()->GetSettings();
     KIGFX::PCB_RENDER_SETTINGS*    renderSettings = static_cast<KIGFX::PCB_RENDER_SETTINGS*>( rs );
 
-    NETINFO_LIST& nets = GetBoard()->GetNetInfo();
+    const NETINFO_LIST& nets = GetBoard()->GetNetInfo();
 
     std::set<int>& hiddenNets = renderSettings->GetHiddenNets();
     hiddenNets.clear();
@@ -154,7 +154,7 @@ void PCB_EDIT_FRAME::SaveProjectLocalSettings()
     // Save render settings that aren't stored in PCB_DISPLAY_OPTIONS
 
     std::shared_ptr<NET_SETTINGS>& netSettings = project.NetSettings();
-    NETINFO_LIST&                  nets = GetBoard()->GetNetInfo();
+    const NETINFO_LIST&            nets = GetBoard()->GetNetInfo();
     KIGFX::RENDER_SETTINGS*        rs = GetCanvas()->GetView()->GetPainter()->GetSettings();
     KIGFX::PCB_RENDER_SETTINGS*    renderSettings = static_cast<KIGFX::PCB_RENDER_SETTINGS*>( rs );
 
@@ -224,7 +224,7 @@ void PCB_EDIT_FRAME::saveProjectSettings()
     localSettings.m_AutoTrackWidth   = bds.m_UseConnectedTrackWidth;
 
     // Net display settings
-    NETINFO_LIST&               nets = GetBoard()->GetNetInfo();
+    const NETINFO_LIST&         nets = GetBoard()->GetNetInfo();
     KIGFX::RENDER_SETTINGS*     rs = GetCanvas()->GetView()->GetPainter()->GetSettings();
     KIGFX::PCB_RENDER_SETTINGS* renderSettings = static_cast<KIGFX::PCB_RENDER_SETTINGS*>( rs );
 

pcbnew/specctra_import_export/specctra_export.cpp

@@ -1449,7 +1449,7 @@ void SPECCTRA_DB::FromBOARD( BOARD* aBoard )
         PIN_REF             empty( m_pcb->m_network );
         std::string         componentId;
         int                 highestNetCode = 0;
-        NETINFO_LIST& netInfo = aBoard->GetNetInfo();
+        const NETINFO_LIST& netInfo = aBoard->GetNetInfo();
 
         // find the highest numbered netCode within the board.
         for( NETINFO_LIST::iterator i = netInfo.begin(); i != netInfo.end(); ++i )

pcbnew/tools/drawing_tool.cpp

@@ -2947,11 +2947,11 @@ int DRAWING_TOOL::DrawVia( const TOOL_EVENT& aEvent )
         int selectPossibleNetsByPopMenu( std::list<int>& aNetcodeList )
         {
             ACTION_MENU         menu( true );
-            NETINFO_LIST& netInfo = m_board->GetNetInfo();
+            const NETINFO_LIST& netInfo = m_board->GetNetInfo();
             std::map<int, int>  menuIDNetCodeMap;
             int                 menuID = 1;
 
-            for( auto& netcode : aNetcodeList )
+            for( int netcode : aNetcodeList )
             {   
                 wxString menuText;
                 if( menuID < 10 )

qa/tests/pcbnew/test_libeval_compiler.cpp

@@ -153,7 +153,7 @@ BOOST_AUTO_TEST_CASE( IntrospectedProperties )
 
     BOARD brd;
 
-    NETINFO_LIST& netInfo = brd.GetNetInfo();
+    const NETINFO_LIST& netInfo = brd.GetNetInfo();
 
     std::shared_ptr<NETCLASS> netclass1( new NETCLASS( "HV" ) );
     std::shared_ptr<NETCLASS> netclass2( new NETCLASS( "otherClass" ) );