undo_redo.cpp

Go to the documentation of this file.

/*
 * This program source code file is part of KiCad, a free EDA CAD application.
 *
 * Copyright (C) 2012 Jean-Pierre Charras, [email protected]
 * Copyright (C) 2012 SoftPLC Corporation, Dick Hollenbeck <[email protected]>
 * Copyright (C) 2016 CERN
 * Copyright The KiCad Developers, see AUTHORS.txt for contributors.
 * @author Maciej Suminski <[email protected]>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, you may find one here:
 * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
 * or you may search the http://www.gnu.org website for the version 2 license,
 * or you may write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
 */
 
#include <functional>
using namespace std::placeholders;
#include <macros.h>
#include <pcb_edit_frame.h>
#include <pcb_track.h>
#include <pcb_group.h>
#include <pcb_shape.h>
#include <pcb_generator.h>
#include <footprint.h>
#include <lset.h>
#include <pad.h>
#include <origin_viewitem.h>
#include <connectivity/connectivity_data.h>
#include <tool/tool_manager.h>
#include <tool/actions.h>
#include <tools/pcb_actions.h>
#include <tools/pcb_selection_tool.h>
#include <tools/pcb_control.h>
#include <tools/board_editor_control.h>
#include <board_commit.h>
#include <drawing_sheet/ds_proxy_undo_item.h>
#include <wx/msgdlg.h>
#include <pcb_board_outline.h>
 
/* Functions to undo and redo edit commands.
 *  commands to undo are stored in CurrentScreen->m_UndoList
 *  commands to redo are stored in CurrentScreen->m_RedoList
 *
 *  m_UndoList and m_RedoList handle a std::vector of PICKED_ITEMS_LIST
 *  Each PICKED_ITEMS_LIST handle a std::vector of pickers (class ITEM_PICKER),
 *  that store the list of schematic items that are concerned by the command to undo or redo
 *  and is created for each command to undo (handle also a command to redo).
 *  each picker has a pointer pointing to an item to undo or redo (in fact: deleted, added or
 *  modified),
 * and has a pointer to a copy of this item, when this item has been modified
 * (the old values of parameters are therefore saved)
 *
 *  there are 3 cases:
 *  - delete item(s) command
 *  - change item(s) command
 *  - add item(s) command
 *
 *  Undo command
 *  - delete item(s) command:
 *       =>  deleted items are moved in undo list
 *
 *  - change item(s) command
 *      => A copy of item(s) is made (a DrawPickedStruct list of wrappers)
 *      the .m_Link member of each wrapper points the modified item.
 *      the .m_Item member of each wrapper points the old copy of this item.
 *
 *  - add item(s) command
 *      =>A list of item(s) is made. The .m_Item member of each wrapper points the new item.
 *
 *  Redo command
 *  - delete item(s) old command:
 *      => deleted items are moved in EEDrawList list, and in
 *
 *  - change item(s) command
 *      => the copy of item(s) is moved in Undo list
 *
 *  - add item(s) command
 *      => The list of item(s) is used to create a deleted list in undo list(same as a delete
 *         command)
 *
 *   Some block operations that change items can be undone without memorize items, just the
 *   coordinates of the transform:
 *      move list of items (undo/redo is made by moving with the opposite move vector)
 *      mirror (Y) and flip list of items (undo/redo is made by mirror or flip items)
 *      so they are handled specifically.
 *
 */
 
 
void PCB_BASE_EDIT_FRAME::saveCopyInUndoList( PICKED_ITEMS_LIST* commandToUndo,
                                              const PICKED_ITEMS_LIST& aItemsList,
                                              UNDO_REDO aCommandType )
{
    int preExisting = (int) commandToUndo->GetCount();
 
    for( unsigned ii = 0; ii < aItemsList.GetCount(); ii++ )
        commandToUndo->PushItem( aItemsList.GetItemWrapper(ii) );
 
    for( unsigned ii = preExisting; ii < commandToUndo->GetCount(); ii++ )
    {
        EDA_ITEM* item    = commandToUndo->GetPickedItem( ii );
        UNDO_REDO command = commandToUndo->GetPickedItemStatus( ii );
 
        if( command == UNDO_REDO::UNSPECIFIED )
        {
            command = aCommandType;
            commandToUndo->SetPickedItemStatus( command, ii );
        }
 
        wxASSERT( item );
 
        switch( command )
        {
        case UNDO_REDO::CHANGED:
        case UNDO_REDO::DRILLORIGIN:
        case UNDO_REDO::GRIDORIGIN:
            // If we don't yet have a copy in the link, set one up
            if( !commandToUndo->GetPickedItemLink( ii ) )
                commandToUndo->SetPickedItemLink( BOARD_COMMIT::MakeImage( item ), ii );
 
            break;
 
        case UNDO_REDO::NEWITEM:
        case UNDO_REDO::DELETED:
        case UNDO_REDO::PAGESETTINGS:
            break;
 
        default:
            wxFAIL_MSG( wxString::Format( wxT( "Unrecognized undo command: %X" ), command ) );
            break;
        }
    }
 
    if( commandToUndo->GetCount() )
    {
        /* Save the copy in undo list */
        PushCommandToUndoList( commandToUndo );
 
        /* Clear redo list, because after a new command one cannot redo a command */
        ClearUndoORRedoList( REDO_LIST );
    }
    else
    {
        // Should not occur
        wxASSERT( false );
        delete commandToUndo;
    }
}
 
 
void PCB_BASE_EDIT_FRAME::SaveCopyInUndoList( EDA_ITEM* aItem, UNDO_REDO aCommandType )
{
    PICKED_ITEMS_LIST* commandToUndo = new PICKED_ITEMS_LIST();
    PICKED_ITEMS_LIST  itemsList;
 
    itemsList.PushItem( ITEM_PICKER( nullptr, aItem, aCommandType ) );
    saveCopyInUndoList( commandToUndo, itemsList, aCommandType );
}
 
 
void PCB_BASE_EDIT_FRAME::SaveCopyInUndoList( const PICKED_ITEMS_LIST& aItemsList,
                                              UNDO_REDO aCommandType )
{
    PICKED_ITEMS_LIST* commandToUndo = new PICKED_ITEMS_LIST();
    commandToUndo->SetDescription( aItemsList.GetDescription() );
 
    saveCopyInUndoList( commandToUndo, aItemsList, aCommandType );
}
 
 
void PCB_BASE_EDIT_FRAME::AppendCopyToUndoList( const PICKED_ITEMS_LIST& aItemsList,
                                                UNDO_REDO aCommandType )
{
    PICKED_ITEMS_LIST* commandToUndo = PopCommandFromUndoList();
 
    if( !commandToUndo )
    {
        commandToUndo = new PICKED_ITEMS_LIST();
        commandToUndo->SetDescription( aItemsList.GetDescription() );
    }
 
    saveCopyInUndoList( commandToUndo, aItemsList, aCommandType );
}
 
 
void PCB_BASE_EDIT_FRAME::RestoreCopyFromUndoList( wxCommandEvent& aEvent )
{
    if( UndoRedoBlocked() )
        return;
 
    if( GetUndoCommandCount() <= 0 )
        return;
 
    // Inform tools that undo command was issued
    m_toolManager->ProcessEvent( { TC_MESSAGE, TA_UNDO_REDO_PRE, AS_GLOBAL } );
 
    // Get the old list
    PICKED_ITEMS_LIST* list = PopCommandFromUndoList();
 
    // Undo the command
    PutDataInPreviousState( list );
 
    // Put the old list in RedoList
    list->ReversePickersListOrder();
    PushCommandToRedoList( list );
 
    OnModify();
 
    m_toolManager->ProcessEvent( { TC_MESSAGE, TA_UNDO_REDO_POST, AS_GLOBAL } );
    m_toolManager->PostEvent( EVENTS::SelectedItemsModified );
 
    m_pcb->UpdateBoardOutline();
    GetCanvas()->GetView()->Update( m_pcb->BoardOutline() );
    GetCanvas()->Refresh();
}
 
 
void PCB_BASE_EDIT_FRAME::RestoreCopyFromRedoList( wxCommandEvent& aEvent )
{
    if( UndoRedoBlocked() )
        return;
 
    if( GetRedoCommandCount() == 0 )
        return;
 
    // Inform tools that redo command was issued
    m_toolManager->ProcessEvent( EVENTS::UndoRedoPreEvent );
 
    // Get the old list
    PICKED_ITEMS_LIST* list = PopCommandFromRedoList();
 
    // Redo the command
    PutDataInPreviousState( list );
 
    // Put the old list in UndoList
    list->ReversePickersListOrder();
    PushCommandToUndoList( list );
 
    OnModify();
 
    m_toolManager->ProcessEvent( EVENTS::UndoRedoPostEvent );
    m_toolManager->PostEvent( EVENTS::SelectedItemsModified );
 
    m_pcb->UpdateBoardOutline();
    GetCanvas()->GetView()->Update( m_pcb->BoardOutline() );
    GetCanvas()->Refresh();
}
 
 
void PCB_BASE_EDIT_FRAME::PutDataInPreviousState( PICKED_ITEMS_LIST* aList )
{
    bool not_found = false;
    bool reBuild_ratsnest = false;
    bool deep_reBuild_ratsnest = false;  // true later if pointers must be rebuilt
    bool solder_mask_dirty = false;
    bool current_show_ratsnest = GetPcbNewSettings()->m_Display.m_ShowGlobalRatsnest;
    std::vector<BOX2I> dirty_rule_areas;
 
    KIGFX::PCB_VIEW* view = GetCanvas()->GetView();
    std::shared_ptr<CONNECTIVITY_DATA> connectivity = GetBoard()->GetConnectivity();
 
    GetBoard()->IncrementTimeStamp();   // clear caches
 
    // Enum to track the modification type of items. Used to enable bulk BOARD_LISTENER
    // callbacks at the end of the undo / redo operation
    enum ITEM_CHANGE_TYPE
    {
        ADDED,
        DELETED,
        CHANGED
    };
 
    std::unordered_map<EDA_ITEM*, ITEM_CHANGE_TYPE> item_changes;
 
    auto clear_local_ratsnest_flags =
            [&]( EDA_ITEM* item )
            {
                switch( item->Type() )
                {
                case PCB_TRACE_T:
                case PCB_ARC_T:
                case PCB_VIA_T:
                    static_cast<PCB_TRACK*>( item )->SetLocalRatsnestVisible( current_show_ratsnest );
                    break;
 
                case PCB_ZONE_T:
                    static_cast<ZONE*>( item )->SetLocalRatsnestVisible( current_show_ratsnest );
                    break;
 
                case PCB_FOOTPRINT_T:
                    for( PAD* pad : static_cast<FOOTPRINT*>( item )->Pads() )
                        pad->SetLocalRatsnestVisible( current_show_ratsnest );
 
                    break;
 
                default:
                    break;
                }
            };
 
    auto update_item_change_state =
            [&]( EDA_ITEM* item, ITEM_CHANGE_TYPE change_type )
            {
                auto item_itr = item_changes.find( item );
 
                if( item_itr == item_changes.end() )
                {
                    // First time we've seen this item - tag the current change type
                    item_changes.insert( { item, change_type } );
                    return;
                }
 
                // Update the item state based on the current and next change type
                switch( item_itr->second )
                {
                case ITEM_CHANGE_TYPE::ADDED:
                {
                    if( change_type == ITEM_CHANGE_TYPE::DELETED )
                    {
                        // The item was previously added, now deleted - as far as bulk callbacks
                        // are concerned, the item has never existed
                        item_changes.erase( item_itr );
                    }
                    else if( change_type == ITEM_CHANGE_TYPE::ADDED )
                    {
                        // Error condition - added an already added item
                        wxASSERT_MSG( false, wxT( "UndoRedo: should not add already added item" ) );
                    }
 
                    // For all other cases, the item remains as ADDED as seen by the bulk callbacks
                    break;
                }
                case ITEM_CHANGE_TYPE::DELETED:
                {
                    // This is an error condition - item has already been deleted so should not
                    // be operated on further
                    wxASSERT_MSG( false, wxT( "UndoRedo: should not alter already deleted item" ) );
                    break;
                }
                case ITEM_CHANGE_TYPE::CHANGED:
                {
                    if( change_type == ITEM_CHANGE_TYPE::DELETED )
                    {
                        item_itr->second = ITEM_CHANGE_TYPE::DELETED;
                    }
                    else if( change_type == ITEM_CHANGE_TYPE::ADDED )
                    {
                        // This is an error condition - item has already been changed so should not
                        // be added
                        wxASSERT_MSG( false, wxT( "UndoRedo: should not add already changed item" ) );
                    }
 
                    // Otherwise, item remains CHANGED
                    break;
                }
                }
            };
 
    // Undo in the reverse order of list creation: (this can allow stacked changes
    // like the same item can be changes and deleted in the same complex command
 
    // Restore changes in reverse order
    for( int ii = (int) aList->GetCount() - 1; ii >= 0 ; ii-- )
    {
        EDA_ITEM* eda_item = aList->GetPickedItem( (unsigned) ii );
 
        /* Test for existence of item on board.
         * It could be deleted, and no more on board:
         *   - if a call to SaveCopyInUndoList was forgotten in Pcbnew
         *   - in zones outlines, when a change in one zone merges this zone with an other
         * This test avoids a Pcbnew crash
         * Obviously, this test is not made for deleted items
         */
        UNDO_REDO status = aList->GetPickedItemStatus( ii );
 
        if( status != UNDO_REDO::DELETED
                && status != UNDO_REDO::DRILLORIGIN     // origin markers never on board
                && status != UNDO_REDO::GRIDORIGIN      // origin markers never on board
                && status != UNDO_REDO::PAGESETTINGS )  // nor are page settings proxy items
        {
            if( !GetBoard()->ResolveItem( eda_item->m_Uuid, true ) )
            {
                // Remove this non existent item
                aList->RemovePicker( ii );
                not_found = true;
 
                if( aList->GetCount() == 0 )
                    break;
 
                continue;
            }
        }
 
        // see if we must rebuild ratsnets and pointers lists
        switch( eda_item->Type() )
        {
        case PCB_FOOTPRINT_T:
            deep_reBuild_ratsnest = true;   // Pointers on pads can be invalid
            KI_FALLTHROUGH;
 
        case PCB_ZONE_T:
        case PCB_TRACE_T:
        case PCB_ARC_T:
        case PCB_VIA_T:
        case PCB_PAD_T:
            reBuild_ratsnest = true;
            break;
 
        case PCB_NETINFO_T:
            reBuild_ratsnest = true;
            deep_reBuild_ratsnest = true;
            break;
 
        default:
            break;
        }
 
        switch( eda_item->Type() )
        {
        case PCB_FOOTPRINT_T:
            solder_mask_dirty = true;
            break;
 
        case PCB_VIA_T:
            solder_mask_dirty = true;
            break;
 
        case PCB_ZONE_T:
        case PCB_TRACE_T:
        case PCB_ARC_T:
        case PCB_PAD_T:
        case PCB_SHAPE_T:
        {
            LSET layers = static_cast<BOARD_ITEM*>( eda_item )->GetLayerSet();
 
            if( layers.test( F_Mask ) || layers.test( B_Mask ) )
                solder_mask_dirty = true;
 
            break;
        }
 
        default:
            break;
        }
 
        switch( aList->GetPickedItemStatus( ii ) )
        {
        case UNDO_REDO::CHANGED:    /* Exchange old and new data for each item */
            if( eda_item->IsBOARD_ITEM() )
            {
                BOARD_ITEM*           item = static_cast<BOARD_ITEM*>( eda_item );
                BOARD_ITEM*           image = static_cast<BOARD_ITEM*>( aList->GetPickedItemLink( ii ) );
                BOARD_ITEM_CONTAINER* parent = GetBoard();
 
                if( item->GetParentFootprint() )
                {
                    // We need the current item and it's parent, which may be different from what
                    // was stored if we're multiple frames up the undo stack.
                    item = GetBoard()->ResolveItem( item->m_Uuid );
                    parent = item->GetParentFootprint();
                }
 
                view->Remove( item );
                parent->Remove( item );
 
                item->SwapItemData( image );
 
                clear_local_ratsnest_flags( item );
                item->ClearFlags( UR_TRANSIENT );
                image->SetFlags( UR_TRANSIENT );
 
                view->Add( item );
                view->Hide( item, false );
                parent->Add( item );
 
                if( item->Type() == PCB_ZONE_T && static_cast<ZONE*>( item )->GetIsRuleArea() )
                {
                    dirty_rule_areas.push_back( item->GetBoundingBox() );
                    dirty_rule_areas.push_back( image->GetBoundingBox() );
                }
 
                update_item_change_state( item, ITEM_CHANGE_TYPE::CHANGED );
            }
 
            break;
 
        case UNDO_REDO::NEWITEM:        /* new items are deleted */
            if( eda_item->IsBOARD_ITEM() )
            {
                aList->SetPickedItemStatus( UNDO_REDO::DELETED, ii );
                GetModel()->Remove( static_cast<BOARD_ITEM*>( eda_item ), REMOVE_MODE::BULK );
                update_item_change_state( eda_item, ITEM_CHANGE_TYPE::DELETED );
 
                if( eda_item->Type() != PCB_NETINFO_T )
                    view->Remove( eda_item );
 
                eda_item->SetFlags( UR_TRANSIENT );
 
                if( eda_item->Type() == PCB_ZONE_T && static_cast<ZONE*>( eda_item )->GetIsRuleArea() )
                    dirty_rule_areas.push_back( eda_item->GetBoundingBox() );
            }
 
            break;
 
        case UNDO_REDO::DELETED:    /* deleted items are put in List, as new items */
            if( eda_item->IsBOARD_ITEM() )
            {
                aList->SetPickedItemStatus( UNDO_REDO::NEWITEM, ii );
 
                clear_local_ratsnest_flags( eda_item );
                eda_item->ClearFlags( UR_TRANSIENT );
 
                GetModel()->Add( static_cast<BOARD_ITEM*>( eda_item ), ADD_MODE::BULK_APPEND );
                update_item_change_state( eda_item, ITEM_CHANGE_TYPE::ADDED );
 
                if( eda_item->Type() != PCB_NETINFO_T )
                    view->Add( eda_item );
 
                if( eda_item->Type() == PCB_ZONE_T && static_cast<ZONE*>( eda_item )->GetIsRuleArea() )
                    dirty_rule_areas.push_back( eda_item->GetBoundingBox() );
            }
 
            break;
 
        case UNDO_REDO::DRILLORIGIN:
        case UNDO_REDO::GRIDORIGIN:
        {
            // Warning: DRILLORIGIN and GRIDORIGIN undo/redo command create EDA_ITEMs
            // that cannot be casted to BOARD_ITEMs
            EDA_ITEM* image = aList->GetPickedItemLink( ii );
            VECTOR2D origin = image->GetPosition();
            image->SetPosition( eda_item->GetPosition() );
 
            if( aList->GetPickedItemStatus( ii ) == UNDO_REDO::DRILLORIGIN )
                BOARD_EDITOR_CONTROL::DoSetDrillOrigin( view, this, eda_item, origin );
            else
                PCB_CONTROL::DoSetGridOrigin( view, this, eda_item, origin );
 
            break;
        }
 
        case UNDO_REDO::PAGESETTINGS:
            if( eda_item->Type() == WS_PROXY_UNDO_ITEM_T || eda_item->Type() == WS_PROXY_UNDO_ITEM_PLUS_T )
            {
                // swap current settings with stored settings
                DS_PROXY_UNDO_ITEM  alt_item( this );
                DS_PROXY_UNDO_ITEM* item = static_cast<DS_PROXY_UNDO_ITEM*>( eda_item );
                item->Restore( this );
                *item = std::move( alt_item );
            }
 
            break;
 
        default:
            wxFAIL_MSG( wxString::Format( wxT( "PutDataInPreviousState() error (unknown code %X)" ),
                                          aList->GetPickedItemStatus( ii ) ) );
            break;
        }
 
        if( eda_item->Type() == PCB_FOOTPRINT_T )
        {
            FOOTPRINT* fp = static_cast<FOOTPRINT*>( eda_item );
            fp->InvalidateComponentClassCache();
            m_pcb->GetComponentClassManager().RebuildRequiredCaches( fp );
        }
    }
 
    if( not_found )
        wxMessageBox( _( "Incomplete undo/redo operation: some items not found" ) );
 
    // We have now swapped all the group parent and group member pointers.  But it is a
    // risky proposition to bet on the pointers being invariant, so validate them all.
    for( int ii = 0; ii < (int) aList->GetCount(); ++ii )
    {
        ITEM_PICKER& wrapper = aList->GetItemWrapper( ii );
 
        if( wrapper.GetStatus() == UNDO_REDO::DELETED )
            continue;
 
        BOARD_ITEM* parentGroup = GetBoard()->ResolveItem( wrapper.GetGroupId(), true );
        wrapper.GetItem()->SetParentGroup( dynamic_cast<PCB_GROUP*>( parentGroup ) );
 
        if( EDA_GROUP* group = dynamic_cast<PCB_GROUP*>( wrapper.GetItem() ) )
        {
            // Items list may contain dodgy pointers, so don't use RemoveAll()
            group->GetItems().clear();
 
            for( const KIID& member : wrapper.GetGroupMembers() )
            {
                if( BOARD_ITEM* memberItem = GetBoard()->ResolveItem( member, true ) )
                    group->AddItem( memberItem );
            }
        }
 
        // And prepare for a redo by updating group info based on current image
        if( EDA_ITEM* item = wrapper.GetLink() )
            wrapper.SetLink( item );
    }
 
    if( IsType( FRAME_PCB_EDITOR ) )
    {
        if( !dirty_rule_areas.empty() && (   GetPcbNewSettings()->m_Display.m_TrackClearance == SHOW_WITH_VIA_ALWAYS
                                          || GetPcbNewSettings()->m_Display.m_PadClearance ) )
        {
            view->UpdateCollidingItems( dirty_rule_areas, { PCB_TRACE_T, PCB_ARC_T, PCB_VIA_T, PCB_PAD_T } );
        }
 
        if( reBuild_ratsnest || deep_reBuild_ratsnest )
        {
            // Connectivity may have changed; rebuild internal caches to remove stale items
            GetBoard()->BuildConnectivity();
            Compile_Ratsnest( false );
        }
 
        if( solder_mask_dirty )
            HideSolderMask();
    }
 
    GetBoard()->GetComponentClassManager().InvalidateComponentClasses();
 
    PCB_SELECTION_TOOL* selTool = m_toolManager->GetTool<PCB_SELECTION_TOOL>();
    selTool->RebuildSelection();
 
    GetBoard()->SanitizeNetcodes();
 
    // Invoke bulk BOARD_LISTENER callbacks
    std::vector<BOARD_ITEM*> added_items, deleted_items, changed_items;
 
    for( auto& [item, changeType] : item_changes )
    {
        switch( changeType )
        {
        case ITEM_CHANGE_TYPE::ADDED:
            added_items.push_back( static_cast<BOARD_ITEM*>( item ) );
            break;
 
        case ITEM_CHANGE_TYPE::DELETED:
            deleted_items.push_back( static_cast<BOARD_ITEM*>( item ) );
            break;
 
        case ITEM_CHANGE_TYPE::CHANGED:
            changed_items.push_back( static_cast<BOARD_ITEM*>( item ) );
            break;
        }
    }
 
    GetToolManager()->PostAction( PCB_ACTIONS::rehatchShapes );
 
    if( added_items.size() > 0 || deleted_items.size() > 0 || changed_items.size() > 0 )
        GetBoard()->OnItemsCompositeUpdate( added_items, deleted_items, changed_items );
}
 
 
void PCB_BASE_EDIT_FRAME::ClearUndoORRedoList( UNDO_REDO_LIST whichList, int aItemCount )
{
    if( aItemCount == 0 )
        return;
 
    UNDO_REDO_CONTAINER& list = ( whichList == UNDO_LIST ) ? m_undoList : m_redoList;
 
    if( aItemCount < 0 )
    {
        list.ClearCommandList();
    }
    else
    {
        for( int ii = 0; ii < aItemCount; ii++ )
        {
            if( list.m_CommandsList.size() == 0 )
                break;
 
            PICKED_ITEMS_LIST* curr_cmd = list.m_CommandsList[0];
            list.m_CommandsList.erase( list.m_CommandsList.begin() );
            ClearListAndDeleteItems( curr_cmd );
            delete curr_cmd;    // Delete command
        }
    }
}
 
 
void PCB_BASE_EDIT_FRAME::ClearListAndDeleteItems( PICKED_ITEMS_LIST* aList )
{
    aList->ClearListAndDeleteItems(
            []( EDA_ITEM* item )
            {
                wxASSERT_MSG( item->HasFlag( UR_TRANSIENT ),
                              "Item on undo/redo list not owned by undo/redo!" );
 
                delete item;
            } );
}
 
 
void PCB_BASE_EDIT_FRAME::RollbackFromUndo()
{
    PICKED_ITEMS_LIST* undo = PopCommandFromUndoList();
    PutDataInPreviousState( undo );
    ClearListAndDeleteItems( undo );
    delete undo;
 
    m_pcb->UpdateBoardOutline();
    GetCanvas()->GetView()->Update( m_pcb->BoardOutline() );
    GetCanvas()->Refresh();
}