Add COMMIT structure to Schematic and Symbol editors

Provides a single-point access for modifying the schematic and symbol
elements that allows chaining updates and reverting partial changes.
Standardizes the undo hierarchy between pcb and schematic editors

As this is another layer on the existing undo/redo structure, the
initial commit does not replace all undo/redo calls currently existing.
These will be handled in a series of follow-on commits

common/commit.cpp

@@ -45,7 +45,7 @@ COMMIT::~COMMIT()
 }
 
 
-COMMIT& COMMIT::Stage( EDA_ITEM* aItem, CHANGE_TYPE aChangeType )
+COMMIT& COMMIT::Stage( EDA_ITEM* aItem, CHANGE_TYPE aChangeType, BASE_SCREEN* aScreen )
 {
     // CHT_MODIFY and CHT_DONE are not compatible
     wxASSERT( ( aChangeType & ( CHT_MODIFY | CHT_DONE ) ) != ( CHT_MODIFY | CHT_DONE ) );
@@ -56,11 +56,11 @@ COMMIT& COMMIT::Stage( EDA_ITEM* aItem, CHANGE_TYPE aChangeType )
     {
     case CHT_ADD:
         wxASSERT( m_changedItems.find( aItem ) == m_changedItems.end() );
-        makeEntry( aItem, CHT_ADD | flag );
+        makeEntry( aItem, CHT_ADD | flag, nullptr, aScreen );
         return *this;
 
     case CHT_REMOVE:
-        makeEntry( aItem, CHT_REMOVE | flag );
+        makeEntry( aItem, CHT_REMOVE | flag, nullptr, aScreen );
         return *this;
 
     case CHT_MODIFY:
@@ -71,7 +71,7 @@ COMMIT& COMMIT::Stage( EDA_ITEM* aItem, CHANGE_TYPE aChangeType )
         wxASSERT( clone );
 
         if( clone )
-            return createModified( parent, clone, flag );
+            return createModified( parent, clone, flag, aScreen );
 
         break;
     }
@@ -84,16 +84,17 @@ COMMIT& COMMIT::Stage( EDA_ITEM* aItem, CHANGE_TYPE aChangeType )
 }
 
 
-COMMIT& COMMIT::Stage( std::vector<EDA_ITEM*>& container, CHANGE_TYPE aChangeType )
+COMMIT& COMMIT::Stage( std::vector<EDA_ITEM*> &container, CHANGE_TYPE aChangeType,
+        BASE_SCREEN *aScreen )
 {
     for( EDA_ITEM* item : container )
-        Stage( item, aChangeType );
+        Stage( item, aChangeType, aScreen);
 
     return *this;
 }
 
 
-COMMIT& COMMIT::Stage( const PICKED_ITEMS_LIST& aItems, UNDO_REDO aModFlag )
+COMMIT& COMMIT::Stage( const PICKED_ITEMS_LIST &aItems, UNDO_REDO aModFlag, BASE_SCREEN *aScreen )
 {
     for( unsigned int i = 0; i < aItems.GetCount(); i++ )
     {
@@ -108,11 +109,11 @@ COMMIT& COMMIT::Stage( const PICKED_ITEMS_LIST& aItems, UNDO_REDO aModFlag )
             assert( change_type == UNDO_REDO::CHANGED );
 
             // There was already a copy created, so use it
-            Modified( item, copy );
+            Modified( item, copy, aScreen );
         }
         else
         {
-            Stage( item, convert( change_type ) );
+            Stage( item, convert( change_type ), aScreen );
         }
     }
 
@@ -120,15 +121,15 @@ COMMIT& COMMIT::Stage( const PICKED_ITEMS_LIST& aItems, UNDO_REDO aModFlag )
 }
 
 
-int COMMIT::GetStatus( EDA_ITEM* aItem )
+int COMMIT::GetStatus( EDA_ITEM* aItem, BASE_SCREEN *aScreen )
 {
-    COMMIT_LINE* entry = findEntry( parentObject( aItem ) );
+    COMMIT_LINE* entry = findEntry( parentObject( aItem ), aScreen );
 
     return entry ? entry->m_type : 0;
 }
 
 
-COMMIT& COMMIT::createModified( EDA_ITEM* aItem, EDA_ITEM* aCopy, int aExtraFlags )
+COMMIT& COMMIT::createModified( EDA_ITEM* aItem, EDA_ITEM* aCopy, int aExtraFlags, BASE_SCREEN* aScreen )
 {
     EDA_ITEM* parent = parentObject( aItem );
     auto entryIt = m_changedItems.find( parent );
@@ -139,22 +140,22 @@ COMMIT& COMMIT::createModified( EDA_ITEM* aItem, EDA_ITEM* aCopy, int aExtraFlag
         return *this; // item has been already modified once
     }
 
-    makeEntry( parent, CHT_MODIFY | aExtraFlags, aCopy );
+    makeEntry( parent, CHT_MODIFY | aExtraFlags, aCopy, aScreen );
 
     return *this;
 }
 
 
-void COMMIT::makeEntry( EDA_ITEM* aItem, CHANGE_TYPE aType, EDA_ITEM* aCopy )
+void COMMIT::makeEntry( EDA_ITEM* aItem, CHANGE_TYPE aType, EDA_ITEM* aCopy, BASE_SCREEN *aScreen )
 {
     // Expect an item copy if it is going to be modified
     wxASSERT( !!aCopy == ( ( aType & CHT_TYPE ) == CHT_MODIFY ) );
 
     if( m_changedItems.find( aItem ) != m_changedItems.end() )
     {
-        alg::delete_if( m_changes, [aItem]( const COMMIT_LINE& aEnt )
+        alg::delete_if( m_changes, [aItem, aScreen]( const COMMIT_LINE& aEnt )
                                    {
-                                       return aEnt.m_item == aItem;
+                                       return aEnt.m_item == aItem && aEnt.m_screen == aScreen;
                                    } );
     }
 
@@ -163,17 +164,18 @@ void COMMIT::makeEntry( EDA_ITEM* aItem, CHANGE_TYPE aType, EDA_ITEM* aCopy )
     ent.m_item = aItem;
     ent.m_type = aType;
     ent.m_copy = aCopy;
+    ent.m_screen = aScreen;
 
     m_changedItems.insert( aItem );
     m_changes.push_back( ent );
 }
 
 
-COMMIT::COMMIT_LINE* COMMIT::findEntry( EDA_ITEM* aItem )
+COMMIT::COMMIT_LINE* COMMIT::findEntry( EDA_ITEM* aItem, BASE_SCREEN *aScreen )
 {
     for( COMMIT_LINE& change : m_changes )
     {
-        if( change.m_item == aItem )
+        if( change.m_item == aItem && change.m_screen == aScreen )
             return &change;
     }