Eeschema: Force output ordering

The RTree does not have a deterministic iterator, so extracting items
may be in arbitrary order, causing issues as the schematic appears to
change when comparing to previous revisions.

This uses the SCH_ITEM comparison operator to for ordering by type, then
by custom sorting within type.

For the netlist, we choose the first available unit in the sheet for
each component.

Fixes #3811 | https://gitlab.com/kicad/code/kicad/issues/3811

eeschema/netlist_exporters/netlist_exporter_generic.cpp

@@ -212,7 +212,30 @@ XNODE* NETLIST_EXPORTER_GENERIC::makeComponents()
 
     for( unsigned i = 0;  i < sheetList.size();  i++ )
     {
+
+        auto cmp = []( const SCH_COMPONENT* a, const SCH_COMPONENT* b ) {
+            return a->GetField( REFERENCE )->GetText() < b->GetField( REFERENCE )->GetText();
+        };
+
+        std::set<SCH_COMPONENT*, decltype( cmp )> ordered_components( cmp );
+
         for( auto item : sheetList[i].LastScreen()->Items().OfType( SCH_COMPONENT_T ) )
+        {
+            auto comp = static_cast<SCH_COMPONENT*>( item );
+            auto test = ordered_components.insert( comp );
+
+            if( !test.second )
+            {
+                if( ( *( test.first ) )->GetUnit() > comp->GetUnit() )
+                {
+                    ordered_components.erase( test.first );
+                    ordered_components.insert( comp );
+                }
+            }
+        }
+
+
+        for( auto item : ordered_components )
         {
             SCH_COMPONENT* comp = findNextComponent( item, &sheetList[i] );
 

eeschema/sch_component.cpp

@@ -1714,7 +1714,7 @@ bool SCH_COMPONENT::operator <( const SCH_ITEM& aItem ) const
     if( Type() != aItem.Type() )
         return Type() < aItem.Type();
 
-    SCH_COMPONENT* component = (SCH_COMPONENT*) &aItem;
+    auto component = static_cast<const SCH_COMPONENT*>( &aItem );
 
     EDA_RECT rect = GetBodyBoundingBox();
 
@@ -1727,7 +1727,7 @@ bool SCH_COMPONENT::operator <( const SCH_ITEM& aItem ) const
     if( m_Pos.y != component->m_Pos.y )
         return m_Pos.y < component->m_Pos.y;
 
-    return false;
+    return GetTimeStamp() < aItem.GetTimeStamp();
 }
 
 

eeschema/sch_item.cpp

@@ -171,8 +171,18 @@ void SCH_ITEM::SwapData( SCH_ITEM* aItem )
 
 bool SCH_ITEM::operator < ( const SCH_ITEM& aItem ) const
 {
-    wxCHECK_MSG( false, this->Type() < aItem.Type(),
-                 wxT( "Less than operator not defined for " ) + GetClass() );
+    bool retval = ( Type() < aItem.Type() );
+
+    if( Type() != aItem.Type() )
+        return Type() < aItem.Type();
+
+    if( GetTimeStamp() != aItem.GetTimeStamp() )
+        return GetTimeStamp() < aItem.GetTimeStamp();
+
+    if( GetPosition().x != aItem.GetPosition().x )
+        return GetPosition().x < aItem.GetPosition().x;
+
+    return GetPosition().y < aItem.GetPosition().y;
 }
 
 

eeschema/sch_legacy_plugin.cpp

@@ -23,10 +23,12 @@
 #include <algorithm>
 #include <boost/algorithm/string/join.hpp>
 #include <cctype>
+#include <set>
 
 #include <wx/mstream.h>
 #include <wx/filename.h>
 #include <wx/tokenzr.h>
+
 #include <pgm_base.h>
 #include <gr_text.h>
 #include <kiway.h>
@@ -1877,7 +1879,15 @@ void SCH_LEGACY_PLUGIN::Format( SCH_SCREEN* aScreen )
         saveBusAlias( alias );
     }
 
+    // Enforce item ordering
+    auto cmp = []( const SCH_ITEM* a, const SCH_ITEM* b ) { return *a < *b; };
+    std::multiset<SCH_ITEM*, decltype( cmp )> save_map( cmp );
+
     for( auto item : aScreen->Items() )
+        save_map.insert( item );
+
+
+    for( auto& item : save_map )
     {
         switch( item->Type() )
         {

eeschema/sch_line.cpp

@@ -689,7 +689,7 @@ bool SCH_LINE::operator <( const SCH_ITEM& aItem ) const
     if( Type() != aItem.Type() )
         return Type() < aItem.Type();
 
-    SCH_LINE* line = (SCH_LINE*) &aItem;
+    auto line = static_cast<const SCH_LINE*>( &aItem );
 
     if( GetLength() != line->GetLength() )
         return GetLength() < line->GetLength();

eeschema/sch_text.cpp

@@ -263,6 +263,24 @@ void SCH_TEXT::SwapData( SCH_ITEM* aItem )
 }
 
 
+bool SCH_TEXT::operator<( const SCH_ITEM& aItem ) const
+{
+    if( Type() != aItem.Type() )
+        return Type() < aItem.Type();
+
+    auto other = static_cast<const SCH_TEXT*>( &aItem );
+
+
+    if( GetPosition().x != other->GetPosition().x )
+        return GetPosition().x < other->GetPosition().x;
+
+    if( GetPosition().y != other->GetPosition().y )
+        return GetPosition().y < other->GetPosition().y;
+
+    return GetText() < other->GetText();
+}
+
+
 int SCH_TEXT::GetPenSize() const
 {
     int pensize = GetThickness();

eeschema/sch_text.h

@@ -270,6 +270,8 @@ public:
 
     const EDA_RECT GetBoundingBox() const override;
 
+    bool operator<( const SCH_ITEM& aItem ) const override;
+
     int GetPenSize() const override;
 
     // Geometric transforms (used in block operations):