Better handling of undefined values in Rule expressions.

This is particularly important to keep the user from having to
enter overly verbose statements such as:
A.Type == 'via' && A.Via_Type == 'buried'
when:
A.Via_Type == 'buried'
is perfectly clear.

common/base_struct.cpp

@@ -744,9 +744,8 @@ static struct EDA_ITEM_DESC
     EDA_ITEM_DESC()
     {
         ENUM_MAP<KICAD_T>::Instance()
+            .Undefined( TYPE_NOT_INIT )
             .Map( NOT_USED,             wxT( "<not used>" ) )
-            //.Map( EOT,                  wxT( "<EOT>" ) )
-            .Map( TYPE_NOT_INIT,        wxT( "<type not init>" ) )    // == EOT
             .Map( SCREEN_T,             _( "Screen" ) )
 
             .Map( PCB_MODULE_T,         _( "Footprint" ) )
@@ -799,9 +798,7 @@ static struct EDA_ITEM_DESC
 
             .Map( GERBER_LAYOUT_T,      _( "Gerber Layout" ) )
             .Map( GERBER_DRAW_ITEM_T,   _( "Draw Item" ) )
-            .Map( GERBER_IMAGE_T,       _( "Image" ) )
-
-            .Map( MAX_STRUCT_TYPE_ID,   wxT( "<max struct type>" ) );
+            .Map( GERBER_IMAGE_T,       _( "Image" ) );
 
         PROPERTY_MANAGER& propMgr = PROPERTY_MANAGER::Instance();
         REGISTER_TYPE( EDA_ITEM );

common/libeval_compiler/libeval_compiler.cpp

@@ -787,7 +787,7 @@ void UOP::Exec( CONTEXT* ctx, UCODE* ucode )
     case TR_UOP_PUSH_VAR:
     {
         auto value = ctx->AllocValue();
-        value->Set( reinterpret_cast<VAR_REF*>( m_arg )->GetValue( ctx, ucode ) );
+        value->Set( reinterpret_cast<VAR_REF*>( m_arg )->GetValue( ucode ) );
         ctx->Push( value );
     }
         break;

include/libeval_compiler/libeval_compiler.h

@@ -249,7 +249,7 @@ class VAR_REF
 {
 public:
     virtual VAR_TYPE_T GetType() = 0;
-    virtual VALUE GetValue( CONTEXT* aCtx, UCODE* aUcode ) = 0;
+    virtual VALUE GetValue( UCODE* aUcode ) = 0;
 };
 
 

include/property.h

@@ -528,14 +528,22 @@ public:
         return *this;
     }
 
-    void SetDefault( T aValue )
+    ENUM_MAP& Undefined( T aValue )
     {
-        m_default = aValue;
+        m_undefined = aValue;
+        return *this;
     }
 
     const wxString& ToString( T value ) const
     {
+        static const wxString s_undef = "UNDEFINED";
+
+        int idx = static_cast<int>( value );
+
+        if( idx >= 0 && idx < (int) m_choices.GetCount() )
             return m_choices.GetLabel( static_cast<int>( value ) );
+        else
+            return s_undef;
     }
 
     const T ToEnum( const wxString value )
@@ -543,7 +551,7 @@ public:
         if( m_reverseMap.count( value ) )
             return m_reverseMap[ value ];
         else
-            return m_default;
+            return m_undefined;
     }
 
     wxPGChoices& Choices()
@@ -554,7 +562,7 @@ public:
 private:
     wxPGChoices                     m_choices;
     std::unordered_map<wxString, T> m_reverseMap;
-    T                               m_default;      // Returned if the string is not recognized
+    T                               m_undefined;      // Returned if the string is not recognized
 
     ENUM_MAP<T>()
     {

pcbnew/board_connected_item.cpp

@@ -208,7 +208,7 @@ static struct BOARD_CONNECTED_ITEM_DESC
 
         if( layerEnum.Choices().GetCount() == 0 )
         {
-            layerEnum.SetDefault( UNDEFINED_LAYER );
+            layerEnum.Undefined( UNDEFINED_LAYER );
 
             for( LSEQ seq = LSET::AllLayersMask().Seq(); seq; ++seq )
                 layerEnum.Map( *seq, LSET::Name( *seq ) );

pcbnew/class_board_item.cpp

@@ -147,7 +147,7 @@ static struct BOARD_ITEM_DESC
 
         if( layerEnum.Choices().GetCount() == 0 )
         {
-            layerEnum.SetDefault( UNDEFINED_LAYER );
+            layerEnum.Undefined( UNDEFINED_LAYER );
 
             for( LSEQ seq = LSET::AllLayersMask().Seq(); seq; ++seq )
                 layerEnum.Map( *seq, LSET::Name( *seq ) );

pcbnew/class_track.cpp

@@ -983,6 +983,7 @@ static struct TRACK_VIA_DESC
     TRACK_VIA_DESC()
     {
         ENUM_MAP<VIATYPE>::Instance()
+            .Undefined( VIATYPE::NOT_DEFINED )
             .Map( VIATYPE::THROUGH, _( "Through" ) )
             .Map( VIATYPE::BLIND_BURIED, _( "Blind/Buried" ) )
             .Map( VIATYPE::MICROVIA, _( "Microvia" ) );

pcbnew/pcb_edit_frame.cpp

@@ -470,7 +470,7 @@ void PCB_EDIT_FRAME::ReFillLayerWidget()
     ENUM_MAP<PCB_LAYER_ID>& layerEnum = ENUM_MAP<PCB_LAYER_ID>::Instance();
 
     layerEnum.Choices().Clear();
-    layerEnum.SetDefault( UNDEFINED_LAYER );
+    layerEnum.Undefined( UNDEFINED_LAYER );
 
     for( LSEQ seq = LSET::AllLayersMask().Seq(); seq; ++seq )
         layerEnum.Map( *seq, GetBoard()->GetLayerName( *seq ) );

pcbnew/pcb_expr_evaluator.cpp

@@ -99,17 +99,18 @@ BOARD_ITEM* PCB_EXPR_VAR_REF::GetObject( LIBEVAL::UCODE* aUcode ) const
 }
 
 
-LIBEVAL::VALUE PCB_EXPR_VAR_REF::GetValue( LIBEVAL::CONTEXT* aCtx, LIBEVAL::UCODE* aUcode )
+LIBEVAL::VALUE PCB_EXPR_VAR_REF::GetValue( LIBEVAL::UCODE* aUcode )
 {
     BOARD_ITEM* item  = const_cast<BOARD_ITEM*>( GetObject( aUcode ) );
     auto        it = m_matchingTypes.find( TYPE_HASH( *item ) );
 
     if( it == m_matchingTypes.end() )
     {
-        wxString msg;
-        msg.Printf("property not found for item of type: 0x%x!\n",  TYPE_HASH( *item ) );
-        aCtx->ReportError( (const char *) msg.c_str() );
-        return LIBEVAL::VALUE( 0.0 );
+        // Don't force user to type "A.Type == 'via' && A.Via_Type == 'buried'" when the
+        // simplier "A.Via_Type == 'buried'" is perfectly clear.  Instead, return an undefined
+        // value when the property doesn't appear on a particular object.
+
+        return LIBEVAL::VALUE( "UNDEFINED" );
     }
     else
     {
@@ -118,6 +119,7 @@ LIBEVAL::VALUE PCB_EXPR_VAR_REF::GetValue( LIBEVAL::CONTEXT* aCtx, LIBEVAL::UCOD
         else
         {
             wxString str;
+
             if( !m_isEnum )
             {
                 //printf("item %p Get string '%s'\n", item, (const char*) it->second->Name().c_str() );
@@ -125,10 +127,11 @@ LIBEVAL::VALUE PCB_EXPR_VAR_REF::GetValue( LIBEVAL::CONTEXT* aCtx, LIBEVAL::UCOD
             }
             else
             {
-                const auto& any = item->Get( it->second );
+                const wxAny& any = item->Get( it->second );
                 any.GetAs<wxString>( &str );
                 //printf("item %p get enum: '%s'\n", item , (const char*) str.c_str() );
             }
+
             return LIBEVAL::VALUE( (const char*) str.c_str() );
         }
     }

pcbnew/pcb_expr_evaluator.h

@@ -85,7 +85,7 @@ public:
         m_matchingTypes[type_hash] = prop;
     }
 
-    virtual LIBEVAL::VALUE GetValue( LIBEVAL::CONTEXT* aCtx, LIBEVAL::UCODE* aUcode ) override;
+    virtual LIBEVAL::VALUE GetValue( LIBEVAL::UCODE* aUcode ) override;
 
     BOARD_ITEM* GetObject( LIBEVAL::UCODE* aUcode ) const;