Assure that NETINFO_ITEMs have a NETCLASS object assigned

Fixes: lp:1705896
* https://bugs.launchpad.net/kicad/+bug/1705896

pcbnew/class_netclass.cpp

@@ -86,7 +86,6 @@ NETCLASS::~NETCLASS()
 
 NETCLASSES::NETCLASSES()
 {
-    m_Default = std::make_shared<NETCLASS>( NETCLASS::Default );
 }
 
 
@@ -102,7 +101,7 @@ bool NETCLASSES::Add( NETCLASSPTR aNetClass )
     if( name == NETCLASS::Default )
     {
         // invoke operator=(), which is currently generated by compiler.
-        m_Default = aNetClass;
+        GetDefault() = aNetClass;
 
         return true;
     }
@@ -142,7 +141,7 @@ NETCLASSPTR NETCLASSES::Remove( const wxString& aNetName )
 NETCLASSPTR NETCLASSES::Find( const wxString& aName ) const
 {
     if( aName == NETCLASS::Default )
-        return m_Default;
+        return GetDefault();
 
     NETCLASS_MAP::const_iterator found = m_NetClasses.find( aName );
 

pcbnew/class_netclass.h

@@ -235,9 +235,6 @@ private:
     /// all the NETCLASSes except the default one.
     NETCLASS_MAP    m_NetClasses;
 
-    /// the default NETCLASS.
-    NETCLASSPTR     m_Default;
-
 public:
     NETCLASSES();
     ~NETCLASSES();
@@ -272,9 +269,10 @@ public:
      * Function GetDefault
      * @return the default net class.
      */
-    NETCLASSPTR GetDefault() const
+    NETCLASSPTR& GetDefault() const
     {
-        return m_Default;
+        static NETCLASSPTR defNetClass = std::make_shared<NETCLASS>( NETCLASS::Default );
+        return defNetClass;
     }
 
     /**

pcbnew/class_netinfo.h

@@ -78,9 +78,6 @@ private:
 
     wxString m_ShortNetname;    ///< short net name, like vout from /mysheet/mysubsheet/vout
 
-    wxString  m_NetClassName;   // Net Class name. if void this is equivalent
-                                // to "default" (the first
-                                // item of the net classes list
     NETCLASSPTR m_NetClass;
 
     BOARD*  m_parent;           ///< The parent board the net belongs to.
@@ -120,15 +117,7 @@ public:
      * Function SetClass
      * sets \a aNetclass into this NET
      */
-    void SetClass( NETCLASSPTR aNetClass )
-    {
-        m_NetClass = aNetClass;
-
-        if( aNetClass )
-            m_NetClassName = aNetClass->GetName();
-        else
-            m_NetClassName = NETCLASS::Default;
-    }
+    void SetClass( NETCLASSPTR aNetClass );
 
     NETCLASSPTR GetNetClass()
     {
@@ -139,9 +128,9 @@ public:
      * Function GetClassName
      * returns the class name
      */
-    const wxString& GetClassName() const
+    wxString GetClassName() const
     {
-        return m_NetClassName;
+        return m_NetClass ? m_NetClass->GetName() : NETCLASS::Default;
     }
 
 #if 1

pcbnew/class_netinfo_item.cpp

@@ -53,8 +53,12 @@ NETINFO_ITEM::NETINFO_ITEM( BOARD* aParent, const wxString& aNetName, int aNetCo
     BOARD_ITEM( aParent, PCB_NETINFO_T ),
     m_NetCode( aNetCode ), m_Netname( aNetName ), m_ShortNetname( m_Netname.AfterLast( '/' ) )
 {
-    m_parent   = aParent;
-    m_NetClassName = NETCLASS::Default;
+    m_parent = aParent;
+
+    if( aParent )
+        m_NetClass = aParent->GetDesignSettings().m_NetClasses.GetDefault();
+    else
+        m_NetClass = std::make_shared<NETCLASS>( "<invalid>" );
 }
 
 
@@ -75,6 +79,13 @@ void NETINFO_ITEM::Draw( EDA_DRAW_PANEL* panel,
 }
 
 
+void NETINFO_ITEM::SetClass( NETCLASSPTR aNetClass )
+{
+    wxCHECK( m_parent, /* void */ );
+    m_NetClass = aNetClass ? aNetClass : m_parent->GetDesignSettings().m_NetClasses.GetDefault();
+}
+
+
 void NETINFO_ITEM::GetMsgPanelInfo( std::vector< MSG_PANEL_ITEM >& aList )
 {
     wxString  txt;