Don't allow updates to shown_text outside of cacheShownText().

But also don't use cacheShownText() in c'tors, as it will not call
the subclass's version.

common/eda_text.cpp

@@ -95,7 +95,17 @@ EDA_TEXT::EDA_TEXT( const EDA_IU_SCALE& aIuScale, const wxString& aText ) :
 {
     SetTextSize( VECTOR2I( EDA_UNIT_UTILS::Mils2IU( m_IuScale, DEFAULT_SIZE_TEXT ),
                            EDA_UNIT_UTILS::Mils2IU( m_IuScale, DEFAULT_SIZE_TEXT ) ) );
-    cacheShownText();
+
+    if( m_text.IsEmpty() )
+    {
+        m_shown_text = wxEmptyString;
+        m_shown_text_has_text_var_refs = false;
+    }
+    else
+    {
+        m_shown_text = UnescapeString( m_text );
+        m_shown_text_has_text_var_refs = m_shown_text.Contains( wxT( "${" ) );
+    }
 }
 
 
@@ -170,22 +180,14 @@ EDA_TEXT& EDA_TEXT::operator=( const EDA_TEXT& aText )
 void EDA_TEXT::SetText( const wxString& aText )
 {
     m_text = aText;
-
     cacheShownText();
-
-    ClearRenderCache();
-    m_bounding_box_cache_valid = false;
 }
 
 
 void EDA_TEXT::CopyText( const EDA_TEXT& aSrc )
 {
     m_text = aSrc.m_text;
-    m_shown_text = aSrc.m_shown_text;
-    m_shown_text_has_text_var_refs = aSrc.m_shown_text_has_text_var_refs;
-
-    ClearRenderCache();
-    m_bounding_box_cache_valid = false;
+    cacheShownText();
 }
 
 
@@ -280,11 +282,7 @@ void EDA_TEXT::SetAttributes( const EDA_TEXT& aSrc )
 void EDA_TEXT::SwapText( EDA_TEXT& aTradingPartner )
 {
     std::swap( m_text, aTradingPartner.m_text );
-    std::swap( m_shown_text, aTradingPartner.m_shown_text );
-    std::swap( m_shown_text_has_text_var_refs, aTradingPartner.m_shown_text_has_text_var_refs );
-
-    ClearRenderCache();
-    m_bounding_box_cache_valid = false;
+    cacheShownText();
 }
 
 

eeschema/sch_label.cpp

@@ -161,7 +161,10 @@ SCH_LABEL_BASE::SCH_LABEL_BASE( const VECTOR2I& aPos, const wxString& aText, KIC
         m_lastResolvedColor( COLOR4D::UNSPECIFIED )
 {
     SetMultilineAllowed( false );
-    ClearFieldsAutoplaced();    // fiels are not yet autoplaced.
+    ClearFieldsAutoplaced();    // fields are not yet autoplaced.
+
+    if( !HasTextVars() )
+        m_cached_driver_name = EscapeString( EDA_TEXT::GetShownText( true, 0 ), CTX_NETNAME );
 }
 
 
@@ -170,7 +173,8 @@ SCH_LABEL_BASE::SCH_LABEL_BASE( const SCH_LABEL_BASE& aLabel ) :
         m_shape( aLabel.m_shape ),
         m_connectionType( aLabel.m_connectionType ),
         m_isDangling( aLabel.m_isDangling ),
-        m_lastResolvedColor( aLabel.m_lastResolvedColor )
+        m_lastResolvedColor( aLabel.m_lastResolvedColor ),
+        m_cached_driver_name( aLabel.m_cached_driver_name )
 {
     SetMultilineAllowed( false );
 
@@ -181,6 +185,16 @@ SCH_LABEL_BASE::SCH_LABEL_BASE( const SCH_LABEL_BASE& aLabel ) :
 }
 
 
+SCH_LABEL_BASE& SCH_LABEL_BASE::operator=( const SCH_LABEL_BASE& aLabel )
+{
+    SCH_TEXT::operator=( aLabel );
+
+    m_cached_driver_name = aLabel.m_cached_driver_name;
+
+    return *this;
+}
+
+
 const wxString SCH_LABEL_BASE::GetDefaultFieldName( const wxString& aName, bool aUseDefaultName )
 {
     if( aName == wxT( "Intersheetrefs" ) )

eeschema/sch_label.h

@@ -38,6 +38,8 @@ public:
 
     SCH_LABEL_BASE( const SCH_LABEL_BASE& aLabel );
 
+    SCH_LABEL_BASE& operator=( const SCH_LABEL_BASE& aLabel );
+
     // Abstract class
     virtual wxString GetClass() const override = 0;