Properly handle improper symbols when pasting in symbol editor

Before, an improper symbol (one without the starting toekn) weren't
detected and reported to the user properly and would instead assert. Now
properly detect these and pass the error up the stack to the tool.

(Sentry issue KICAD-21J).

eeschema/sch_plugins/kicad/sch_sexpr_parser.cpp

@@ -152,7 +152,7 @@ void SCH_SEXPR_PARSER::ParseLib( LIB_SYMBOL_MAP& aSymbolLibMap )
         {
             m_unit = 1;
             m_convert = 1;
-            LIB_SYMBOL* symbol = ParseSymbol( aSymbolLibMap, m_requiredVersion );
+            LIB_SYMBOL* symbol = parseLibSymbol( aSymbolLibMap );
             aSymbolLibMap[symbol->GetName()] = symbol;
         }
         else
@@ -164,6 +164,34 @@ void SCH_SEXPR_PARSER::ParseLib( LIB_SYMBOL_MAP& aSymbolLibMap )
 
 
 LIB_SYMBOL* SCH_SEXPR_PARSER::ParseSymbol( LIB_SYMBOL_MAP& aSymbolLibMap, int aFileVersion )
+{
+    LIB_SYMBOL* newSymbol = nullptr;
+
+    NextTok();
+
+    // If there actually isn't anything here, don't throw just return a nullptr
+    if( CurTok() == T_LEFT )
+    {
+        NextTok();
+
+        if( CurTok() == T_symbol )
+        {
+            m_requiredVersion = aFileVersion;
+            newSymbol         = parseLibSymbol( aSymbolLibMap );
+        }
+        else
+        {
+            wxString msg = wxString::Format( _( "Cannot parse %s as a symbol" ),
+                                             GetTokenString( CurTok() ) );
+            THROW_PARSE_ERROR( msg, CurSource(), CurLine(), CurLineNumber(), CurOffset() );
+        }
+    }
+
+    return newSymbol;
+}
+
+
+LIB_SYMBOL* SCH_SEXPR_PARSER::parseLibSymbol( LIB_SYMBOL_MAP& aSymbolLibMap )
 {
     wxCHECK_MSG( CurTok() == T_symbol, nullptr,
                  wxT( "Cannot parse " ) + GetTokenString( CurTok() ) + wxT( " as a symbol." ) );
@@ -176,7 +204,6 @@ LIB_SYMBOL* SCH_SEXPR_PARSER::ParseSymbol( LIB_SYMBOL_MAP& aSymbolLibMap, int aF
     LIB_ITEM* item;
     std::unique_ptr<LIB_SYMBOL> symbol = std::make_unique<LIB_SYMBOL>( wxEmptyString );
 
-    m_requiredVersion = aFileVersion;
     symbol->SetUnitCount( 1 );
 
     m_fieldId = MANDATORY_FIELDS;
@@ -2398,7 +2425,7 @@ void SCH_SEXPR_PARSER::ParseSchematic( SCH_SHEET* aSheet, bool aIsCopyableOnly,
                 switch( token )
                 {
                 case T_symbol:
-                    symbol = ParseSymbol( symbolLibMap, m_requiredVersion );
+                    symbol = parseLibSymbol( symbolLibMap );
                     symbol->UpdateFieldOrdinals();
                     screen->AddLibSymbol( symbol );
                     break;

eeschema/sch_plugins/kicad/sch_sexpr_parser.h

@@ -83,6 +83,9 @@ public:
 
     void ParseLib( LIB_SYMBOL_MAP& aSymbolLibMap );
 
+    /**
+     * Parse internal #LINE_READER object into symbols and return all found.
+     */
     LIB_SYMBOL* ParseSymbol( LIB_SYMBOL_MAP& aSymbolLibMap,
                              int aFileVersion = SEXPR_SYMBOL_LIB_FILE_VERSION );
 
@@ -155,6 +158,8 @@ private:
 
     bool parseBool();
 
+    LIB_SYMBOL* parseLibSymbol( LIB_SYMBOL_MAP& aSymbolLibMap );
+
     /**
      * Parse stroke definition \a aStroke.
      *

eeschema/sch_plugins/kicad/sch_sexpr_plugin.cpp

@@ -1658,16 +1658,31 @@ void SCH_SEXPR_PLUGIN::GetDefaultSymbolFields( std::vector<wxString>& aNames )
 }
 
 
-LIB_SYMBOL* SCH_SEXPR_PLUGIN::ParseLibSymbol( LINE_READER& aReader, int aFileVersion )
+std::vector<LIB_SYMBOL*> SCH_SEXPR_PLUGIN::ParseLibSymbols( std::string& aSymbolText,
+                                                            std::string  aSource,
+                                                            int aFileVersion )
 {
     LOCALE_IO      toggle;     // toggles on, then off, the C locale.
+    LIB_SYMBOL*    newSymbol = nullptr;
     LIB_SYMBOL_MAP map;
-    SCH_SEXPR_PARSER parser( &aReader );
 
-    parser.NeedLEFT();
+    std::vector<LIB_SYMBOL*>            newSymbols;
-    parser.NextTok();
+    std::unique_ptr<STRING_LINE_READER> reader = std::make_unique<STRING_LINE_READER>( aSymbolText, aSource );
 
-    return parser.ParseSymbol( map, aFileVersion );
+    do
+    {
+        SCH_SEXPR_PARSER parser( reader.get() );
+
+        newSymbol = parser.ParseSymbol( map, aFileVersion );
+
+        if( newSymbol )
+            newSymbols.emplace_back( newSymbol );
+
+        reader.reset( new STRING_LINE_READER( *reader ) );
+    }
+    while( newSymbol );
+
+    return newSymbols;
 }
 
 

eeschema/sch_plugins/kicad/sch_sexpr_plugin.h

@@ -137,8 +137,9 @@ public:
 
     const wxString& GetError() const override { return m_error; }
 
-    static LIB_SYMBOL* ParseLibSymbol( LINE_READER& aReader,
+    static std::vector<LIB_SYMBOL*> ParseLibSymbols( std::string& aSymbolText,
-                                       int aVersion = SEXPR_SCHEMATIC_FILE_VERSION );
+                                                     std::string  aSource,
+                                                     int aFileVersion = SEXPR_SCHEMATIC_FILE_VERSION );
     static void FormatLibSymbol( LIB_SYMBOL* aPart, OUTPUTFORMATTER& aFormatter );
 
 private:

eeschema/symbol_editor/symbol_editor.cpp

@@ -852,43 +852,16 @@ void SYMBOL_EDIT_FRAME::DuplicateSymbol( bool aFromClipboard )
 
     if( aFromClipboard )
     {
-        wxLogNull doNotLog; // disable logging of failed clipboard actions
+        std::string clipboardData = m_toolManager->GetClipboardUTF8();
 
-        auto clipboard = wxTheClipboard;
-        wxClipboardLocker clipboardLock( clipboard );
-
-        if( !clipboardLock
-            || !( clipboard->IsSupported( wxDF_TEXT )
-                  || clipboard->IsSupported( wxDF_UNICODETEXT ) ) )
-        {
-            return;
-        }
-
-        wxTextDataObject data;
-        clipboard->GetData( data );
-        wxString symbolSource = data.GetText();
-
-        std::unique_ptr<STRING_LINE_READER> reader = std::make_unique<STRING_LINE_READER>( TO_UTF8( symbolSource ), wxS( "Clipboard" ) );
-        LIB_SYMBOL* newSymbol = nullptr;
-
-        do
-        {
         try
         {
-                newSymbol = SCH_SEXPR_PLUGIN::ParseLibSymbol( *reader );
+            newSymbols = SCH_SEXPR_PLUGIN::ParseLibSymbols( clipboardData, "Clipboard" );
         }
         catch( IO_ERROR& e )
         {
             wxLogMessage( wxS( "Can not paste: %s" ), e.Problem() );
-                break;
         }
-
-            if( newSymbol )
-                newSymbols.emplace_back( newSymbol );
-
-            reader.reset( new STRING_LINE_READER( *reader ) );
-        }
-        while( newSymbol );
     }
     else
     {

eeschema/tools/symbol_editor_edit_tool.cpp

@@ -759,30 +759,31 @@ int SYMBOL_EDITOR_EDIT_TOOL::Copy( const TOOL_EVENT& aEvent )
 int SYMBOL_EDITOR_EDIT_TOOL::Paste( const TOOL_EVENT& aEvent )
 {
     LIB_SYMBOL* symbol  = m_frame->GetCurSymbol();
+    LIB_SYMBOL* newPart = nullptr;
 
     if( !symbol || symbol->IsAlias() )
         return 0;
 
-    std::string         text_utf8 = m_toolMgr->GetClipboardUTF8();
+    std::string clipboardData = m_toolMgr->GetClipboardUTF8();
-    STRING_LINE_READER  reader( text_utf8, "Clipboard" );
-    LIB_SYMBOL*         newPart;
 
     try
     {
-        newPart = SCH_SEXPR_PLUGIN::ParseLibSymbol( reader );
+        std::vector<LIB_SYMBOL*> newParts = SCH_SEXPR_PLUGIN::ParseLibSymbols( clipboardData, "Clipboard" );
+
+        if( newParts.empty() || !newParts[0] )
+            return -1;
+
+        newPart = newParts[0];
     }
     catch( IO_ERROR& )
     {
         // If it's not a symbol then paste as text
         newPart = new LIB_SYMBOL( "dummy_part" );
         LIB_TEXT* newText = new LIB_TEXT( newPart );
-        newText->SetText( wxString::FromUTF8( text_utf8.c_str() ) );
+        newText->SetText( clipboardData );
         newPart->AddDrawItem( newText );
     }
 
-    if( !newPart )
-        return -1;
-
     SCH_COMMIT commit( m_toolMgr );
 
     commit.Modify( symbol );