Clear annotation of pasted sheets only when they already exist in the current hierarchy.

Fixes: lp:1833205
* https://bugs.launchpad.net/kicad/+bug/1833205

eeschema/sch_legacy_plugin.cpp

@@ -670,7 +670,7 @@ void SCH_LEGACY_PLUGIN::loadHierarchy( SCH_SHEET* aSheet )
         wxLogTrace( traceSchLegacyPlugin, "Current path   \"%s\"", m_currentPath.top() );
         wxLogTrace( traceSchLegacyPlugin, "Loading        \"%s\"", fileName.GetFullPath() );
 
-        m_rootSheet->SearchHierarchy( fileName.GetFullPath(), &screen );
+        m_rootSheet->SearchHierarchy( fileName.GetFullPath( wxPATH_UNIX ), &screen );
 
         if( screen )
         {

eeschema/sch_sheet.cpp

@@ -548,17 +548,21 @@ bool SCH_SHEET::SearchHierarchy( const wxString& aFilename, SCH_SCREEN** aScreen
         {
             if( item->Type() == SCH_SHEET_T )
             {
-                SCH_SHEET* sheet = (SCH_SHEET*) item;
+                // Must use the screen's path (which is always absolute) rather than the
+                // sheet's (which could be relative).
 
-                if( sheet->m_screen
+                SCH_SHEET*  sheet = (SCH_SHEET*) item;
-                    && sheet->m_screen->GetFileName().CmpNoCase( aFilename ) == 0 )
+                SCH_SCREEN* screen = sheet->m_screen;
+
+                if( screen && screen->GetFileName().CmpNoCase( aFilename ) == 0 )
                 {
-                    *aScreen = sheet->m_screen;
+                    *aScreen = screen;
                     return true;
                 }
-
+                else if( sheet->SearchHierarchy( aFilename, aScreen ) )
-                if( sheet->SearchHierarchy( aFilename, aScreen ) )
+                {
                     return true;
+                }
             }
 
             item = item->Next();

eeschema/sch_sheet.h

@@ -418,7 +418,7 @@ public:
     /**
      * Search the existing hierarchy for an instance of screen loaded from \a aFileName.
      *
-     * @param aFilename = the filename to find
+     * @param aFilename = the filename to find (MUST be absolute, and in wxPATH_UNIX encoding)
      * @param aScreen = a location to return a pointer to the screen (if found)
      * @return bool if found, and a pointer to the screen
      */

eeschema/sheet.cpp

@@ -131,10 +131,10 @@ bool SCH_EDIT_FRAME::EditSheet( SCH_SHEET* aSheet, SCH_SHEET_PATH* aHierarchy,
                      "Cannot normalize new sheet schematic file path." );
     }
 
-    wxString newFilename = fileName.GetFullPath();
+    wxString newFilename = fileName.GetFullPath( wxPATH_UNIX );
 
-    // Search for a schematic file having the same filename
+    // Search for a schematic file having the same filename already in use in the hierarchy
-    // already in use in the hierarchy or on disk, in order to reuse it.
+    // or on disk, in order to reuse it.
     if( !g_RootSheet->SearchHierarchy( newFilename, &useScreen ) )
     {
         loadFromFile = wxFileExists( newFilename );

eeschema/tools/sch_editor_control.cpp

@@ -833,8 +833,6 @@ int SCH_EDITOR_CONTROL::Paste( const TOOL_EVENT& aEvent )
     //
     bool           sheetsPasted = false;
     SCH_SHEET_LIST hierarchy( g_RootSheet );
-    SCH_SHEET_LIST initialHierarchy( g_RootSheet );
-
     wxFileName     destFn = g_CurrentSheet->Last()->GetFileName();
 
     if( destFn.IsRelative() )
@@ -909,12 +907,33 @@ int SCH_EDITOR_CONTROL::Paste( const TOOL_EVENT& aEvent )
         else if( item->Type() == SCH_SHEET_T )
         {
             SCH_SHEET*  sheet = (SCH_SHEET*) item;
+            wxFileName  fn = sheet->GetFileName();
             SCH_SCREEN* existingScreen = nullptr;
 
-            if( g_RootSheet->SearchHierarchy( sheet->GetFileName(), &existingScreen ) )
+            if( !fn.IsAbsolute() )
+            {
+                wxFileName currentSheetFileName = g_CurrentSheet->LastScreen()->GetFileName();
+                fn.Normalize( wxPATH_NORM_ALL, currentSheetFileName.GetPath() );
+            }
+
+            if( g_RootSheet->SearchHierarchy( fn.GetFullPath( wxPATH_UNIX ), &existingScreen ) )
+            {
                 sheet->SetScreen( existingScreen );
+
+                SCH_SHEET_PATH sheetpath = *g_CurrentSheet;
+                sheetpath.push_back( sheet );
+
+                // Clear annotation and create the AR for this path, if not exists,
+                // when the screen is shared by sheet paths.
+                // Otherwise ClearAnnotation do nothing, because the F1 field is used as
+                // reference default value and takes the latest displayed value
+                existingScreen->EnsureAlternateReferencesExist();
+                existingScreen->ClearAnnotation( &sheetpath );
+            }
             else
+            {
                 m_frame->LoadSheetFromFile( sheet, g_CurrentSheet, sheet->GetFileName() );
+            }
         }
 
         item->SetFlags( IS_NEW | IS_PASTED | IS_MOVED );
@@ -925,12 +944,7 @@ int SCH_EDITOR_CONTROL::Paste( const TOOL_EVENT& aEvent )
     }
 
     if( sheetsPasted )
-    {
-        // We clear annotation of new sheet paths.
-        SCH_SCREENS screensList( g_RootSheet );
-        screensList.ClearAnnotationOfNewSheetPaths( initialHierarchy );
         m_frame->SetSheetNumberAndCount();
-    }
 
     // Now clear the previous selection, select the pasted items, and fire up the "move"
     // tool.