Resolves: tdf#123736 re-establish listeners for unshared formula groups

... when replacing one of their formula cells, with another
formula cell or any other cell, passing through
DetachFormulaCell()

Change-Id: Id527307ef5278d87345c6dbfab9d05cb490dfe6c
Reviewed-on: https://gerrit.libreoffice.org/69221Reviewed-by: Eike Rathke <erack@redhat.com>
Tested-by: Jenkins

sc/inc/column.hxx

@@ -636,8 +636,16 @@ public:
     /**
      * Detach a formula cell that's about to be deleted, or removed from
      * document storage (if that ever happens).
+     *
+     * @param rNewSharedRows collects possible new shared row ranges (top and
+     *        bottom of shared or remaining single twice) resulting from
+     *        unsharing to reestablish listeners on.
      */
-    void DetachFormulaCell( const sc::CellStoreType::position_type& aPos, ScFormulaCell& rCell );
+    void DetachFormulaCell( const sc::CellStoreType::position_type& aPos, ScFormulaCell& rCell,
+                            std::vector<SCROW>& rNewSharedRows );
+
+    /** Re-establish listeners on unshared formula groups */
+    void StartListeningUnshared( const std::vector<SCROW>& rNewSharedRows );
 
     void DetachFormulaCells( const sc::CellStoreType::position_type& aPos, size_t nLength );
 
@@ -692,15 +700,18 @@ public:
     bool        ReservePatternCount( SCSIZE nReserve );
 private:
 
-    sc::CellStoreType::iterator GetPositionToInsert( SCROW nRow );
-    sc::CellStoreType::iterator GetPositionToInsert( const sc::CellStoreType::iterator& it, SCROW nRow );
+    sc::CellStoreType::iterator GetPositionToInsert( SCROW nRow, std::vector<SCROW>& rNewSharedRows );
+    sc::CellStoreType::iterator GetPositionToInsert( const sc::CellStoreType::iterator& it, SCROW nRow,
+                                                     std::vector<SCROW>& rNewSharedRows );
 
     void AttachNewFormulaCell(
         const sc::CellStoreType::iterator& itPos, SCROW nRow, ScFormulaCell& rCell,
+        const std::vector<SCROW>& rNewSharedRows,
         bool bJoin = true, sc::StartListeningType eListenType = sc::SingleCellListening );
 
     void AttachNewFormulaCell(
         const sc::CellStoreType::position_type& aPos, ScFormulaCell& rCell,
+        const std::vector<SCROW>& rNewSharedRows,
         bool bJoin = true, sc::StartListeningType eListenType = sc::SingleCellListening );
 
     void AttachNewFormulaCells( const sc::CellStoreType::position_type& aPos, size_t nLength );

sc/source/core/tool/sharedformula.cxx

@@ -248,9 +248,9 @@ void SharedFormulaUtil::unshareFormulaCell(const CellStoreType::position_type& a
         {
             // Move the top cell to the next formula cell down.
             ScFormulaCell& rNext = *sc::formula_block::at(*it->data, aPos.second+1);
-            --xGroup->mnLength;
             xGroup->mpTopCell = &rNext;
         }
+        --xGroup->mnLength;
     }
     else if (rCell.aPos.Row() == rCell.GetSharedTopRow() + rCell.GetSharedLength() - 1)
     {