TableRef: generate error for header-less column references, tdf#91278 related

... instead of using an arbitray first data record's string as column
name. We don't support header-less tables properly yet, so don't pretend
to.

Change-Id: Ia42619ec800291b6617a61c8a89a2d54ef231cec

sc/source/core/tool/compiler.cxx

@@ -3517,6 +3517,8 @@ bool ScCompiler::IsTableRefColumn( const OUString& rName ) const
     aRange.aEnd.SetTab( aRange.aStart.Tab());
     aRange.aEnd.SetRow( aRange.aStart.Row());
 
+    if (pDBData->HasHeader())
+    {
         // Quite similar to IsColRowName() but limited to one row of headers.
         ScCellIterator aIter( pDoc, aRange);
         for (bool bHas = aIter.first(); bHas; bHas = aIter.next())
@@ -3549,6 +3551,7 @@ bool ScCompiler::IsTableRefColumn( const OUString& rName ) const
                 }
             }
         }
+    }
 
     // And now a fallback for named expressions during document load time when
     // cell content isn't available yet. This could be the preferred method IF
@@ -3556,12 +3559,27 @@ bool ScCompiler::IsTableRefColumn( const OUString& rName ) const
     // operations, including cell content changes.
     sal_Int32 nOffset = pDBData->GetColumnNameOffset( aName);
     if (nOffset >= 0)
+    {
+        if (pDBData->HasHeader())
         {
             ScSingleRefData aRef;
             ScAddress aAdr( aRange.aStart);
             aAdr.IncCol( nOffset);
             aRef.InitAddress( aAdr);
             maRawToken.SetSingleReference( aRef );
+        }
+        else
+        {
+            /* TODO: this probably needs a new token type to hold offset and
+             * name, to be handled in HandleTableRef(). We can't use a
+             * reference token here because any reference would be wrong as
+             * there are no header cells to be referenced. However, it would
+             * only work as long as the ScDBData column names are not
+             * invalidated during document structure changes, otherwise
+             * recompiling the same formula could not resolve the name again.
+             * As long as this doesn't work generate an error. */
+            return false;
+        }
         return true;
     }