re-calculate cursor column for all cursors on any insertion

src/core/PieceTable.cc

@@ -497,6 +497,11 @@ void PieceTable::insert_code_point(uint32_t code_point)
         uint8_t bytes = Encoding::encode(code_point, encoding, &m_append_buffer[m_append_buffer_index]);
         m_inserting_piece->length += bytes;
         m_append_buffer_index += bytes;
+
+        for (auto cursor : m_cursors)
+        {
+            cursor->calculate_column();
+        }
     }
 }
 

src/core/PieceTable.h

@@ -135,6 +135,7 @@ public:
         }
         void warp_to_inserted_piece(Piece * piece);
         void warp_to_beginning_of_piece(Piece * piece);
+        void calculate_column();
 
     protected:
         bool is_start_of_line();
@@ -142,7 +143,6 @@ public:
         Piece * prev_line() const;
         Piece * next_line() const;
         void init_column();
-        void calculate_column();
         void forward_to_column(uint32_t c);
     };