Warp all cursors at/after the insert point when inserting a code point

src/core/Buffer.cc

@@ -169,6 +169,14 @@ void Buffer::insert_code_point(uint32_t code_point)
         uint8_t encoded[Encoding::MAX_CODE_POINT_SIZE];
         uint8_t bytes = Encoding::encode(code_point, m_encoding, encoded);
         m_gap_buffer->insert(m_insert_position, encoded, bytes);
+        ssize_t lines = (code_point == '\n') ? 1 : 0;
+        for (auto iterator : m_iterators)
+        {
+            if (iterator->offset() >= m_insert_position)
+            {
+                iterator->warp(bytes, lines);
+            }
+        }
         m_insert_position += bytes;
     }
 }

src/core/Buffer.h

@@ -93,7 +93,9 @@ public:
 
     std::shared_ptr<Iterator> add_iterator()
     {
-        return std::make_shared<Iterator>(this);
+        std::shared_ptr<Iterator> iterator = std::make_shared<Iterator>(this);
+        m_iterators.push_back(iterator);
+        return iterator;
     }
     auto get_string() { return m_gap_buffer->get_string(); }
     size_t size() const { return m_gap_buffer->size(); }
@@ -113,6 +115,7 @@ protected:
     uint8_t m_tabstop;
     bool m_insert_mode;
     size_t m_insert_position;
+    std::list<std::shared_ptr<Iterator>> m_iterators;
 
     void common_initialization();
     bool load_from_file(const char * filename);