Jump to line number for :<n> commands

src/core/BufferView.cc

@@ -229,6 +229,42 @@ bool BufferView::cursor_move(CursorMovement which, uint32_t c, bool allow_eol)
     return moved;
 }
 
+bool BufferView::cursor_move_to_line(size_t target_line)
+{
+    size_t current_line = m_iterator->line();
+    std::shared_ptr<Buffer::Iterator> it;
+    if (target_line <= current_line / 2u)
+    {
+        it = m_buffer->beginp();
+    }
+    else if (target_line <= ((current_line + m_buffer->end().line()) / 2u))
+    {
+        it = m_iterator->clonep();
+    }
+    else
+    {
+        it = m_buffer->endp();
+        it->go_back();
+        it->go_start_of_line();
+    }
+    while (it->line() < target_line)
+    {
+        if (!it->go_next_line())
+            break;
+    }
+    while (it->line() > target_line)
+    {
+        if (!it->go_previous_line())
+            break;
+    }
+    if (current_line != it->line())
+    {
+        *m_iterator = *it;
+        return true;
+    }
+    return false;
+}
+
 void BufferView::scroll_view_up(int n_lines, bool allow_eol)
 {
     int orig_cursor_screen_row = m_cursor_screen_row;

src/core/BufferView.h

@@ -83,6 +83,7 @@ public:
         return BufferLineWalker(m_buffer, start_of_line, m_width, m_character_width_determiner);
     }
     bool cursor_move(CursorMovement which, uint32_t c, bool allow_eol);
+    bool cursor_move_to_line(size_t line);
     int cursor_screen_row() const { return m_cursor_screen_row; }
     int cursor_screen_column() const { return m_cursor_screen_column; }
     int cursor_virtual_column() const { return m_cursor_virtual_column; }