buffer: show control char visualizers in yellow

src/buffer/mod.rs

@@ -1605,6 +1605,7 @@ impl TextBuffer {
 
                 let mut global_off = cursor_beg.offset;
                 let mut cursor_tab = cursor_beg;
+                let mut cursor_visualizer = cursor_beg;
 
                 while global_off < cursor_end.offset {
                     let chunk = self.read_forward(global_off);
@@ -1654,6 +1655,25 @@ impl TextBuffer {
                             };
                             // Our manually constructed UTF8 is never going to be invalid. Trust.
                             line.push_str(unsafe { str::from_utf8_unchecked(&visualizer_buf) });
+
+                            cursor_visualizer = self.cursor_move_to_offset_internal(
+                                cursor_visualizer,
+                                global_off + chunk_off - 1,
+                            );
+                            let visualizer_rect = {
+                                let left = destination.left
+                                    + self.margin_width
+                                    + cursor_visualizer.visual_pos.x
+                                    - origin.x;
+                                let top =
+                                    destination.top + cursor_visualizer.visual_pos.y - origin.y;
+                                Rect { left, top, right: left + 1, bottom: top + 1 }
+                            };
+
+                            let bg = fb.indexed(IndexedColor::Yellow);
+                            let fg = fb.contrasted(bg);
+                            fb.blend_bg(visualizer_rect, bg);
+                            fb.blend_fg(visualizer_rect, fg);
                         }
                     }