anchor.diff:        editable,
         // The paint order is now flipped.
         paints
  -        ..rect(color: Colors.red[500], rect: Rect.fromLTWH(20, 2, 1, 6))
  +        ..rect(color: Colors.red[500])
           ..paragraph(),
       );
       expect(editable, paintsExactlyCountTimes(#drawRect, 1));
  
positive.code:       editable,
        paints
          ..paragraph()
          ..rect(color: Colors.red[500], rect: Rect.fromLTWH(20, 2, 1, 6)),
      );
  
      // There is exactly one rect paint (0 selection, 1 cursor).
  
negative.code:     expect(
        editable,
        paints
          // Check that it's the black selection box, not the red cursor.
          ..rect(color: Colors.black)
          ..paragraph(),
      );
  
  