pub(all) struct PaintLayoutShift {
  node_path : String
  node_id : String
  dx : Double
  dy : Double
  dw : Double
  dh : Double
}

pub(all) struct PaintPropertyChange {
  node_path : String
  node_id : String
  property : String
  before : String?
  after : String?
}

pub(all) struct PaintTreeDiff {
  changes : Array[PaintPropertyChange]
  layout_shifts : Array[PaintLayoutShift]
}

fn diff_trees(before : 
@mizchi/crater-painter/paint/model.PaintNode
PaintNode, after : 
@mizchi/crater-painter/paint/model.PaintNode
PaintNode) -> PaintTreeDiff