Got "found undefined tag" error on parsing prefab file of unity3d

Comienza con Psych.parse_stream y el Unity YAML proporcionado, especialmente con el límite del documento en la línea 21 y su directiva %TAG. Reproduce el Psych::SyntaxError y, a continuación, inspecciona cómo se gestionan las directivas y las etiquetas de múltiples documentos. Se considera terminado cuando el ejemplo se puede analizar mediante la API sin requerir preprocesamiento, con una prueba de regresión para la entrada proporcionada.

"found undefined tag handle while parsing a node at line 21 column 5 (Psych::SyntaxError)"
I got this error on parsing unity3d prefab file with parse_stream method.

Psych.parse_stream(yaml, filename: path) do |node|
       puts node
end

line 21 is " --- !u!224 &224286004637740336"
I can insert a new line "%TAG !u! tag:unity3d.com,2011: " before every "---" to fix it.

source.gsub(/^(?<!%TAG !u! tag:unity3d.com,2011:\n)^(--- !u![0-9]+ &[0-9]+)$/, "%TAG !u! tag:unity3d.com,2011:\n\\1")

But I hope there is a solution in API level.

%YAML 1.1
%TAG !u! tag:unity3d.com,2011:
--- !u!1 &1007462957078648
GameObject:
  m_ObjectHideFlags: 0
  m_CorrespondingSourceObject: {fileID: 0}
  m_PrefabInstance: {fileID: 0}
  m_PrefabAsset: {fileID: 0}
  serializedVersion: 6
  m_Component:
  - component: {fileID: 224286004637740336}
  - component: {fileID: 222770377023727128}
  - component: {fileID: 114746315234884256}
  m_Layer: 5
  m_Name: Icon
  m_TagString: Untagged
  m_Icon: {fileID: 0}
  m_NavMeshLayer: 0
  m_StaticEditorFlags: 0
  m_IsActive: 1
--- !u!224 &224286004637740336
RectTransform:
  m_ObjectHideFlags: 0
  m_CorrespondingSourceObject: {fileID: 0}
  m_PrefabInstance: {fileID: 0}
  m_PrefabAsset: {fileID: 0}
  m_GameObject: {fileID: 1007462957078648}
  m_LocalRotation: {x: -0, y: -0, z: -0, w: 1}
  m_LocalPosition: {x: 0, y: 0, z: -1.3}
  m_LocalScale: {x: 0.7, y: 0.7, z: 0.9996802}
  m_Children: []
  m_Father: {fileID: 224567198966254662}
  m_RootOrder: 0
  m_LocalEulerAnglesHint: {x: 0, y: 0, z: 0}
  m_AnchorMin: {x: 0.5, y: 0.5}
  m_AnchorMax: {x: 0.5, y: 0.5}
  m_AnchoredPosition: {x: 45.3, y: -79.2}
  m_SizeDelta: {x: 132, y: 132}
  m_Pivot: {x: 0.5, y: 0.5}