UnityEditor.Graphs.Edge.WakeUp () (at ＜XXX＞:0)

Unity报错：
UnityEditor.Graphs.Edge.WakeUp () (at :0)

错误状况：
代码正确，但运行时总是报错：
NullReferenceException: Object reference not set to an instance of an object
UnityEditor.Graphs.Edge.WakeUp () (at :0)
UnityEditor.Graphs.Graph.DoWakeUpEdges (System.Collections.Generic.List1[T] inEdges, System.Collections.Generic.List1[T] ok, System.Collections.Generic.List`1[T] error, System.Boolean inEdgesUsedToBeValid) (at :0)
UnityEditor.Graphs.Graph.WakeUpEdges (System.Boolean clearSlotEdges) (at :0)
UnityEditor.Graphs.Graph.WakeUp (System.Boolean force) (at :0)
UnityEditor.Graphs.Graph.WakeUp () (at :0)
UnityEditor.Graphs.Graph.OnEnable () (at :0)

最后通过搜索，解决方法竟然是：
重启…我服了