更新

app/models/hack.rb

@@ -16,7 +16,7 @@ class Hack < ApplicationRecord
   # 消息
   has_many :tidings, as: :container
   # 知识点
-  has_many :tag_discipline_containers, dependent: :destroy
+  has_many :tag_discipline_containers, as: :container, dependent: :destroy
 
   belongs_to :user
   belongs_to :sub_discipline