rspec - Rails 5 before_destroy 抛出(:abort)

Question

我正在使用旧版 Rails 应用程序，该应用程序已随 Rails 的每个主要版本进行了认真升级，我们目前使用的是 Rails 5.1，但我无法获得 before_destroy如果验证失败，则防止删除

我一直在读return false已被弃用，我们都应该使用 throw :abort但两者都不起作用。我没有收到任何错误，尽管存在 throw，但连接记录却被删除了

用户.rb:

class User < ApplicationRecord
  has_many :permission_users
  has_many :permissions, through: :permission_users, dependent: :destroy
end

加入模型permission_user.rb:

class PermissionUser < ApplicationRecord
  belongs_to :user
  belongs_to :permission

  before_destroy :check_before_removing!

  private

  def check_before_removing!
    if not_valid? # condition isn't important
      errors.add :base, exception.message
      throw(:abort)
    end
  end
end

我的规范:

specify "cannot have their admin permissions revoked" do
  expect {
    admin.permissions.delete admin_permission
  }.to change { admin.permissions.count }.by(0)       
end

# => expected `admin.permissions.count` to have changed by 0, but was changed by -1

Answer 1

有a catch with this callback :

before_destroy callbacks should be placed before dependent: :destroy associations (or use the prepend: true option), to ensure they execute before the records are deleted by dependent: :destroy.

所以请尝试

before_destroy :check_before_removing!, prepend: true