如何验证 Mongoid 中的数组不为空?

How to validate that an array is not empty in Mongoid?

class Foo
  include Mongoid::Document

  field :bars, type:Array
end

如何验证 bars 数组不为空?

尝试标准 presence 验证器:

class Foo
  include Mongoid::Document

  field :bars, type: Array

  validates :bars, presence: true
end

这是有效的,因为 presence 验证器在验证期间使用 blank? 方法检查属性。