允许first_name或last_name为null但不能同时为null的验证

Question

class Profile < ApplicationRecord
  belongs_to :user
  validate :first_or_last_name_null


  def first_or_last_name_null
    if first_name.nil? && last_name.nil?
        errors.add(:base, "either first_name or last_name must be present!")
    end
  end

我不知道我的代码行有什么问题，无法从rspec中获得以下错误。分配rq11验证器：当姓氏存在时，允许个人资料的名字为空失败/错误：期望（Profile.new（：first_name => nil，：last_name =>“ Smith”，：gender =>“ male”））。be_valid预期#<Profile id: nil, gender: "male", birth_year: nil, first_name: nil, last_name: "Smith", user_id: nil, created_at: nil, updated_at: nil>.valid?返回true，得到false

规格文件具有以下..

context "rq11" do
      context "Validators:" do
        it "does not allow a User without a username" do
          expect(User.new(:username=> "")).to_not be_valid
        end

        it "does not allow a Profile with a null first and last name" do
          expect(Profile.new(:first_name=>nil, :last_name=>nil, :gender=>"male")).to_not be_valid
        end
        it "allows a Profile with a null first name when last name present" do
          expect(Profile.new(:first_name=>nil, :last_name=>"Smith", :gender=>"male")).to be_valid
        end
        it "allows a Profile with a null last name when first name present" do
          expect(Profile.new(:first_name=>"Joe", :last_name=>nil, :gender=>"male")).to be_valid
        end

        it "does not allow a Profile with a gender other than male or female " do
          expect(Profile.new(:first_name=>"first", :last_name=>"last", :gender=>"neutral")).to_not be_valid
        end
        it "does not allow a boy named Sue" do
          expect(Profile.new(:first_name=>"Sue", :last_name=>"last", :gender=>"male")).to_not be_valid
        end
        it "allows a Profile with gender male" do
          expect(Profile.new(:first_name=>"first", :last_name=>"last", :gender=>"male")).to be_valid
        end
        it "allows a Profile with gender female" do
          expect(Profile.new(:first_name=>"first", :last_name=>"last", :gender=>"female")).to be_valid
        end
      end
    end

Answer 1

我认为这是无效的，因为user_id为空。我记得默认情况下，rails会验证关联的存在。将user_id添加到所有配置文件中，应该没问题

Answer 2

虽然罗曼的答案是正确的，但我想添加更多详细信息和更多选项来解决问题。

您的Profile belong_to :user。默认情况下，belongs_to关联要求关联的对象存在。在这种情况下，必须有一个用户与配置文件相关联，否则该配置文件将无效。

根据您的用例，您可以通过三种选择来解决此问题：

1. 使关联为可选，请阅读有关optional belongs_to associations in the Rails Guides。如果在您的应用程序上下文中有必要不需要始终存在关联，则这显然只是一个选择。

   belongs_to

   belongs_to :user, optional: true 禁用内置验证。

2. 您要确保规范中的每个配置文件始终分配有有效的用户。这样的事情可能会起作用：

   optional: true

3. 您不仅测试实例是否有效，而且还测试是否存在预期的特定错误

   let(:user) { User.find_or_create_by(username: 'test_user') }
   
   it "does not allow a Profile with a null first and last name" do
     expect(Profile.new(user: user, first_name: nil, last_name: nil, gender: "male")).to_not be_valid
   end