Question

我有跟踪推荐的Referral模型（即，当社交媒体网站上的用户生成唯一推荐/邀请链接并邀请其他人加入应用时）。

推荐呃 - 发出独特邀请链接的人
推荐 ee - 接收并使用该链接注册的人

我的模型和规格如下：

模型

# app/models/referral.rb

class Referral < ActiveRecord::Base
  # A referral has one user who refers and one user who is being referred. Both are User models.
  belongs_to :referrer, class_name: "User", foreign_key: "referrer_id"
  belongs_to :referree, class_name: "User", foreign_key: "referree_id"

  # Validate presence - don't allow nil
  validates :referrer_id, presence: true
  validates :referree_id, presence: true

  # Referrers can have multiple entries, must be unique to a referree, since they can 
  # only refer someone once. 
  # Referees can only BE referred once overall, so must be globally unique
  validates :referrer_id, uniqueness: { scope: :referree_id }
  validates :referree_id, uniqueness: true
end

规格

# spec/models/referral_spec.rb
require "spec_helper"

RSpec.describe Referral, type: :model do
  describe "Associations" do
    it { should belong_to(:referrer) }
    it { should belong_to(:referree) }
  end

  describe "Validations" do
    it { should validate_presence_of(:referrer_id) }
    it { should validate_presence_of(:referree_id) }

    it { should_not allow_value(nil).for(:referrer_id) }
    it { should_not allow_value(nil).for(:referree_id) }

    # These two FAIL
    it { should validate_uniqueness_of(:referrer_id).scoped_to(:referree_id) }
    it { should validate_uniqueness_of(:referree_id) }
  end
end

我的问题是最后两个规范测试总是失败，比如

1) Referral Validations should require case sensitive unique value for referrer_id scoped to referree_id
   Failure/Error: it { should validate_uniqueness_of(:referrer_id).scoped_to(:referree_id) }
   ActiveRecord::StatementInvalid:
     PG::NotNullViolation: ERROR:  null value in column "referree_id" violates not-null constraint
     DETAIL:  Failing row contains (1, 2016-01-13 19:28:15.552112, 2016-01-13 19:28:15.552112, 0, null).
     : INSERT INTO "referrals" ("referrer_id", "created_at", "updated_at") VALUES ($1, $2, $3) RETURNING "id"

看起来shoulda匹配器正在尝试在测试各种值时在其中插入nil值。使用allow_nil true和false进行游戏并未解决问题。

知道它为什么会在那里磕磕绊绊？

谢谢！

Answer 1

请参阅this

validate_uniqueness_of匹配器创建一个新实例（如果尚未存在）。这样做时，由于某些其他字段的模型验证，它可能会失败。在您的情况下，在验证referrer_id的唯一性时，referree_id中的值为nil，因此它失败。

解决方案是创建一个实例并为在列中抛出ERROR：null值的属性赋值。

再次，请参阅第一行中的链接以获取示例和详细说明

Shoulda Matchers试图在验证唯一性的同时插入“nil”值

1 个答案: