我有兩個模型Article
和ArticleVote
。當我摧毀一篇文章投票(用戶取消他的投票)時,我想要改變文章的分數。所以我做了回調。這裏是我的ArticleVote模型是什麼樣子:ActiveRecord更改相關模型屬性
class ArticleVote < ActiveRecord::Base
belongs_to :article
belongs_to :user
before_destroy :before_destroy
validates :value, inclusion: {in: [1, -1]}
def self.upvote(user, article)
cast_vote(user, article, 1)
end
def self.downvote(user, article)
cast_vote(user, article, -1)
end
private
def self.cast_vote(user, article, value)
vote = ArticleVote.where(user_id: user.id, article_id: article.id).first_or_initialize
vote.value = value
vote.save!
article.score += value
article.save!
end
def before_destroy
article.score -= value
article.save
end
end
我ArticleVote#destroy
測試失敗:
context '#destroy' do
let(:user) { FactoryGirl.create(:user) }
let(:article) { FactoryGirl.create(:article) }
it 'changes article score by negative vote value' do
ArticleVote.upvote(user, article)
expect{ ArticleVote.where(user: user, article: article).first.destroy }.to change{ article.score }.by -1
end
end
Failures:
1) ArticleVote voting #destroy should change article score by nevative vote value Failure/Error: expect{ ArticleVote.where(user: user, article: article).first.destroy }.to change{ article.score }.by -1 result should have been changed by -1, but was changed by 0 # ./spec/models/article_vote_spec.rb:32:in `block (4 levels) in '
當我改變我的測試此,它通過:
context '#destroy' do
let(:user) { FactoryGirl.create(:user) }
let(:article) { FactoryGirl.create(:article) }
it 'changes article score by nevative vote value' do
ArticleVote.upvote(user, article)
vote = ArticleVote.where(user: user, article: article).first
expect{ vote.destroy }.to change{ vote.article.score }.by -1
end
end
不該這兩個是相等的嗎?我的article
和vote.article
不應該參考相同的實例?
什麼是第一次測試失敗時的輸出? – mralexlau
更新失敗 –