Rspec的 - 檔案陣列進行匹配測試陣列

Question

我在爲獲得檔案

def self.archives 
    Post.unscoped.select("YEAR(created_at) AS year, MONTHNAME(created_at) AS month, COUNT(id) AS total") 
     .group("year, month, MONTH(created_at)") 
     .order("year DESC, MONTH(created_at) DESC") 
end 

這是測試我有我的方法寫

context '.archives' do 

    first = FactoryGirl.create(:post, published_at: Time.zone.now) 
    second = FactoryGirl.create(:post, published_at: 1.month.ago) 

    it 'returns articles archived' do 
    archives = Post.archives() 

    expect(
     [{ 
     year: first.published_at.strftime("%Y"), 
     month: first.published_at.strftime("%B"), 
     published: 1 
     }, 
     { 
     year: second.published_at.strftime("%Y"), 
     month: second.published_at.strftime("%B"), 
     published: 1 
     }] 
    ).to match_array(archives) 
    end 
end 

但是在我的崗位模型該類方法我得到以下錯誤

expected collection contained: [#<Post id: nil>, #<Post id: nil>] 
actual collection contained: [{:year=>"2017", :month=>"October", :published=>1}, {:year=>"2017", :month=>"September", :total=>1}] 
the missing elements were:  [#<Post id: nil>, #<Post id: nil>] 
the extra elements were:  [{:year=>"2017", :month=>"October", :total=>1}, {:year=>"2017", :month=>"September", :total=>1}] 

所以，雖然我創建了2個工廠，但archives數組是空。我究竟做錯了什麼？

Answer 1

Rspec的標準是使用let語法的上下文中定義的變量或描述塊。測試應該是這個樣子：

describe '.archives' do 
    let!(:first) { FactoryGirl.create(:post, published_at: Time.zone.now) } 
    let!(:second) { FactoryGirl.create(:post, published_at: 1.month.ago) } 

    it 'returns year, month, and total for articles archived' do 
    actual_attributes = Post.archives.map { |post| [post.year, post.month, post.total] } 
    expected_total = 1 # I don't know why the query is returning 1 for total, but including this for completeness 
    expected_attributes = [first, second].map { |post| [post.created_at.year, post.created_at.strftime("%B"), expected_total] } 

    expect(actual_attributes).to match_array(expected_attributes) 
    end 
end 

這裏的問題是，你比較，只有少數屬性（您的SQL查詢的結果）具有完全形成的記錄（通過測試創建）拉記錄。該測試從兩個組中拉取適用的屬性並進行比較。

Answer 2

實際數組不是空的，它是兩個Post實例的id未設置的數組（因爲Select的.archives方法不包含id字段）。 您可以比較預期的哈希值不archives，但水木清華這樣的：

actual = Post.archives().map do |post| 
    { year: post["year"].to_s, month: post["month"], published: post["total"] } 
end 

expected = [{ 
    year: first.published_at.strftime("%Y").to_s, 
    month: first.published_at.strftime("%B"), 
    published: 1 
}, 
{ 
    year: second.published_at.strftime("%Y").to_s, 
    month: second.published_at.strftime("%B"), 
    published: 1 
}] 

expect(actual).to match_array(expected)