Question

我希望找出是否可以使用瞬态值更新对象属性，我有这个测试

it 'should be able to update an image category' do
  @image = FactoryGirl.create(:image, categories_count: 2)
  expect(@image.image_categories.count).to eq(2)
  @image.update_attributes(categories_count: 1)
  @image.save
  expect(@image.image_categories.count).to eq(1)
end

FactoryGirl.define do
  factory :image do
    title 'Test Title'
    description 'Test Description'
    transient do
      photo_name 'validated_image.jpg'
    end
    photo { File.new(File.join(Rails.root, 'spec/fixtures', photo_name)) }
    transient do
      categories_count 1
    end
    categories { build_list(:category, categories_count) }
  end
end

但它失败了

ActiveRecord::UnknownAttributeError:
unknown attribute 'categories_count' for Image.

如何更新@image

的categories_count

模式

create_table "images", force: :cascade do |t|
  t.string   "title"
  t.text     "description"
  t.string   "photo_file_name"
  t.string   "photo_content_type"
  t.integer  "photo_file_size"
  t.datetime "photo_updated_at"
  t.datetime "created_at",         null: false
  t.datetime "updated_at",         null: false
end

create_table "categories", force: :cascade do |t|
  t.string   "name"
  t.datetime "created_at", null: false
  t.datetime "updated_at", null: false
end

create_table "image_categories", force: :cascade do |t|
  t.integer  "image_id"
  t.integer  "category_id"
  t.datetime "created_at",  null: false
  t.datetime "updated_at",  null: false
end

模型

class Image < ActiveRecord::Base
  has_many :image_categories, dependent: :destroy
  has_many :categories, through: :image_categories
  has_attached_file :photo,
                styles: {
                  image_square_home: '350x350#',
                  image_thumb: '100x100#'
                }
  validates_attachment :photo, content_type: { :content_type => ['image/jpg', 'image/jpeg', 'image/gif', 'image/png'], message: 'Images must be jpg/jpeg/gif/png format only' },
                           size: { in: 0..2000.kilobytes, message: 'Images should be less than 2 megabytes' }
  validates :title, presence: { message: "Don't forget to add a title" }
  validates :description, presence: { message: "Don't forget to add a description" }
  validates :categories, presence: { message: 'Choose At Least 1 Category' }
end

class Category < ActiveRecord::Base
  has_many :image_categories
  has_many :images, through: :image_categories
  validates :name, presence: { message: "Don't forget to add a Category" }
  validates_uniqueness_of :name, message: 'Category name %{value} already exists'
  validates_format_of :name, with: /\A([A-Za-z]+ )+[A-Za-z]+$|^[A-Za-z]+\z/, message: 'Only A-Z Characters Allowed', allow_blank: true, allow_nil: true
end

运行测试时，我得到以下输出

 Failure/Error: @image.update_attributes(categories_count: 1)

 ActiveRecord::UnknownAttributeError:
   unknown attribute 'categories_count' for Image.
 # ./spec/models/image_spec.rb:71:in `block (4 levels) in <top (required)>'
 # ------------------
 # --- Caused by: ---
 # NoMethodError:
 #   undefined method `categories_count=' for #<Image:0x00000005483550>
 #   ./spec/models/image_spec.rb:71:in `block (4 levels) in <top (required)>'

Answer 1

一直在寻找错误的路线。你的工厂很好，你以正确的方式使用它。 Factory返回一个ActiveRecord对象，该对象不知道它是如何创建的，并且完全不知道它的工厂是如何生成的：

@image.update_attributes(categories_count: 1)

update_attributes对记录本身采取行动，该记录本身不知道categories_count。目前还不清楚你想要发生什么，或者你正在测试的是你正在测试FactoryGirl而不是你的模型。

具有瞬态Rspec / FactoryGirl的update_attributes

1 个答案: