使用 rspec + shoulda-matchers 进行测试

Question

我以前从未写过自己的测试，我刚刚完成模型关联并迁移它们，所以现在我想测试它们。我已经添加到 gemfile 并在 group :test 下安装了 gem 'shoulda-matchers', '~> 3.0'，在 group :development, :test 下安装了 gem 'rspec-rails', '~> 3.0'。将 shoulda-matchers 的配置添加到 spec/rails_helper.rb 中。下一步是什么？测试文件将放入哪个目录？编写 shoulda 匹配器的句法规则是什么，与 rspec 相同？例如，我如何检查该关联是否正常工作？

class Artist < ApplicationRecord
  has_many events, :through => :lineups
end

像这样？

describe Artist do
  it { should have_many(:events).through(:lineups) }
end

Answer 1

我觉得不错 - 这是另一个使用 class Listing 测试关联和验证的示例。

class Listing < ActiveRecord::Base

  #Associations
  belongs_to :user
  belongs_to :category, inverse_of: :listings
  has_many :photos, dependent: :destroy 
  has_many :watches
  has_many :watchers, -> { uniq }, :through => :watches
  has_many :offers, dependent: :destroy
  has_many :feedbacks
  belongs_to :location, :dependent => :destroy

  # Association validations
  validates_presence_of :category
  validates_presence_of :user

  # Attribute validations
  validates_presence_of :title, message: "Please add a title."
  validates_presence_of :subtitle, message: "Please add a subtitle."
  validates_presence_of :price, message: "Please add a price."
  validates_presence_of :title, message: "Please select a condition."

require 'rails_helper'

RSpec.describe Listing, type: :model do

  #Associations
  it { should belong_to(:user) }
  it { should belong_to(:category) }
  it { should have_many(:photos) }
  it { should have_many(:watches) }
  it { should have_many(:watchers).through(:watches) }
  it { should have_many(:offers) }
  it { should belong_to(:location).dependent(:destroy) }

  #Association validations
  it { should validate_presence_of(:category) }
  it { should validate_presence_of(:user) }

  #Attribute validations
  it { should validate_presence_of(:title).with_message("Please add a title.") }
  it { should validate_presence_of(:subtitle).with_message("Please add a subtitle.") }
  it { should validate_presence_of(:price).with_message("Please add a price.") }
  it { should validate_presence_of(:title).with_message("Please select a condition.") }

注意使用 RSpec.describe Class, type: :model 指定测试类型。

我会阅读 Shoulda 自述文件，其中详细解释了各种示例组中匹配器的可用性。他们提供四类匹配器：

ActiveRecord and ActiveModel matchers are available only in model example groups, i.e., those tagged with type: :model or in files located under spec/models.

ActionController matchers are available only in controller example groups, i.e., those tagged with type: :controller or in files located under spec/controllers.

The route matcher is available also in routing example groups, i.e., those tagged with type: :routing or in files located under spec/routing.

Independent matchers are available in all example groups.

在安排您的规格方面旨在镜像您的应用程序目录（或多或少）。

所以如果你有：

app/models/user.rb
app/services/
app/controllers/
app/presenters/

您可以通过以下方式进行镜像：

spec/models/user_spec.rb
spec/services/
spec/controllers/
spec/presenters/

您可能会有一些额外的规范文件夹，例如：

spec/features/ (a folder for integration/feature specs)

RSpec 文档对此有一些很好的信息。

使用 rspec + shoulda-matchers 进行测试

testing with rspec + shoulda-matchers

rspec

ruby-on-rails

shoulda