如何测试自定义验证器？

Question

我有以下验证器:

# Source: http://guides.rubyonrails.org/active_record_validations_callbacks.html#custom-validators
# app/validators/email_validator.rb

class EmailValidator < ActiveModel::EachValidator
  def validate_each(object, attribute, value)
    unless value =~ /^([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})$/i
      object.errors[attribute] << (options[:message] || "is not formatted properly") 
    end
  end
end

我希望能够在我的lib目录中的RSpec中测试它.到目前为止的问题是我不知道如何初始化EachValidator.

Answer 1

我不是其他方法的忠实粉丝,因为它将测试与实现联系得太紧密了.此外,它很难遵循.这是我最终使用的方法.请记住,这是对我的验证员实际做了什么的粗略过度简化...只是想更简单地证明它.肯定会有优化

class OmniauthValidator < ActiveModel::Validator
  def validate(record)
    if !record.omniauth_provider.nil? && !%w(facebook github).include?(record.omniauth_provider)
      record.errors[:omniauth_provider] << 'Invalid omniauth provider'
    end
  end
end

相关规范:

require 'spec_helper'

class Validatable
  include ActiveModel::Validations
  validates_with OmniauthValidator
  attr_accessor  :omniauth_provider
end

describe OmniauthValidator do
  subject { Validatable.new }

  context 'without provider' do
    it 'is valid' do
      expect(subject).to be_valid
    end
  end

  context 'with valid provider' do
    it 'is valid' do
      subject.stubs(omniauth_provider: 'facebook')

      expect(subject).to be_valid
    end
  end

  context 'with unused provider' do
    it 'is invalid' do
      subject.stubs(omniauth_provider: 'twitter')

      expect(subject).not_to be_valid
      expect(subject).to have(1).error_on(:omniauth_provider)
    end
  end
end

基本上我的方法是创建一个虚假对象"Validatable",这样我们就可以在其上实际测试结果,而不是对实现的每个部分都有期望

Answer 2

这是一个快速的规范,我敲了那个文件,它运作良好.我认为存根可能会被清除,但希望这足以让你开始.

require 'spec_helper'


describe "EmailValidator" do

  before(:each) do
    @validator = EmailValidator.new({:attributes => {}})
    @mock = mock('model')
    @mock.stub("errors").and_return([])
    @mock.errors.stub('[]').and_return({})  
    @mock.errors[].stub('<<')
  end

  it "should validate valid address" do
    @mock.should_not_receive('errors')    
    @validator.validate_each(@mock, "email", "test@test.com")
  end

  it "should validate invalid address" do
    @mock.errors[].should_receive('<<')
    @validator.validate_each(@mock, "email", "notvalid")
  end  
end

Answer 3

我建议为测试目的创建一个匿名类，例如：

require 'spec_helper'
require 'active_model'
require 'email_validator'

RSpec.describe EmailValidator do
  subject do
    Class.new do
      include ActiveModel::Validations    
      attr_accessor :email
      validates :email, email: true
    end.new
  end

  describe 'empty email addresses' do
    ['', nil].each do |email_address|
      describe "when email address is #{email_address}" do
        it "does not add an error" do
          subject.email = email_address
          subject.validate
          expect(subject.errors[:email]).not_to include 'is not a valid email address'
        end
      end
    end
  end

  describe 'invalid email addresses' do
    ['nope', '@', 'foo@bar.com.', '.', ' '].each do |email_address|
      describe "when email address is #{email_address}" do

        it "adds an error" do
          subject.email = email_address
          subject.validate
          expect(subject.errors[:email]).to include 'is not a valid email address'
        end
      end
    end
  end

  describe 'valid email addresses' do
    ['foo@bar.com', 'foo@bar.bar.co'].each do |email_address|
      describe "when email address is #{email_address}" do
        it "does not add an error" do
          subject.email = email_address
          subject.validate
          expect(subject.errors[:email]).not_to include 'is not a valid email address'
        end
      end
    end
  end
end

这样可以防止Validatable在多个规范中引用诸如之类的硬编码类，由于不相关的验证之间存在交互，您将尝试进行单独的测试，从而导致意外的行为和难以调试的行为。

Answer 4

受到@Gazler 回答的启发，我想出了以下内容；嘲笑模型，但ActiveModel::Errors用作错误对象。这大大减少了嘲笑。

require 'spec_helper'

RSpec.describe EmailValidator, type: :validator do
  subject { EmailValidator.new(attributes: { any: true }) }

  describe '#validate_each' do
    let(:errors) { ActiveModel::Errors.new(OpenStruct.new) }
    let(:record) {
      instance_double(ActiveModel::Validations, errors: errors)
    }

    context 'valid email' do
      it 'does not increase error count' do
        expect {
          subject.validate_each(record, :email, 'test@example.com')
        }.to_not change(errors, :count)
      end
    end

    context 'invalid email' do
      it 'increases the error count' do
        expect {
          subject.validate_each(record, :email, 'fakeemail')
        }.to change(errors, :count)
      end

      it 'has the correct error message' do
        expect {
          subject.validate_each(record, :email, 'fakeemail')
        }.to change { errors.first }.to [:email, 'is not an email']
      end
    end
  end
end