使用FactoryGirl的has_many关系

# 定义模型对象
class User < ActiveRecord::Base
  has_many :posts
end

class Post < ActiveRecord::Base
  belongs_to :user
end

# 使用FactoryGirl创建模型对象
FactoryGirl.define do
  factory :user do
    name "John Doe"
    
    # 使用trait定义has_many关系
    trait :with_posts do
      after(:create) do |user|
        create_list(:post, 3, user: user)
      end
    end
  end
  
  factory :post do
    title "Hello World"
    content "This is a test post"
    user
  end
end

# 在测试中使用FactoryGirl创建具有has_many关系的模型对象
RSpec.describe User, type: :model do
  it "has many posts" do
    user = create(:user, :with_posts)
    expect(user.posts.count).to eq(3)
  end
end