建立bot

官方文件有說有以下建立方式至於差別在哪呢？

# Returns a User instance that's not saved
user = build(:user)

# Returns a saved User instance
user = create(:user)

# Returns a hash of attributes that can be used to build a User instance
attrs = attributes_for(:user) # {name: 'CK', phone: '123'}

# Returns an object with all defined attributes stubbed out
stub = build_stubbed(:user)

# Passing a block to any of the methods above will yield the return object
create(:user) do |user|
  user.posts.create(attributes_for(:post))
end

create => 真的寫進db

build => 還沒save 且 id為 nil

build_stubbed => stub 的概念創建一個假的實體而且還有 id

attributes_for => 拿到 FactoryBot 的 attribute

我平常使用起來，如果你建立的資料能不進就不進！速度會快上很多！

因為有時候建立資料的時候關聯的問題可能你只需要測試 profile 但一定要有 user，這時候 user 就可以用 build_stubbed，既能拿到資料也能不會進db commit！

如果還是不懂build、create、build_stubbed的可以看看這篇
FactoryGirl create vs build vs build_stubbed
attributes_for