Meaning for attributes_for in FactoryGirl and Rspec Testing
attributes, factory-bot, rspec, ruby-on-rails, ruby-on-rails-3
Solution
`attributes_for` will return a hash, whereas `build` will return a non persisted object.
Given the following factory:
FactoryGirl.define do
factory :user do
name 'John Doe'
end
end
Here is the result of `build`:
FactoryGirl.build :user
=> #<User id: nil, name: "John Doe", created_at: nil, updated_at: nil>
and the result of `attributes_for`
FactoryGirl.attributes_for :user
=> {:name=>"John Doe"}
I find `attributes_for` very helpful for my functional test, as I can do things like the following to create a user:
post :create, user: FactoryGirl.attributes_for(:user)
When using `build`, we would have to manually create a hash of attributes from the `user` instance and pass it to the `post` method, such as:
u = FactoryGirl.build :user
post :create, user: u.attributes # This is actually different as it includes all the attributes, in that case updated_at & created_at
I usually use `build` & `create` when I directly want objects and not an attributes hash
Let me know if you need more details
Problem
Looking through a tutorial on controller testing the author gives an example of an rspec test testing a controller action. My question is, why did they use the method `attributes_for` over `build`? There is no clear explanation why `attributes_for` is used besides that it returns a hash of values. ``` it "redirects to the home page upon save" do post :create, contact: Factory.attributes_for(:contact) response.should redirect_to root_url end ``` The tutorial link is found here: http://everydayrails.com/2012/04/07/testing-series-rspec-controllers.html The example is found at the beginning topic section `Controller testing basics`