Testing before_create method in rspec and rails 3 - activerecord

Question

I've looked into some tutes and all I saw were old posts on how to test before_create. Also it seems like they're all just testing that before_create was called i.e.:
#user = User.new
#user.should_receive(:method_name_called_by_before_create)
#user.send(:before_create) (sometimes they just do #user.save)
I want to actually test that my method worked and that it had assigned(and saved the variables) after creating the record.
Here are my models:
user.rb
class User < ActiveRecord::Base
has_one :character, :dependent => :destroy
after_create :generate_character
private
def generate_character
self.create_character(:name => "#{email}'s avatar")
end
end
and character.rb
class Character < ActiveRecord::Base
belongs_to :user
before_create :generate_character
private
def generate_character
response = api_call
#API CALL HERE
#set object attributes here
self.stat1 = calculate_stat1(response) + 5
self.stat2 = calculate_stat2(response) + 5
self.stat3 = calculate_stat3(response) + 5
end
def api_call
return api_call_response
end
end
I want to test that generate character indeed set the attributes without going online and calling the API call. Is this possible with rspec? I have a fixture of a json response so I was hoping I can stub out generate character and then use the fake response for testing.
Here's my character.spec:
describe Character do
before(:each) do
Character.any_instance.stub!(:api_call).and_return(fake_response.read)
#user = Factory(:user)
#character = #user.character
puts #character.inspect
end
def fake_response
File.open("spec/fixtures/api_response.json")
end
It prints out only 5 for each of the character's stats. Also I did a puts response in the generate_character method in character.rb and it still prints out the "real" api call.
I managed to do a puts in fake_response and it does goes through there but it also goes through the "real" api_call after, which makes the stub obsolete. How do I get through this?

Answer 1

A good approach here is extracting your api call into a self contained method. Something like this:
class Character < ActiveRecord::Base
belongs_to :user
before_create :generate_character
private
def generate_character
data = api_call
#set object attributes from data
end
def api_call
# returns a data structure
# resulting from the call
end
end
Then use RSpec's any_instance to stub the api_call method to return a fixed data structure
Character.any_instance.stub!(:api_call).and_return { {:id => 1, :attribute_one => "foo"} }
#user = User.create
#user.character.attribute_one.should == "foo"
for more info on any_instance check this commit