Custom scope not returning any results - ruby-on-rails

Question

Basic association setup (note, Customer is an extension of a Person model):
Customer has_many :orders
Order belongs_to :customer
Inside of Customer.rb, I have the following class method:
# SCOPE
def self.ordered_in_90_days
joins(:orders).where('orders.created_at > ?', 90.days.ago)
end
In my test, I have the following code which creates a new Order (automatically creating a customer thanks for FactoryGirl), then uses the Customer model's self method defined above:
it "finds customers who have ordered within the last 90 days" do
#order = FactoryGirl.create(:order, created_at: 50.days.ago)
#customer = #order.customer
Customer.count.should == 1 #passes
Order.count.should == 1 #passes
puts Customer.all.to_yaml #for debugging, see below
puts Order.all.to_yaml #for debugging, see below
Customer.ordered_in_90_days.should == [#customer] #fails! returns: []
end
Both the customer and order are being created, but nothing is returning in the method call (empty array). What am I missing?
Here is some additional information regarding the factories:
FactoryGirl.define do
factory :customer do
first_name "Wes"
last_name "Foster"
type "Customer"
end
factory :order do
customer
end
end
And here is the debugging output for Customer and Order (remember, Customer is an extension of Person, so that's why you see person_id instead of customer_id):
---
- !ruby/object:Customer
attributes:
id: 1
first_name: Wes
last_name: Foster
type: Customer
created_at: 2013-09-16 21:54:26.162851000 Z
updated_at: 2013-09-16 21:54:26.162851000 Z
middle_name:
---
- !ruby/object:Order
attributes:
id: 1
person_id:
created_at: 2013-07-28 21:54:26.135748000 Z
updated_at: 2013-09-16 21:54:26.192877000 Z
(Customer

Answer 1

The debug output indicates the problem, indeed! Take a look at the Order inspect: you have person_id blank.
First, even if a Customer is a subclass/extension of Person, the Order belongs_to :customer tells ActiveRecord to look for customer_id, not person_id. Are you indicating that the association should be configured in a non-default way on the Order model?
Otherwise, I think you might be mishandling the aliased association reference in the Order factory. I've not used factory_girl association alias references in my project—I try to keep associations out of my factories—but I would verify your methodology with the factory_girl documentation: Association Aliases.
I would, personally, try this in your test example:
it "finds customers who have ordered within the last 90 days" do
#customer = FactoryGirl.create(:customer)
#order = FactoryGirl.create(:order, created_at: 50.days.ago, customer: #customer)
Customer.count.should == 1
Order.count.should == 1
Customer.ordered_in_90_days.should == [#customer]
end
Setting the #order.customer explicitly in your examples allows you to eliminate the factory dependency and complexity.
Sidenote
If you want to keep the association alias method in your factory, and rely on that association in other tests, I would suggest writing a separate test to verify that factory relationship instantiating correctly:
#order = create(:order)
expect(#order.customer).to be_a(Customer)
Or something like that...