Add User#customer_of to look up customers

app/models/customer.rb

@@ -1,7 +1,10 @@
 class Customer < ActiveRecord::Base
   belongs_to :enterprise
+  belongs_to :user, :class_name => Spree.user_class
 
   validates :code, presence: true, uniqueness: {scope: :enterprise_id}
   validates :email, presence: true
   validates :enterprise_id, presence: true
+
+  scope :of, ->(enterprise) { where(enterprise_id: enterprise) }
 end

app/models/spree/user_decorator.rb

@@ -4,6 +4,7 @@ Spree.user_class.class_eval do
   has_many :owned_enterprises, class_name: 'Enterprise', foreign_key: :owner_id, inverse_of: :owner
   has_many :owned_groups, class_name: 'EnterpriseGroup', foreign_key: :owner_id, inverse_of: :owner
   has_one :cart
+  has_many :customers
 
   accepts_nested_attributes_for :enterprise_roles, :allow_destroy => true
 
@@ -12,6 +13,7 @@ Spree.user_class.class_eval do
 
   validate :limit_owned_enterprises
 
+
   def known_users
     if admin?
       Spree::User.scoped
@@ -30,6 +32,10 @@ Spree.user_class.class_eval do
     end
   end
 
+  def customer_of(enterprise)
+    customers.of(enterprise).first
+  end
+
   def send_signup_confirmation
     Spree::UserMailer.signup_confirmation(self).deliver
   end
@@ -38,6 +44,7 @@ Spree.user_class.class_eval do
     owned_enterprises(:reload).size < enterprise_limit
   end
 
+
   private
 
   def limit_owned_enterprises

spec/factories.rb

@@ -203,6 +203,13 @@ FactoryGirl.define do
       create(:tax_rate, amount: proxy.tax_rate_amount, tax_category: product.tax_category, included_in_price: true, calculator: Spree::Calculator::DefaultTax.new, zone: proxy.zone)
     end
   end
+
+  factory :customer, :class => Customer do
+    email { Faker::Internet.email }
+    enterprise
+    code 'abc123'
+    user
+  end
 end
 
 

spec/models/spree/user_spec.rb

@@ -36,7 +36,14 @@ describe Spree.user_class do
         expect(u1.owned_groups(:reload)).to match_array([g1, g2])
         expect(u2.owned_groups(:reload)).to match_array([g3])
       end
+    end
 
+    it "loads a user's customer representation at a particular enterprise" do
+      u = create(:user)
+      e = create(:enterprise)
+      c = create(:customer, user: u, enterprise: e)
+
+      u.customer_of(e).should == c
     end
   end