Allow removing customer codes

app/assets/javascripts/admin/customers/controllers/customers_controller.js.coffee

@@ -14,11 +14,13 @@ angular.module("admin.customers").controller "customersCtrl", ($scope, $q, Custo
         $scope.customers = data
 
   $scope.checkForDuplicateCodes = ->
-    customers = $scope.findByCode(this.customer.code)
-    if (customers.length > 1)
-      this.duplicate = true
-    else
-      this.duplicate = false
+    delete this.customer.code unless this.customer.code
+    this.duplicate = $scope.isDuplicateCode(this.customer.code)
+
+  $scope.isDuplicateCode = (code) ->
+    return false unless code
+    customers = $scope.findByCode(code)
+    customers.length > 1
 
   $scope.findByCode = (code) ->
     if $scope.customers

app/models/customer.rb

@@ -5,8 +5,9 @@ class Customer < ActiveRecord::Base
   belongs_to :user, class_name: Spree.user_class
 
   before_validation :downcase_email
+  before_validation :empty_code
 
-  validates :code, uniqueness: { scope: :enterprise_id, allow_blank: true, allow_nil: true }
+  validates :code, uniqueness: { scope: :enterprise_id, allow_nil: true }
   validates :email, presence: true, uniqueness: { scope: :enterprise_id, message: I18n.t('validation_msg_is_associated_with_an_exising_customer') }
   validates :enterprise_id, presence: true
 
@@ -20,6 +21,10 @@ class Customer < ActiveRecord::Base
     email.andand.downcase!
   end
 
+  def empty_code
+    self.code = nil if code.blank?
+  end
+
   def associate_user
     self.user = user || Spree::User.find_by_email(email)
   end

spec/models/customer_spec.rb

@@ -1,6 +1,23 @@
 require 'spec_helper'
 
 describe Customer, type: :model do
+  describe 'an existing customer' do
+    let(:customer) { create(:customer) }
+
+    it "saves its code" do
+      code = "code one"
+      customer.code = code
+      customer.save
+      expect(customer.code).to eq code
+    end
+
+    it "can remove its code" do
+      customer.code = ""
+      customer.save
+      expect(customer.code).to be nil
+    end
+  end
+
   describe 'creation callbacks' do
     let!(:user1) { create(:user) }
     let!(:user2) { create(:user) }