create a PaymentEngine::Interface to handle with missing methods on payment engines [# 67561316]

app/models/concerns/contribution/payment_engine_handler.rb

@@ -3,27 +3,18 @@ module Contribution::PaymentEngineHandler
 
   included do
 
+    delegate :can_do_refund?, to: :payment_engine
+
     def payment_engine
-      PaymentEngines.find_engine(self.payment_method) rescue nil
+      PaymentEngines.find_engine(self.payment_method) || PaymentEngines::Interface.new
     end
 
-    def can_do_refund?
-      engine_handler { |engine| engine[:can_do_refund?] }
+    def review_path
+      payment_engine.review_path(self)
     end
 
-    %i(review_path direct_refund).each do |method_name|
-      define_method method_name do
-        engine_handler { |engine| engine[method_name].try(:call, self) }
-      end
+    def direct_refund
+      payment_engine.direct_refund(self)
     end
-
-    private
-
-    def engine_handler
-      if payment_engine
-        yield payment_engine
-      end
-    end
-
   end
 end

lib/payment_engines.rb

@@ -3,7 +3,7 @@ class PaymentEngines
 
   def self.find_engine name
     @@engines.find do |engine|
-      engine[:name].downcase == name.downcase
+      engine.name.downcase == name.downcase
     end
   end
 
@@ -16,7 +16,7 @@ class PaymentEngines
   end
 
   def self.engines
-    @@engines.sort{|a,b| (a[:locale] == I18n.locale.to_s ? -1 : 1) }
+    @@engines.sort{|a,b| (a.locale == I18n.locale.to_s ? -1 : 1) }
   end
 
   def self.create_payment_notification attributes

lib/payment_engines/interface.rb

@@ -0,0 +1,15 @@
+class PaymentEngines
+  class Interface
+
+    def name; end
+
+    def locale; end
+
+    def review_path(contribution); end
+
+    def can_do_refund?; end
+
+    def direct_refund(contribution); end
+
+  end
+end

spec/lib/payment_engines_spec.rb

@@ -3,10 +3,23 @@
 require 'spec_helper'
 
 describe PaymentEngines do
-  let(:engine){ {name: 'test', review_path: ->(contribution){ "/#{contribution}" }, locale: 'en'} }
-  let(:engine_pt){ {name: 'test pt', review_path: ->(contribution){ "/#{contribution}" }, locale: 'pt'} }
   let(:contribution){ FactoryGirl.create(:contribution) }
-  before{ PaymentEngines.clear }
+  let(:paypal_engine) { double }
+  let(:moip_engine) { double }
+
+  before do
+    PaymentEngines.clear
+    paypal_engine.stub(:name).and_return('PayPal')
+    paypal_engine.stub(:review_path).with(contribution).and_return("/#{contribution}")
+    paypal_engine.stub(:locale).and_return('en')
+
+    moip_engine.stub(:name).and_return('MoIP')
+    moip_engine.stub(:review_path).with(contribution).and_return("/#{contribution}")
+    moip_engine.stub(:locale).and_return('pt')
+  end
+
+  let(:engine){ paypal_engine }
+  let(:engine_pt){ moip_engine }
 
   describe ".find_engine" do
     before do
@@ -14,9 +27,9 @@ describe PaymentEngines do
       PaymentEngines.register engine_pt
     end
 
-    subject { PaymentEngines.find_engine('test pt') }
+    subject { PaymentEngines.find_engine('MoIP') }
 
-    it { should == engine_pt}
+    it { should == engine_pt }
   end
 
   describe ".register" do

spec/models/concerns/contribution/payment_engine_handler_spec.rb

@@ -1,15 +1,23 @@
 require 'spec_helper'
 
 describe Contribution::PaymentEngineHandler do
-  let(:engine){ { name: 'moip', review_path: ->(contribution){ "/#{contribution}" }, locale: 'en' } }
   let(:contribution){ create(:contribution, payment_method: 'MoIP') }
+  let(:moip_engine) { double }
 
   before do
     Contribution.any_instance.unstub(:direct_refund)
     PaymentEngines.clear
-    engine
+
+    moip_engine.stub(:name).and_return('MoIP')
+    moip_engine.stub(:review_path).and_return("/#{contribution}")
+    moip_engine.stub(:locale).and_return('pt')
+    moip_engine.stub(:can_do_refund?).and_return(false)
+    moip_engine.stub(:direct_refund).and_return(false)
+
   end
 
+  let(:engine){ moip_engine }
+
   describe "#payment_engine" do
     subject { contribution.payment_engine }
 
@@ -20,7 +28,7 @@ describe Contribution::PaymentEngineHandler do
     end
 
     context "when contribution don't have a payment engine" do
-      it { should eq(nil) }
+      it { should be_a_kind_of(PaymentEngines::Interface) }
     end
   end
 
@@ -29,8 +37,8 @@ describe Contribution::PaymentEngineHandler do
 
     context "when contribution has a payment engine with direct refund enabled" do
       before do
-        PaymentEngines.register(engine.merge!({ can_do_refund?: true }))
-        contribution.stub(:direct_refund).and_return(true)
+        moip_engine.stub(:can_do_refund?).and_return(true)
+        PaymentEngines.register(engine)
       end
 
       it { should be_true }
@@ -50,7 +58,9 @@ describe Contribution::PaymentEngineHandler do
 
     context "when contribution has a payment engine with direct refund enabled" do
       before do
-        PaymentEngines.register(engine.merge!({ direct_refund: ->(contribution) { true } }))
+        moip_engine.stub(:can_do_refund?).and_return(true)
+        moip_engine.stub(:direct_refund).and_return(true)
+        PaymentEngines.register(engine)
       end
 
       it { should be_true }
@@ -69,9 +79,12 @@ describe Contribution::PaymentEngineHandler do
     subject { contribution.review_path }
 
     context "when contribution has a payment engine" do
-      before { PaymentEngines.register engine }
+      before do
+        contribution.stub(:payment_engine).and_return(engine)
+        PaymentEngines.register engine
+      end
 
-      it { should eq(engine[:review_path].call(contribution)) }
+      it { should eq(engine.review_path(contribution)) }
     end
 
     context "when contribution don't have a payment engine" do