Do not allow transfers to same account

It adds a validation on the Transfer model and shows a flash error
message when that happens, without making the actual movement.

Author: sauloperez

app/controllers/transfers_controller.rb

@@ -1,8 +1,16 @@
 class TransfersController < ApplicationController
   def create
     @source = find_source
-    Transfer.create(transfer_params.merge source: @source)
     @account = Account.find(transfer_params[:destination])
+    transfer = Transfer.new(
+      transfer_params.merge(source: @source, destination: @account)
+    )
+
+    if transfer.valid?
+      transfer.make_movements
+    else
+      flash[:error] = transfer.errors.full_messages.to_sentence
+    end
     redirect_to redirect_target
   end
 

app/models/transfer.rb

@@ -17,6 +17,8 @@ class Transfer < ActiveRecord::Base
   belongs_to :operator, class_name: "User"
   has_many :movements
 
+  validate :different_source_and_destination
+
   after_create :make_movements
 
   def make_movements
@@ -39,4 +41,9 @@ def source_id
   def destination_id
     destination.respond_to?(:id) ? destination.id : destination
   end
+
+  def different_source_and_destination
+    return unless source == destination
+    errors.add(:base, :same_account)
+  end
 end

config/locales/ca.yml

@@ -102,6 +102,10 @@ ca:
           attributes:
             web:
               url_format_invalid: Format de URL no vàlid
+        transfer:
+          attributes:
+            base:
+              same_account: No es pot fer una transacció al mateix compte
 
   # ETIQUETAS VARIADAS EN PLANTILLAS
 

config/locales/en.yml

@@ -102,6 +102,10 @@ en:
           attributes:
             web:
               url_format_invalid: invalid URL format
+        transfer:
+          attributes:
+            base:
+              same_account: A transfer cannot be made to the same account
 
   # ETIQUETAS VARIADAS EN PLANTILLAS
 

config/locales/es.yml

@@ -102,6 +102,10 @@ es:
           attributes:
             web:
               url_format_invalid: Formato de URL no válido
+        transfer:
+          attributes:
+            base:
+              same_account: No se puede hacer una transacción a la misma cuenta
 
   # ETIQUETAS VARIADAS EN PLANTILLAS