Implement I18n::Alchemy#unlocalize to return the original target

Closes carlosantoniodasilva#39

CHANGELOG.md

@@ -1,3 +1,7 @@
+## master
+
+* Add unlocalize to get the original target ([@sobrinho](https://github.com/sobrinho))
+
 ## v0.3.0 - 2018-09-08
 
 * Update I18n dependency to require >= 0.7, allowing to install more recent versions ([@nazarhussain](https://github.com/nazarhussain))

README.md

@@ -89,6 +89,18 @@ I18n.with_locale :pt do
 end
 ```
 
+Keep in mind that `product.localized` is a proxy object and if you need the original value, you need either to use the original object or unlocalize the proxy for action view helpers like `date_select`:
+
+```ruby
+# In case you have the original target.
+f.date_select :released_at, selected: @product.released_at
+
+# In case you don't have the original target, you can use `unlocalize` to get it back.
+f.date_select :released_at, selected: @localized.unlocalize.released_at
+```
+
+This is necessary because such Rails helpers expects a Date/Time object and not a localized string.
+
 ### Localizing methods
 
 Given a product model with a `total` method, that is a simple calculation of `quantity * price`, you can tell **I18n::Alchemy** to localize that method for you together with the attributes:

lib/i18n_alchemy/proxy.rb

@@ -25,6 +25,12 @@ def initialize(target, attributes = nil)
         assign_attributes(attributes) if attributes
       end
 
+      # Returns the original target. This is useful for action view helpers that
+      # expects the unlocalized value like a +Date+ or +Time+.
+      def unlocalize
+        @target
+      end
+
       # Override to_param to always return the +proxy.to_param+. This allow us
       # to integrate with action view.
       def to_param

test/i18n_alchemy/proxy_test.rb

@@ -1,6 +1,10 @@
 require "test_helper"
 
 class ProxyTest < I18n::Alchemy::ProxyTestCase
+  def test_unlocalize
+    assert_equal @product, @localized.unlocalize
+  end
+
   def test_delegates_orm_methods_to_target_object
     assert @product.new_record?
     assert @localized.save!(:name => "foo", :price => 1.99)