don't delete the return to url from session if the requested format is not navigational

closes #2122

lib/devise/controllers/helpers.rb

@@ -162,8 +162,8 @@ module Devise
         users.any?
       end
 
-      # Returns and delete the url stored in the session for the given scope. Useful
-      # for giving redirect backs after sign up:
+      # Returns and delete (if it's navigational format) the url stored in the session for
+      # the given scope. Useful for giving redirect backs after sign up:
       #
       # Example:
       #
@@ -171,7 +171,12 @@ module Devise
       #
       def stored_location_for(resource_or_scope)
         scope = Devise::Mapping.find_scope!(resource_or_scope)
+
+        if is_navigational_format?
           session.delete("#{scope}_return_to")
+        else
+          session["#{scope}_return_to"]
+        end
       end
 
       # The scope root url to be used when he's signed in. By default, it first

test/controllers/sessions_controller_test.rb

@@ -13,6 +13,34 @@ class SessionsControllerTest < ActionController::TestCase
     end
   end
 
+  test "#create delete the url stored in the session if the requested format is navigational" do
+    request.env["devise.mapping"] = Devise.mappings[:user]
+    request.session["user_return_to"] = 'foo.bar'
+
+    user = create_user
+    user.confirm!
+    post :create, :user => {
+      :email => user.email,
+      :password => user.password
+    }
+
+    assert_nil request.session["user_return_to"]
+  end
+
+  test "#create doesn't delete the url stored in the session if the requested format is not navigational" do
+    request.env["devise.mapping"] = Devise.mappings[:user]
+    request.session["user_return_to"] = 'foo.bar'
+
+    user = create_user
+    user.confirm!
+    post :create, :format => 'json', :user => {
+      :email => user.email,
+      :password => user.password
+    }
+
+    assert_equal 'foo.bar', request.session["user_return_to"]
+  end
+
   test "#create doesn't raise exception after Warden authentication fails when TestHelpers included" do
     request.env["devise.mapping"] = Devise.mappings[:user]
     post :create, :user => {