Fixed serialization issues with multiple includes with options

activemodel/lib/active_model/serialization.rb

@@ -126,7 +126,7 @@ def serializable_add_includes(options = {}) #:nodoc:
         return unless include = options[:include]
 
         unless include.is_a?(Hash)
-          include = Hash[Array.wrap(include).map { |n| [n, {}] }]
+          include = Hash[Array.wrap(include).map { |n| n.is_a?(Hash) ? n.to_a.first : [n, {}] }]
         end
 
         include.each do |association, opts|

activemodel/test/cases/serialization_test.rb

@@ -140,4 +140,12 @@ def test_except_include
     assert_equal expected , @user.serializable_hash(:except => :gender, :include => {:friends => {:except => :gender}})
   end
 
+  def test_multiple_includes_with_options
+    expected =  {"email"=>"david@example.com", "gender"=>"male", "name"=>"David",
+                 :address=>{"street"=>"123 Lane"},
+                 :friends=>[{"name"=>'Joe', "email"=>'joe@example.com', "gender"=>'male'},
+                            {"name"=>'Sue', "email"=>'sue@example.com', "gender"=>'female'}]}
+    assert_equal expected , @user.serializable_hash(:include => [{:address => {:only => "street"}}, :friends])
+  end
+
 end