Fix nested hash params in Consumer#request posts

Author: ernie

lib/oauth/consumer.rb

@@ -352,9 +352,8 @@ def create_http_request(http_method, path, *arguments)
       end
 
       if data.is_a?(Hash)
-        form_data = {}
-        data.each {|k,v| form_data[k.to_s] = v if !v.nil?}
-        request.set_form_data(form_data)
+        request.body = OAuth::Helper.normalize(data)
+        request.content_type = 'application/x-www-form-urlencoded'
       elsif data
         if data.respond_to?(:read)
           request.body_stream = data

test/test_consumer.rb

@@ -89,6 +89,27 @@ def test_site_with_path
     @consumer.request(:get, '/people', nil, {})
   end
 
+  def test_post_of_nested_params_maintains_nesting
+    @consumer=OAuth::Consumer.new(
+      "key",
+      "secret",
+      {
+          :site=>"http://twitter.com"
+      })
+    request = @consumer.create_signed_request(
+      :post,
+      '/people',
+      nil,
+      {},
+      {
+        :key => {
+          :subkey => 'value'
+        }
+      })
+    assert_equal 'key%5Bsubkey%5D=value', request.body
+    assert_equal request.content_type, 'application/x-www-form-urlencoded'
+  end
+
   def test_override_paths
     @consumer=OAuth::Consumer.new(
       "key",