Fix some edge cases for AV `select` helper with `:selected` option

actionview/CHANGELOG.md

+*   Fix some edge cases for AV `select` helper with `:selected` option
+
+    *Bogdan Gusiev*
+
 *   Ability to pass block to `select` helper
 
         <%= select(report, "campaign_ids") do %>

actionview/lib/action_view/helpers/tags/base.rb

@@ -119,7 +119,8 @@ def select_content_tag(option_tags, options, html_options)
           html_options = html_options.stringify_keys
           add_default_name_and_id(html_options)
           options[:include_blank] ||= true unless options[:prompt] || select_not_required?(html_options)
-          select = content_tag("select", add_options(option_tags, options, value(object)), html_options)
+          value = options.fetch(:selected) { value(object) }
+          select = content_tag("select", add_options(option_tags, options, value), html_options)
 
           if html_options["multiple"] && options.fetch(:include_hidden, true)
             tag("input", :disabled => html_options["disabled"], :name => html_options["name"], :type => "hidden", :value => "") + select

actionview/test/template/form_options_helper_test.rb

@@ -798,6 +798,22 @@ def test_select_with_disabled_value
     )
   end
 
+  def test_select_not_existing_method_with_selected_value
+    @post = Post.new
+    assert_dom_equal(
+      "<select id=\"post_locale\" name=\"post[locale]\"><option value=\"en\">en</option>\n<option value=\"ru\" selected=\"selected\">ru</option></select>",
+      select("post", "locale", %w( en ru ), :selected => 'ru')
+    )
+  end
+
+  def test_select_with_prompt_and_selected_value
+    @post = Post.new
+    assert_dom_equal(
+      "<select id=\"post_category\" name=\"post[category]\"><option value=\"one\">one</option>\n<option selected=\"selected\" value=\"two\">two</option></select>",
+      select("post", "category", %w( one two ), :selected => 'two', :prompt => true)
+    )
+  end
+  
   def test_select_with_disabled_array
     @post = Post.new
     @post.category = "<mus>"