I18n: use I18n for select helpers' prompt text

[#2252 state:committed]
Signed-off-by: NJeremy Kemper <jeremy@bitsweat.net>

actionpack/lib/action_view/helpers/form_options_helper.rb

@@ -571,7 +571,8 @@ def add_options(option_tags, options, value = nil)
             option_tags = "<option value=\"\">#{options[:include_blank] if options[:include_blank].kind_of?(String)}</option>\n" + option_tags
           end
           if value.blank? && options[:prompt]
-            ("<option value=\"\">#{options[:prompt].kind_of?(String) ? options[:prompt] : 'Please select'}</option>\n") + option_tags
+            prompt = options[:prompt].kind_of?(String) ? options[:prompt] : I18n.translate('support.select.prompt', :default => 'Please select')
+            "<option value=\"\">#{prompt}</option>\n" + option_tags
           else
             option_tags
           end

actionpack/lib/action_view/locale/en.yml

@@ -108,3 +108,7 @@
         # The variable :count is also available
         body: "There were problems with the following fields:"
 
+  support:
+    select:
+      # default value for :prompt => true in FormOptionsHelper
+      prompt: "Please select"
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actionpack/test/template/form_options_helper_i18n_test.rb

+require 'abstract_unit'
+
+class FormOptionsHelperI18nTests < ActionView::TestCase
+  tests ActionView::Helpers::FormOptionsHelper
+
+  def setup
+    @prompt_message = 'Select!'
+    I18n.backend.send(:init_translations)
+    I18n.backend.store_translations :en, :support => { :select => { :prompt => @prompt_message } }
+  end
+
+  def teardown
+    I18n.backend = I18n::Backend::Simple.new
+  end
+
+  def test_select_with_prompt_true_translates_prompt_message
+    I18n.expects(:translate).with('support.select.prompt', { :default => 'Please select' })
+    select('post', 'category', [], :prompt => true)
+  end
+
+  def test_select_with_translated_prompt
+    assert_dom_equal(
+      %Q(<select id="post_category" name="post[category]"><option value="">#{@prompt_message}</option>\n</select>),
+      select('post', 'category', [], :prompt => true)
+    )
+  end
+end
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