Added an `enforce_utf8` hash option for `form_tag` method

Control to output a hidden input tag with name `utf8` without monkey
patching

Before:

    form_tag
    # => '<form>..<input name="utf8" type="hidden" value="&#x2713;" />..</form>'

After:

    form_tag
    # => '<form>..<input name="utf8" type="hidden" value="&#x2713;" />..</form>'

    form_tag({}, { :enforce_utf8 => false })
    # => '<form>....</form>'

1 files changed, 16 insertions, 1 deletions

diff --git a/actionview/test/template/form_tag_helper_test.rb b/actionview/test/template/form_tag_helper_test.rb
index 70fc6a588b..22bf438a56 100644
--- a/actionview/test/template/form_tag_helper_test.rb
+++ b/actionview/test/template/form_tag_helper_test.rb
@@ -12,9 +12,10 @@ class FormTagHelperTest < ActionView::TestCase
 
   def hidden_fields(options = {})
     method = options[:method]
+    enforce_utf8 = options.fetch(:enforce_utf8, true)
 
     txt =  %{<div style="margin:0;padding:0;display:inline">}
-    txt << %{<input name="utf8" type="hidden" value="&#x2713;" />}
+    txt << %{<input name="utf8" type="hidden" value="&#x2713;" />} if enforce_utf8
     if method && !%w(get post).include?(method.to_s)
       txt << %{<input name="_method" type="hidden" value="#{method}" />}
     end
@@ -110,6 +111,20 @@ class FormTagHelperTest < ActionView::TestCase
     assert_dom_equal expected, actual
   end
 
+  def test_form_tag_enforce_utf8_true
+    actual = form_tag({}, { :enforce_utf8 => true })
+    expected = whole_form("http://www.example.com", :enforce_utf8 => true)
+    assert_dom_equal expected, actual
+    assert actual.html_safe?
+  end
+
+  def test_form_tag_enforce_utf8_false
+    actual = form_tag({}, { :enforce_utf8 => false })
+    expected = whole_form("http://www.example.com", :enforce_utf8 => false)
+    assert_dom_equal expected, actual
+    assert actual.html_safe?
+  end
+
   def test_form_tag_with_block_in_erb
     output_buffer = render_erb("<%= form_tag('http://www.example.com') do %>Hello world!<% end %>")