haml_tag should only close elements that are listed as autoclose.

E.g. we want

  haml_tag :br #=> "<br />\n"

but

  haml_tag :p #=> "<p>\n</p>\n"

lib/haml/engine.rb

@@ -265,6 +265,7 @@ END
     # This should remain loadable from #inspect.
     def options_for_buffer
       {
+        :autoclose => @options[:autoclose],
         :preserve => @options[:preserve],
         :attr_wrapper => @options[:attr_wrapper],
         :ugly => @options[:ugly],

lib/haml/helpers.rb

@@ -286,6 +286,8 @@ module Haml
     #   </table>
     #
     def haml_tag(name, attributes = {}, alt_atts = {}, &block)
+      name = name.to_s
+
       text = nil
       if attributes.is_a? String
         text = attributes
@@ -294,7 +296,8 @@ module Haml
 
       attributes = Haml::Precompiler.build_attributes(
         haml_buffer.html?, haml_buffer.options[:attr_wrapper], attributes)
-      if text.nil? && block.nil?
+
+      if text.nil? && block.nil? && haml_buffer.options[:autoclose].include?(name)
         puts "<#{name}#{attributes} />"
         return nil
       end

test/haml/helper_test.rb

@@ -100,6 +100,14 @@ class HelperTest < Test::Unit::TestCase
     assert_equal("<p id='foo&amp;bar'>baz</p>\n", render("%p{:id => 'foo&bar'} baz", :escape_html => true))
   end
 
+  def test_haml_tag_autoclosed_tags_are_closed
+    assert_equal("<br class='foo' />\n", render("- haml_tag :br, :class => 'foo'"))
+  end
+
+  def test_haml_tag_non_autoclosed_tags_arent_closed
+    assert_equal("<p>\n</p>\n", render("- haml_tag :p"))
+  end
+
   def test_is_haml
     assert(!ActionView::Base.new.is_haml?)
     assert_equal("true\n", render("= is_haml?"))