[Haml] Fix interpolated if statements with HTML-escaping.

doc-src/HAML_CHANGELOG.md

@@ -7,6 +7,8 @@
 
 * Fix the `:encoding` option under Ruby 1.9.2.
 
+* Fix interpolated if statement when HTML escaping is enabled.
+
 * Allow the `--unix-newlines` flag to work on Unix, where it's a no-op.
 
 ## 3.0.18

lib/haml/precompiler.rb

@@ -1024,7 +1024,7 @@ END
           res << '#{'
         else
           content = eval('"' + balance(scan, ?{, ?}, 1)[0][0...-1] + '"')
-          content = "Haml::Helpers.html_escape(#{content})" if opts[:escape_html]
+          content = "Haml::Helpers.html_escape((#{content}))" if opts[:escape_html]
           res << '#{' + content + "}"# Use eval to get rid of string escapes
         end
       end

test/haml/engine_test.rb

@@ -774,6 +774,14 @@ HTML
 HAML
   end
 
+  def test_escape_html_with_interpolated_if_statement
+    assert_equal(<<HTML, render(<<HAML, :escape_html => true))
+foo,
+HTML
+foo\#{"," if true}
+HAML
+  end
+
   # HTML escaping tests
 
   def test_ampersand_equals_should_escape