Remove "use of nil in void context" warnings.

test/engine_test.rb

@@ -740,6 +740,7 @@ HTML
   %p= s
 - end; nil)
 HAML
+    end
   end
 
   def test_if_without_content_and_else

test/helper_test.rb

@@ -166,7 +166,7 @@ HAML
 HTML
 - (foo = capture_haml(13) do |a|
   %p= a
-- end; nil)
+- end)
 = foo.inspect
 HAML
   end

test/template_test.rb

@@ -197,7 +197,7 @@ HTML
     bar
     = "foo".gsub(/./) do |s|
       - "flup"
-  - end; nil)
+  - end)
   baz
 HAML
   end