render_to_output_buffer

test/integration/blank_test.rb

@@ -1,12 +1,10 @@
 require 'test_helper'
 
 class FoobarTag < Liquid::Tag
-  def render(context, output = '')
+  def render_to_output_buffer(context, output)
     output << ' '
     output
   end
-
-  Liquid::Template.register_tag('foobar', FoobarTag)
 end
 
 class BlankTestFileSystem
@@ -32,7 +30,9 @@ class BlankTest < Minitest::Test
   end
 
   def test_new_tags_are_not_blank_by_default
-    assert_template_result(" " * N, wrap_in_for("{% foobar %}"))
+    with_custom_tag('foobar', FoobarTag) do
+      assert_template_result(" " * N, wrap_in_for("{% foobar %}"))
+    end
   end
 
   def test_loops_are_blank