Inline templates leak memory

[tenderlove]

I don't have a fix for this yet, but inline templates definitely leak memory.

Here is a test:

require "action_pack"
require "action_controller"
require "rack/utils"

class TestController < ActionController::Base
  def self.controller_path; "test"; end

  def index
    render inline: 'Methods: <%= methods.length %>'
  end
end

def send_request
  env = Rack::MockRequest.env_for("/",
                                  "REMOTE_ADDR"     => "0.0.0.0",
                                  "HTTP_USER_AGENT" => "Rails Testing",
                                 )

  request = ActionDispatch::Request.new(env)
  res = TestController.make_response!(request)
  controller = TestController.new
  str = ''
  controller.dispatch(:index, request, res).last.each { |x| str << x }
  str
end

puts send_request
10.times { |i|
  500.times { send_request }
  p i => send_request
}

If you run this script you'll see the number of methods on AV::Base increase. We use the object id to calculate a method name, so the leak isn't exactly linear as some object ids will get recycled:

$ be ruby a_controller_test.rb
Methods: 349
{0=>"Methods: 847"}
{1=>"Methods: 1337"}
{2=>"Methods: 1818"}
{3=>"Methods: 2290"}
{4=>"Methods: 2768"}
{5=>"Methods: 3232"}
{6=>"Methods: 3719"}
{7=>"Methods: 4197"}
{8=>"Methods: 4680"}
{9=>"Methods: 5154"}

[tenderlove]

This only impacts master, and I broke it by removing the finalizers. So I'll fix it.