Benchmark of changing optimized route generation to pre-splitting the route versus using gsub with a complex route

optimized_routes.rb

require 'benchmark/ips'
require 'action_controller/railtie'

ROUTE     = '/posts/:post_id/comments/:id.:format'
PARTS     = [:post_id, :id, :format]
OPTIMIZED = ["/", "posts", "/", :post_id, "/", "comments", "/", :id, ".", :format]
KLASS     = ActionDispatch::Journey::Router::Utils

def optimized_helper_1(*args)
  path = ROUTE.dup
  klass = ActionDispatch::Journey::Router::Utils

  PARTS.zip(args) do |part, arg|
    parameterized_arg = arg.to_param

    if parameterized_arg.nil? || parameterized_arg.empty?
      raise ActionController::UrlGenerationError
    end

    path.gsub!(/(\*|:)#{part}/, klass.escape_fragment(parameterized_arg))
  end
  path
end

def optimized_helper_2(*args)
  params  = Hash[parameterize_args(args)]
  missing = missing_keys(params)

  unless missing.empty?
    raise ActionController::UrlGenerationError
  end

  OPTIMIZED.map{ |segment| replace_segment(params, segment) }.join
end

def replace_segment(params, segment)
  Symbol === segment ? KLASS.escape_fragment(params[segment]) : segment
end

def parameterize_args(args)
  [].tap do |parameterized_args|
    PARTS.zip(args) do |part, arg|
      parameterized_arg = arg.to_param
      parameterized_args << [part, parameterized_arg]
    end
  end
end

def missing_keys(args)
  args.select{ |part, arg| arg.nil? || arg.empty? }.keys
end

Benchmark.ips do |x|
  x.report('Current Helper: ') { optimized_helper_1(2, 1, :json) }
  x.report('New Helper:     ') { optimized_helper_2(2, 1, :json) }
end

results.txt

Calculating -------------------------------------
    Current Helper:       2367 i/100ms
    New Helper:           5382 i/100ms
-------------------------------------------------
    Current Helper:     29506.0 (±3.2%) i/s -     149121 in   5.059294s
    New Helper:         78815.5 (±4.1%) i/s -     398268 in   5.062161s