quick and dirty monkey patch to see which `require`d files are taking a long time to load

benchmarking_require.rb

# quick and dirty monkey patch to see which `require`d files are taking a long time to load
# Usage: 'require "benchmarking_require"' in spec_helper.rb

require "benchmark"
module Kernel
  def require_with_benchmark path
    x = nil
    m = Benchmark.measure do
      x = require_without_benchmark path
    end
    @@times << [path, m.total] if m.total > 0.1
    x
  end
  at_exit do
    @@times.sort_by! { |x| -x[1] }
    @@times.each do |time|
      puts "#{"%1.4f" % time[1]}\t#{time[0].gsub(/.*\/gems\//, "")}"
    end
  end

  alias_method :require_without_benchmark, :require
  alias_method :require, :require_with_benchmark
  @@times = []
end