change active_support String#to_date

gistfile1.rb

require 'benchmark'

class String
  def old_to_date
    unless blank?
      date_values = ::Date._parse(self, false).values_at(:year, :mon, :mday)

      ::Date.new(*date_values)
    end
  end

  def new_to_date
    ::Date.parse(self, false) unless blank?
  end

  def blank?
    false
  end
end

date = '1/2/3'

Benchmark.bm do |x|
  x.report('old') { 100000.times { date.old_to_date }}
  x.report('new') { 100000.times { date.new_to_date }}
end
=> results
       user     system      total        real
old  0.950000   0.000000   0.950000 (  0.952705)
new  0.940000   0.000000   0.940000 (  0.945149)