time helper

method_missing timezone helper.rb

# spec_helper.rb

RSpec.configure do |config| 
  # ...
  config.include(MyWebsite::Helpers)
end


# spec/support/my_website/helpers.rb

module MyWebsite
  module Helpers
    def method_missing(meth, *args, &block)
      matched = meth.to_s.match(/^in_(.*)_at_(.*)(am|pm)(_on_(\D*)(\d{1,2}))?$/)
      old_zone = Time.zone.name

      if matched
        location = matched[1]
        hour     = matched[2].split('').insert(-3, ':').join
        am_pm    = matched[3]
        date     = matched[4]
        month    = matched[5]
        day      = matched[6]

        if date.present?
          date = "#{month} #{day} at "
        else
          date = ''
        end

        location_map = {
          'sydney' => 'Sydney',
          'london' => 'UTC',
          'boston' => 'America/New_York',
          'ny' => 'America/New_York',
          'chicago' => 'America/Chicago',
          'denver' => 'America/Denver',
          'la' => 'America/Los_Angeles',
        }

        old_zone = Time.zone.name
        Time.zone = location_map[location]
        Chronic.time_class = Time.zone
        this_time = Chronic.parse("#{date}#{hour}#{am_pm}").utc

        if block_given?
          Timecop.freeze(this_time) do
            block.call
          end
        else
          this_time
        end
      else
        super
      end
    ensure
      Time.zone = old_zone
    end
  end
end