You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: best_customers_test.rb
    path of file: ./repos/workarea/core/test/models/workarea/insights
    
    the code of the file until where you have to start completion: require 'test_helper'

module Workarea
  module Insights
    class BestCustomersTest < TestCase
      def test_results
        Metrics::User.save_order(email: 'bcrouse@workarea.com', revenue: 0.5.to_m, at: 120.days.ago)
        Metrics::User.save_order(email: 'bcrouse0@workarea.com', revenue: 1.to_m, at: 60.days.ago)
        Metrics::User.save_order(email: 'bcrouse1@workarea.com', revenue: 1.to_m, at: 1.day.ago)
        Metrics::User.save_order(email: 'bcrouse2@workarea.com', revenue: 10.to_m, at: 2.days.ago)
        Metrics::User.save_order(email: 'bcrouse2@workarea.com', revenue: 10.to_m, at: 3.days.ago)
        Metrics::User.save_order(email: 'bcrouse3@workarea.com', revenue: 20.to_m, at: 2.days.ago)
        Metrics::User.save_order(email: 'bcrouse3@workarea.com', revenue: 20.to_m, at: 3.days.ago)
        Metrics::User.save_order(email: 'bcrouse3@workarea.com', revenue: 20.to_m, at: 4.days.ago)
        Metrics::User.save_order(email: 'bcrouse4@workarea.com', revenue: 30.to_m, at: 1.days.ago)
        Metrics::User.save_order(email: 'bcrouse4@workarea.com', revenue: 30.to_m, at:
    
      def test_falling_back_to_longer_timespans
        Metrics::User.save_order(email: 'bcrouse@workarea.com', revenue: 0.5.to_m, at: 600.days.ago)
        Metrics::User.save_order(email: 'bcrouse0@workarea.com', revenue: 1.to_m, at: 300.days.ago)
        Metrics::User.save_order(email: 'bcrouse1@workarea.com', revenue: 1.to_m, at: 31.day.ago)
        Metrics::User.save_order(email: 'bcrouse2@workarea.com', revenue: 10.to_m, at: 32.days.ago)
        Metrics::User.save_order(email: 'bcrouse2@workarea.com', revenue: 10.to_m, at: 33.days.ago)
        Metrics::User.save_order(email: 'bcrouse3@workarea.com', revenue: 20.to_m, at: 32.days.ago)
        Metrics::User.save_order(email: 'bcrouse3@workarea.com', revenue: 20.to_m, at: 33.days.ago)
        Metrics::User.save_order(email: 'bcrouse3@workarea.com', revenue: 20.to_m, at: 34.days.ago)
        Metrics::User.save_order(email: 'bcrouse4@workarea.com', revenue: 30.to_m, at: 31.days.ago)
        Metrics::User.save_order(email: 'bcrouse4@workarea.com', revenue: 30.to_m, at: 32.days.ago)

        Metrics::UpdateUserAggregations.update!
        BestCustomers.generate_monthly!
        assert_equal(1, BestCustomers.count)

        best_customers = BestCustomers.first
        assert_equal(2, best_customers.results.length)
        assert_equal('bcrouse3@workarea.com', best_customers.results.first['_id'])
        assert_equal('bcrouse4@workarea.com', best_customers.results.second['_id'])
      end