Ruby:离特定日期最近的日期

require 'date'

def nearest_date(target_date, dates)
  target_date = Date.parse(target_date)
  nearest_date = nil
  min_diff = Float::INFINITY

  dates.each do |date|
    diff = (Date.parse(date) - target_date).abs
    if diff < min_diff
      min_diff = diff
      nearest_date = date
    end
  end

  nearest_date
end

target_date = '2022-01-01'
dates = ['2021-12-31', '2022-01-02', '2022-01-05']

nearest_date = nearest_date(target_date, dates)
puts "离 #{target_date} 最近的日期是 #{nearest_date}"