distinct.rb

class Array
  def first
    self[0]
  end

  def last
    self[self.size - 1]
  end

  def distinct
    source = self
    target = []
    dups = Set.new
    source.each do |source_elem|
      target.push(source_elem) unless dups.add?(source_elem).nil?
    end 
    target
  end
end

class DistinctifierTest
  attr_reader :sample, :actual, :method

  def initialize(sample, method = :distinct)
    @sample = sample
    @method = method
  end 
  
  def act
    @actual = sample.send(method)
  end 
  
  def assert
    actual == sample.uniq
  end 

  def run 
    act 
    if assert
      puts 'Assert success!'
    else
      puts "Assert failed. Sample: #{sample}. Actual: #{actual}"
    end 
    self
  end 
end

require 'benchmark'
class DistinctifierTestRunner
  attr_reader :method

  def initialize(method = :distinct)
    @method = method
  end

  def run(*samples)
    samples.each do |sample|
      DistinctifierTest.new(sample, method).run
    end 
  end 

  def run_with_benchmark(*samples)
    Benchmark.bm(7) do |benchmark|
      samples.each do |sample|
        benchmark.report do
          DistinctifierTest.new(sample, method).run
        end 
      end 
    end
  end

  def self.run(*samples)
    new.run(*samples)
  end 
end

#DistinctifierTestRunner.run(%w[a b c], %w[b a c c e d d])

require 'faker'
class EmailSampleGenerator
  attr_reader :count, :rand_range, :email_factory, :emails, :half_count

  def initialize(count: 4, rand_range: 1..2, email_factory: Faker::Internet)
    @count = count
    @rand_range = rand_range
    @email_factory = email_factory
    @emails = []
    @half_count = (count.to_f / 2).to_i
  end

  def gen
    @emails = []
    half_count.times do
      emails.push email_factory.email
    end
    half_count.times do
      emails.insert(rand_array_location, emails[rand_array_location])
    end
    emails
  end

  private

  def duplicate_count
    rand(rand_range)
  end

  def rand_array_location
    loc = rand(0...emails.size)
    return 0 if loc.nil?
    loc
  end
end

email_source = EmailSampleGenerator.new.gen

puts "\nsource:"
print email_source
puts "\nactual:"
print email_source.distinct
puts "\n"

#DistinctifierTestRunner.run(email_source)
DistinctifierTestRunner.new(:uniq).run_with_benchmark(EmailSampleGenerator.new(count: 10000).gen)
#DistinctifierTestRunner.new(:distinct3).run_with_benchmark(EmailSampleGenerator.new(count: 10000).gen)
DistinctifierTestRunner.new(:distinct4).run_with_benchmark(EmailSampleGenerator.new(count: 10000).gen)