The script of unit tests.

unit-tests.rb

#!/usr/bin/env ruby

require 'xcodeproj'
require 'colored'

def insert_unit_testing_flag() 
  target_name = 'Your-Project-Name'
  project_path = '../Your-Project-Name.xcodeproj'
  unit_testing_identifier = "UNIT_TESTING"
  symbol_identifier = "-D"
  project = Xcodeproj::Project.open(project_path)
  target = project.targets.find { |target| target.to_s == target_name }
  puts target.name
  definitions = target.build_settings('Debug')['OTHER_SWIFT_FLAGS']
  if definitions.include? unit_testing_identifier
    puts "No operation.".yellow
  else 
    definitions << " #{symbol_identifier}"
    definitions << " #{unit_testing_identifier}"
    puts definitions.green
    project.save()
  end
end

def delete_unit_testing_flag() 
  target_name = 'Your-Project-Name'
  project_path = '../Your-Project-Name.xcodeproj'
  unit_testing_identifier = "UNIT_TESTING"
  symbol_identifier = "-D"
  project = Xcodeproj::Project.open(project_path)
  target = project.targets.find { |target| target.to_s == target_name }
  puts target.name
  definitions = target.build_settings('Debug')['OTHER_SWIFT_FLAGS']
  if definitions.include? unit_testing_identifier
    elements = definitions.split(" ")
    unit_testing_identifier_index = elements.index(unit_testing_identifier)
    symbol_identifier_index = unit_testing_identifier_index - 1
    symbol_identifier_element = elements.at(symbol_identifier_index)
    if symbol_identifier_element ==  symbol_identifier
      elements.delete(symbol_identifier)
    end
    elements.delete(unit_testing_identifier)
    definitions = elements.join(" ")
    puts definitions.green
    target.build_settings('Debug')['OTHER_SWIFT_FLAGS'] = definitions
    project.save()
  else 
    puts "No operation.".yellow
  end
end

argument = ARGV[0]

puts "#{argument}"

if argument == 'enable'
  insert_unit_testing_flag
elsif argument == 'disable'
  delete_unit_testing_flag
else 
 puts 'The parameter is error.'.red
end