🍒本 4章の例題

convert_rgb.rb

def to_hex(r, g, b)
  [r, g, b].inject('#') do |hex, n|
    hex + n.to_s(16).rjust(2, '0')
  end
end

def to_ints(hex)
  r, g, b = hex[1..2], hex[3..4], hex[5..6]
  [r, g, b].map(&:hex)
end

rgb_test.rb

require 'minitest/autorun'
require './lib/convert_rgb'

class RgbTest < Minitest::Test
  def test_to_hex
    assert_equal '#000000', to_hex(0, 0, 0)
    assert_equal '#ffffff', to_hex(255, 255, 255)
    assert_equal '#043c78', to_hex(4, 60, 120)
  end

  def test_to_ints
    assert_equal [0, 0, 0], to_ints('#000000')
    assert_equal [255, 255, 255], to_ints('#ffffff')
    # assert_equal '#043c78', to_hex(4, 60, 120)
  end
end