ruby-on-rails - 方法 diff active/support ruby​​ 不工作

Question

我需要有关此方法的帮助我正在关注 codeschool 的 curse ruby​​ bits它向 ruby​​ 添加了一个名为 active_support 的库但这种方法对我不起作用我认为这个功能被破坏了我不确定

require 'active_support/all'
 {1 => 2}.diff(1 => 2)         # => {}
  {1 => 2}.diff(1 => 3)         # => {1 => 2}
  {}.diff(1 => 2)               # => {1 => 2}
  {1 => 2, 3 => 4}.diff(1 => 2) # => {3 => 4}

fernando@fernando:~/ruby$ ruby tweets.rb 
tweets.rb:2:in `<main>': undefined method `diff' for {1=>2}:Hash (NoMethodError)
fernando@fernando:~/ruby$ irb
irb(main):001:0> require 'active_support/all'
=> true
irb(main):002:0>  {1 => 2}.diff(1 => 2)         # => {}
NoMethodError: undefined method `diff' for {1=>2}:Hash
    from (irb):2
    from /usr/bin/irb:12:in `<main>'
irb(main):003:0>   {1 => 2}.diff(1 => 3)         # => {1 => 2}
NoMethodError: undefined method `diff' for {1=>2}:Hash
    from (irb):3
    from /usr/bin/irb:12:in `<main>'
irb(main):004:0>   {}.diff(1 => 2)               # => {1 => 2}
NoMethodError: undefined method `diff' for {}:Hash
    from (irb):4
    from /usr/bin/irb:12:in `<main>'
irb(main):005:0>   {1 => 2, 3 => 4}.diff(1 => 2) # => {3 => 4}
NoMethodError: undefined method `diff' for {1=>2, 3=>4}:Hash
    from (irb):5
    from /usr/bin/irb:12:in `<main>'

Answer 1

Rails 团队弃用了 ActiveSupport 中的 Hash#diff，转而使用 MiniTest#diff。参见 https://github.com/rails/rails/pull/8142 .

他们倾向于经常弃用某些东西(测试如此重要的另一个原因)。