ruby - 重新定义单元测试的方法

Question

我在 ruby​​ 语法中不是那么严格，但是如果我在学习它时理解了一些东西，你可以做任何事情，没有任何限制，假设我有一个类方法，我想在单元测试中重新定义它以隔离我的东西正在测试，我该怎么做？假设类名是 foo，实例方法是 bar。

Answer 1

Test::Redef is a gem designed to do exactly this.

test "some method on Foo should be called because under normal circumstances it something useful like send network traffic" do
  Test::Redef.rd(
    'Foo#bar'  => proc {|args| puts 'new behavior goes here!'},
    'Foo#baz'  => :empty,   # same as => proc { }
    'Foo#quux' => :wiretap, # no behavior change but you get invocation tracking
    'Foo.blat' => :empty,   # class method
  ) do |rd|

    # code under test


    assert_equal [['invocation 1 arg 1', 'invocation 1 arg 2'], 
                  ['invocation 2 arg 1'],
                 ], rd[:bar].args, 'Foo#bar was called with the right arguments'
  end

  # now all methods are back to normal
end