我试图使用RSpec的参数匹配特性来确保方法被正确的hash参数调用。不幸的是，RSpec似乎不允许我说receive(:foo).with(instance_of(MyClass) => :bar, instance_of(MyClass) => :baz)之类的话，大概是因为参数是一个hash。
我尝试使用including_hash匹配器来表示receive(:foo).with(hash_including(instance_of(MyClass) => :bar, instance_of(MyClass) => :baz))，但这也不起作用。
这里有一个再生产的问题：

# !/usr/bin/env ruby

require "rspec"

class Account
  def initialize(logger)
    @logger = logger
  end

  def open_with_hash_arg
    pipe_r, pipe_w = IO.pipe
    @logger.account_opened(pipe_r => :read, pipe_w => :write)
  end

  def open_with_flat_args
    pipe_r, pipe_w = IO.pipe
    @logger.account_opened(pipe_r, pipe_w)
  end
end

describe Account do
  it "fails with hash arg" do
    logger = double("Logger")
    expect(logger).to receive(:account_opened).with(instance_of(IO) => :read, instance_of(IO) => :write)
    account = Account.new(logger)
    account.open_with_hash_arg
  end

  it "succeeds with flat args" do
    logger = double("Logger")
    expect(logger).to receive(:account_opened).with(instance_of(IO), instance_of(IO))
    account = Account.new(logger)
    account.open_with_flat_args
  end
end

下面是此程序的输出：

$ rspec ./tmp.rb
F.

Failures:

  1) Account fails with hash arg
     Failure/Error: @logger.account_opened(pipe_r => :read, pipe_w => :write)

       #<Double "Logger"> received :account_opened with unexpected arguments
         expected: ({an_instance_of(IO)=>:read, an_instance_of(IO)=>:write})
              got: ({#<IO:fd 5>=>:read, #<IO:fd 6>=>:write})
       Diff:
       @@ -1 +1 @@
       -[{an_instance_of(IO)=>:read, an_instance_of(IO)=>:write}]
       +[{#<IO:fd 5>=>:read, #<IO:fd 6>=>:write}]

     # ./tmp.rb:12:in `open_with_hash_arg'
     # ./tmp.rb:26:in `block (2 levels) in <top (required)>'

Finished in 0.01154 seconds (files took 0.04986 seconds to load)
2 examples, 1 failure

Failed examples:

rspec ./tmp.rb:22 # Account fails with hash arg

我如何使用RSpec来测试一个方法是用一个散列参数调用的，其中的键是某个类的示例？
请注意，我使用的是RSpec 3.11版