class Minitest::Mock

def __call name, data # :nodoc:
  case data
  when Hash then
    "#{name}(#{data[:args].inspect[1..-2]}) => #{data[:retval].inspect}"
  else
    data.map { |d| __call name, d }.join ", "
  end
end

def expect(name, retval, args = [], &blk)
  name = name.to_sym
  if block_given?
    raise ArgumentError, "args ignored when block given" unless args.empty?
    @expected_calls[name] << { :retval => retval, :block => blk }
  else
    raise ArgumentError, "args must be an array" unless Array === args
    @expected_calls[name] << { :retval => retval, :args => args }
  end
  self
end

def initialize # :nodoc:
  @expected_calls = Hash.new { |calls, name| calls[name] = [] }
  @actual_calls   = Hash.new { |calls, name| calls[name] = [] }
end

def method_missing(sym, *args, &block) # :nodoc:
  unless @expected_calls.key?(sym) then
    raise NoMethodError, "unmocked method %p, expected one of %p" %
      [sym, @expected_calls.keys.sort_by(&:to_s)]
  end
  index = @actual_calls[sym].length
  expected_call = @expected_calls[sym][index]
  unless expected_call then
    raise MockExpectationError, "No more expects available for %p: %p" %
      [sym, args]
  end
  expected_args, retval, val_block =
    expected_call.values_at(:args, :retval, :block)
  if val_block then
    # keep "verify" happy
    @actual_calls[sym] << expected_call
    raise MockExpectationError, "mocked method %p failed block w/ %p" %
      [sym, args] unless val_block.call(*args, &block)
    return retval
  end
  if expected_args.size != args.size then
    raise ArgumentError, "mocked method %p expects %d arguments, got %d" %
      [sym, expected_args.size, args.size]
  end
  fully_matched = expected_args.zip(args).all? { |mod, a|
    mod === a or mod == a
  }
  unless fully_matched then
    raise MockExpectationError, "mocked method %p called with unexpected arguments %p" %
      [sym, args]
  end
  @actual_calls[sym] << {
    :retval => retval,
    :args => expected_args.zip(args).map { |mod, a| mod === a ? mod : a },
  }
  retval
end

def respond_to?(sym, include_private = false) # :nodoc:
  return true if @expected_calls.key? sym.to_sym
  __respond_to?(sym, include_private)
end

def verify
  @expected_calls.each do |name, calls|
    calls.each do |expected|
      msg1 = "expected #{__call name, expected}"
      msg2 = "#{msg1}, got [#{__call name, @actual_calls[name]}]"
      raise MockExpectationError, msg2 if
        @actual_calls.key?(name) and
        not @actual_calls[name].include?(expected)
      raise MockExpectationError, msg1 unless
        @actual_calls.key?(name) and
        @actual_calls[name].include?(expected)
    end
  end
  true
end