class RSpec::Matchers::BuiltIn::RespondTo

def argument
  self
end

def description
  "respond to #{pp_names}#{with_arity}"
end

def does_not_match?(actual)
  find_failing_method_names(actual, :select).empty?
end

def failure_message
  "expected #{actual_formatted} to respond to #{@failing_method_names.map { |name| description_of(name) }.join(', ')}#{with_arity}"
end

def failure_message_when_negated
  failure_message.sub(/to respond to/, 'not to respond to')
end

def find_failing_method_names(actual, filter_method)
  @actual = actual
  @failing_method_names = @names.__send__(filter_method) do |name|
    @actual.respond_to?(name) && matches_arity?(actual, name)
  end
end

def ignoring_method_signature_failure!
  @ignoring_method_signature_failure = true
end

def initialize(*names)
  @names = names
  @expected_arity = nil
  @expected_keywords = []
  @ignoring_method_signature_failure = false
  @unlimited_arguments = nil
  @arbitrary_keywords = nil
end

def matches?(actual)
  find_failing_method_names(actual, :reject).empty?
end

def matches_arity?(actual, name)
  ArityCheck.new(@expected_arity, @expected_keywords, @arbitrary_keywords, @unlimited_arguments).matches?(actual, name)
rescue NameError
  return true if @ignoring_method_signature_failure
  raise ArgumentError, "The #{matcher_name} matcher requires that " \
                       "the actual object define the method(s) in " \
                       "order to check arity, but the method " \
                       "`#{name}` is not defined. Remove the arity " \
                       "check or define the method to continue."
end

def pp_names
  @names.length == 1 ? "##{@names.first}" : description_of(@names)
end

def with(n)
  @expected_arity = n
  self
end

def with_any_keywords
  @arbitrary_keywords = true
  self
end

def with_arity
  str = ''.dup
  str << " with #{with_arity_string}" if @expected_arity
  str << " #{str.length == 0 ? 'with' : 'and'} #{with_keywords_string}" if @expected_keywords && @expected_keywords.count > 0
  str << " #{str.length == 0 ? 'with' : 'and'} unlimited arguments" if @unlimited_arguments
  str << " #{str.length == 0 ? 'with' : 'and'} any keywords" if @arbitrary_keywords
  str
end

def with_arity_string
  "#{@expected_arity} argument#{@expected_arity == 1 ? '' : 's'}"
end

def with_keywords(*keywords)
  @expected_keywords = keywords
  self
end

def with_keywords_string
  kw_str = case @expected_keywords.count
           when 1
             @expected_keywords.first.inspect
           when 2
             @expected_keywords.map(&:inspect).join(' and ')
           else
             "#{@expected_keywords[0...-1].map(&:inspect).join(', ')}, and #{@expected_keywords.last.inspect}"
           end
  "keyword#{@expected_keywords.count == 1 ? '' : 's'} #{kw_str}"
end

def with_unlimited_arguments
  @unlimited_arguments = true
  self
end