class RSpec::Matchers::BuiltIn::DynamicPredicate

def description
  "#{method_description}#{args_to_sentence}"
end

def does_not_match?(actual, &block)
  @actual = actual
  @block ||= block
  predicate_accessible? && predicate_matches?(false)
end

def expectation_of(value)
  if RSpec::Expectations.configuration.strict_predicate_matchers?
    "return #{value}"
  elsif value
    "be truthy"
  else
    "be falsey"
  end
end

def failure_message
  failure_message_expecting(true)
end

def failure_message_expecting(value)
  validity_message ||
    "expected `#{actual_formatted}.#{predicate}#{args_to_s}` to #{expectation_of value}, got #{description_of @predicate_result}"
end

def failure_message_when_negated
  failure_message_expecting(false)
end

def failure_to_respond_explanation
  if private_predicate?
    " but `#{predicate}` is a private method"
  end
end

def initialize(method_name, *args, &block)
  @method_name, @args, @block = method_name, args, block
end

def matches?(actual, &block)
  @actual = actual
  @block ||= block
  predicate_accessible? && predicate_matches?
end

def method_description
  EnglishPhrasing.split_words(@method_name)
end

def methods_include?(method)
  @actual.methods.include?(method.to_s)
end

def methods_include?(method)
  @actual.methods.include?(method)
end

def predicate_accessible?
  really_responds_to?(predicate)
end

def predicate_matches?(value=true)
  if RSpec::Expectations.configuration.strict_predicate_matchers?
    value == predicate_result
  else
    value == !!predicate_result
  end
end

def predicate_method_name
  predicate
end

def predicate_result
  @predicate_result = actual.__send__(predicate_method_name, *@args, &@block)
end

def private_predicate?
  @actual.private_methods.include? predicate.to_s
end

def private_predicate?
  @actual.private_methods.include? predicate
end

def really_responds_to?(method)
  if RSpec::Mocks::Double === @actual
    @actual.respond_to?(method) && methods_include?(method)
  else
    @actual.respond_to?(method)
  end
end

def really_responds_to?(method)
  @actual.respond_to?(method)
end

def root
  # On 1.9, there appears to be a bug where String#match can return `false`
  # rather than the match data object. Changing to Regex#match appears to
  # work around this bug. For an example of this bug, see:
  # https://travis-ci.org/rspec/rspec-expectations/jobs/27549635
  self.class::REGEX.match(@method_name.to_s).captures.first
end

def validity_message
  return nil if predicate_accessible?
  "expected #{actual_formatted} to respond to `#{predicate}`#{failure_to_respond_explanation}"
end