lib/rubocop/cop/style/class_check.rb


# encoding: utf-8

module RuboCop
  module Cop
    module Style
      # This cop enforces consistent use of `Object#is_a?` or `Object#kind_of?`.
      class ClassCheck < Cop
        include ConfigurableEnforcedStyle

        MSG = 'Prefer `Object#%s` over `Object#%s`.'

        def on_send(node)
          _receiver, method_name, *_args = *node
          return unless [:is_a?,
                         :kind_of?].include?(method_name)

          return if style == method_name
          add_offense(node, :selector)
        end

        def message(node)
          _receiver, method_name, *_args = *node

          if method_name == :is_a?
            format(MSG, 'kind_of?', 'is_a?')
          else
            format(MSG, 'is_a?', 'kind_of?')
          end
        end

        def autocorrect(node)
          _receiver, method_name, *_args = *node

          lambda do |corrector|
            corrector.replace(node.loc.selector,
                              method_name == :is_a? ? 'kind_of?' : 'is_a?')
          end
        end
      end
    end
  end
end