class_length.rb

# frozen_string_literal: true

module RuboCop
  module Cop
    module Metrics
      # This cop checks if the length a class exceeds some maximum value.
      # Comment lines can optionally be ignored.
      # The maximum allowed length is configurable.
      #
      # You can set literals you want to fold with `CountAsOne`.
      # Available are: 'array', 'hash', and 'heredoc'. Each literal
      # will be counted as one line regardless of its actual size.
      #
      # @example CountAsOne: ['array', 'heredoc']
      #
      #   class Foo
      #     ARRAY = [         # +1
      #       1,
      #       2
      #     ]
      #
      #     HASH = {          # +3
      #       key: 'value'
      #     }
      #
      #     MSG = <<~HEREDOC  # +1
      #       Heredoc
      #       content.
      #     HEREDOC
      #   end                 # 5 points
      #
      #
      # NOTE: This cop also applies for `Struct` definitions.
      class ClassLength < Base
        include CodeLength

        def on_class(node)
          check_code_length(node)
        end

        def on_casgn(node)
          _scope, _name, block_node = *node
          check_code_length(node) if block_node.class_definition?
        end

        private

        def message(length, max_length)
          format('Class has too many lines. [%<length>d/%<max>d]',
                 length: length,
                 max: max_length)
        end
      end
    end
  end
end