Class: RuboCop::Cop::Lint::EachWithObjectArgument

Inherits:
Cop
  • Object
show all
Defined in:
lib/rubocop/cop/lint/each_with_object_argument.rb

Overview

This cop checks if each_with_object is called with an immutable argument. Since the argument is the object that the given block shall make calls on to build something based on the enumerable that each_with_object iterates over, an immutable argument makes no sense. It's definitely a bug.

Examples:


sum = numbers.each_with_object(0) { |e, a| a += e }

Constant Summary collapse

MSG =
'The argument to each_with_object can not be immutable.'

Constants included from Util

Util::ASGN_NODES, Util::EQUALS_ASGN_NODES, Util::OPERATOR_METHODS, Util::PROC_NEW_NODE, Util::SHORTHAND_ASGN_NODES

Instance Attribute Summary

Attributes inherited from Cop

#config, #corrections, #offenses, #processed_source

Instance Method Summary collapse

Methods inherited from Cop

#add_offense, all, #config_to_allow_offenses, #config_to_allow_offenses=, #cop_config, cop_name, #cop_name, cop_type, #correct, #debug?, #display_cop_names?, #display_style_guide?, #excluded_file?, inherited, #initialize, #join_force?, lint?, match?, #message, non_rails, qualified_cop_name, rails?, #reference_url, #relevant_file?, #style_guide_url

Methods included from AutocorrectLogic

#autocorrect?, #autocorrect_enabled?, #autocorrect_requested?, #support_autocorrect?

Methods included from IgnoredNode

#ignore_node, #ignored_node?, #part_of_ignored_node?

Methods included from Util

begins_its_line?, block_length, command?, comment_line?, const_name, directions, first_part_of_call_chain, lambda?, lambda_or_proc?, line_range, move_pos, numeric_range_size, on_node, operator?, parentheses?, proc?, range_with_surrounding_comma, range_with_surrounding_space, source_range, strip_quotes, within_node?

Methods included from PathUtil

hidden?, issue_deprecation_warning, match_path?, relative_path

Constructor Details

This class inherits a constructor from RuboCop::Cop::Cop

Instance Method Details

#on_send(node) ⇒ Object



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# File 'lib/rubocop/cop/lint/each_with_object_argument.rb', line 18

def on_send(node)
  _receiver, method_name, *args = *node
  return unless method_name == :each_with_object
  return unless args.length == 1

  arg = args.first
  add_offense(node, :expression) if arg.int_type? || arg.float_type?
end