Class: RuboCop::Cop::Style::MutableConstant

Inherits:

Cop

• Object
• Cop
• RuboCop::Cop::Style::MutableConstant

Defined in:

lib/rubocop/cop/style/mutable_constant.rb

Overview

This cop checks whether some constant value isn't a mutable literal (e.g. array or hash).

Examples:

# bad
CONST = [1, 2, 3]

# good
CONST = [1, 2, 3].freeze

Constant Summary

MSG =

'Freeze mutable objects assigned to constants.'

MUTABLE_TYPES =

[:array, :hash, :str, :dstr].freeze

Constants included from Util

Util::ASGN_NODES, Util::BASIC_LITERALS, Util::EQUALS_ASGN_NODES, Util::LITERALS, 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

• #autocorrect(node) ⇒ Object
• #on_casgn(node) ⇒ Object

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?, #details, #display_cop_names?, #display_style_guide?, #excluded_file?, #extra_details?, inherited, #initialize, #join_force?, lint?, match?, #message, non_rails, qualified_cop_name, rails?, #reference_url, #relevant_file?, #style_guide_url

Methods included from NodePattern::Macros

#def_node_matcher, #def_node_search

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

#autocorrect(node) ⇒ Object

# File 'lib/rubocop/cop/style/mutable_constant.rb', line 28

def autocorrect(node)
  expr = node.loc.expression
  ->(corrector) { corrector.replace(expr, "#{expr.source}.freeze") }
end

#on_casgn(node) ⇒ Object

# File 'lib/rubocop/cop/style/mutable_constant.rb', line 20

def on_casgn(node)
  _scope, _const_name, value = *node

  return if value && !MUTABLE_TYPES.include?(value.type)

  add_offense(value, :expression)
end