Class: RuboCop::Cop::Style::StructInheritance

Inherits:
Base
  • Object
show all
Extended by:
AutoCorrector
Includes:
RangeHelp
Defined in:
lib/rubocop/cop/style/struct_inheritance.rb

Overview

Checks for inheritance from Struct.new.

Examples:

# bad
class Person < Struct.new(:first_name, :last_name)
  def age
    42
  end
end

# good
Person = Struct.new(:first_name, :last_name) do
  def age
    42
  end
end

Cop Safety Information:

  • Autocorrection is unsafe because it will change the inheritance tree (e.g. return value of Module#ancestors) of the constant.

Constant Summary collapse

MSG =
"Don't extend an instance initialized by `Struct.new`. " \
'Use a block to customize the struct.'

Constants inherited from Base

Base::RESTRICT_ON_SEND

Instance Attribute Summary

Attributes inherited from Base

#config, #processed_source

Instance Method Summary collapse

Methods included from AutoCorrector

support_autocorrect?

Methods inherited from Base

#active_support_extensions_enabled?, #add_global_offense, #add_offense, autocorrect_incompatible_with, badge, #begin_investigation, callbacks_needed, #callbacks_needed, #config_to_allow_offenses, #config_to_allow_offenses=, #cop_config, cop_name, #cop_name, department, documentation_url, exclude_from_registry, #excluded_file?, #external_dependency_checksum, inherited, #initialize, #inspect, joining_forces, lint?, match?, #message, #offenses, #on_investigation_end, #on_new_investigation, #on_other_file, #parse, #ready, #relevant_file?, support_autocorrect?, support_multiple_source?, #target_rails_version, #target_ruby_version

Methods included from ExcludeLimit

#exclude_limit

Methods included from AutocorrectLogic

#autocorrect?, #autocorrect_enabled?, #autocorrect_requested?, #autocorrect_with_disable_uncorrectable?, #correctable?, #disable_uncorrectable?, #safe_autocorrect?

Methods included from IgnoredNode

#ignore_node, #ignored_node?, #part_of_ignored_node?

Methods included from Util

silence_warnings

Constructor Details

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

Instance Method Details

#on_class(node) ⇒ Object



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# File 'lib/rubocop/cop/style/struct_inheritance.rb', line 33

def on_class(node)
  return unless struct_constructor?(node.parent_class)

  add_offense(node.parent_class.source_range) do |corrector|
    corrector.remove(range_with_surrounding_space(node.loc.keyword, newlines: false))
    corrector.replace(node.loc.operator, '=')

    correct_parent(node.parent_class, corrector)
  end
end

#struct_constructor?(node) ⇒ Object



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# File 'lib/rubocop/cop/style/struct_inheritance.rb', line 45

def_node_matcher :struct_constructor?, <<~PATTERN
  {(send (const {nil? cbase} :Struct) :new ...)
   (block (send (const {nil? cbase} :Struct) :new ...) ...)}
PATTERN