Class: RuboCop::Cop::Lint::DisjunctiveAssignmentInConstructor

Inherits:
Base
  • Object
show all
Extended by:
AutoCorrector
Defined in:
lib/rubocop/cop/lint/disjunctive_assignment_in_constructor.rb

Overview

Checks constructors for disjunctive assignments (||=) that should be plain assignments.

So far, this cop is only concerned with disjunctive assignment of instance variables.

In ruby, an instance variable is nil until a value is assigned, so the disjunction is unnecessary. A plain assignment has the same effect.

Examples:

# bad
def initialize
  @x ||= 1
end

# good
def initialize
  @x = 1
end

Cop Safety Information:

  • This cop is unsafe because it can register a false positive when a method is redefined in a subclass that calls super. For example:

    class Base
      def initialize
        @config ||= 'base'
      end
    end
    
    class Derived < Base
      def initialize
        @config = 'derived'
        super
      end
    end

    Without the disjunctive assignment, Derived will be unable to override the value for @config.

Constant Summary collapse

MSG =
'Unnecessary disjunctive assignment. Use plain assignment.'

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_def(node) ⇒ Object



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# File 'lib/rubocop/cop/lint/disjunctive_assignment_in_constructor.rb', line 53

def on_def(node)
  check(node)
end