Class: RuboCop::Cop::Style::EvenOdd

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

Overview

This cop checks for places where `Integer#even?` or `Integer#odd?` can be used.

Examples:


# bad
if x % 2 == 0
end

# good
if x.even?
end

Constant Summary collapse

MSG =
'Replace with `Integer#%<method>s?`.'
RESTRICT_ON_SEND =
%i[== !=].freeze

Instance Attribute Summary

Attributes inherited from Base

#config, #processed_source

Instance Method Summary collapse

Methods included from AutoCorrector

support_autocorrect?

Methods inherited from Base

#add_global_offense, #add_offense, autocorrect_incompatible_with, badge, #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, 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?, #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

#even_odd_candidate?(node) ⇒ Object


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# File 'lib/rubocop/cop/style/even_odd.rb', line 25

def_node_matcher :even_odd_candidate?, <<~PATTERN
  (send
    {(send $_ :% (int 2))
     (begin (send $_ :% (int 2)))}
    ${:== :!=}
    (int ${0 1}))
PATTERN

#on_send(node) ⇒ Object


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

def on_send(node)
  even_odd_candidate?(node) do |base_number, method, arg|
    replacement_method = replacement_method(arg, method)
    add_offense(node, message: format(MSG, method: replacement_method)) do |corrector|
      correction = "#{base_number.source}.#{replacement_method}?"
      corrector.replace(node, correction)
    end
  end
end