Class: RuboCop::Cop::Style::ArrayIntersect

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

Overview

In Ruby 3.1, ‘Array#intersect?` has been added.

This cop identifies places where:

  • ‘(array1 & array2).any?`

  • ‘(array1.intersection(array2)).any?`

  • ‘array1.any? { |elem| array2.member?(elem) }`

  • ‘(array1 & array2).count > 0`

  • ‘(array1 & array2).size > 0`

can be replaced with ‘array1.intersect?(array2)`.

‘array1.intersect?(array2)` is faster and more readable.

In cases like the following, compatibility is not ensured, so it will not be detected when using block argument.

source,ruby

([1] & [1,2]).any? { |x| false } # => false [1].intersect?() { |x| false } # => true

NOTE: Although ‘Array#intersection` can take zero or multiple arguments, only cases where exactly one argument is provided can be replaced with `Array#intersect?` and are handled by this cop.

Examples:

# bad
(array1 & array2).any?
(array1 & array2).empty?
(array1 & array2).none?

# bad
array1.intersection(array2).any?
array1.intersection(array2).empty?
array1.intersection(array2).none?

# bad
array1.any? { |elem| array2.member?(elem) }
array1.none? { |elem| array2.member?(elem) }

# good
array1.intersect?(array2)
!array1.intersect?(array2)

# bad
(array1 & array2).count > 0
(array1 & array2).count.positive?
(array1 & array2).count != 0

(array1 & array2).count == 0
(array1 & array2).count.zero?

# good
array1.intersect?(array2)

!array1.intersect?(array2)

AllCops:ActiveSupportExtensionsEnabled: false (default)

# good
(array1 & array2).present?
(array1 & array2).blank?

AllCops:ActiveSupportExtensionsEnabled: true

# bad
(array1 & array2).present?
(array1 & array2).blank?

# good
array1.intersect?(array2)
!array1.intersect?(array2)

Constant Summary collapse

PREDICATES = 
%i[any? empty? none?].to_set.freeze
ACTIVE_SUPPORT_PREDICATES = 
(PREDICATES + %i[present? blank?]).freeze
ARRAY_SIZE_METHODS = 
%i[count length size].to_set.freeze
MSG = 
'Use `%<replacement>s` instead of `%<existing>s`.'
STRAIGHT_METHODS = 
%i[present? any? > positive? !=].freeze
NEGATED_METHODS = 
%i[blank? empty? none? == zero?].freeze
RESTRICT_ON_SEND = 
(STRAIGHT_METHODS + NEGATED_METHODS).freeze

Instance Attribute Summary

Attributes inherited from Base

#config, #processed_source

Instance Method Summary collapse

Methods included from AutoCorrector

support_autocorrect?

Methods included from TargetRubyVersion

maximum_target_ruby_version, minimum_target_ruby_version, required_maximum_ruby_version, required_minimum_ruby_version, support_target_ruby_version?

Methods inherited from Base

#active_support_extensions_enabled?, #add_global_offense, #add_offense, #always_autocorrect?, autocorrect_incompatible_with, badge, #begin_investigation, #callbacks_needed, callbacks_needed, #config_to_allow_offenses, #config_to_allow_offenses=, #contextual_autocorrect?, #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, #parser_engine, #ready, #relevant_file?, requires_gem, #string_literals_frozen_by_default?, support_autocorrect?, support_multiple_source?, #target_gem_version, #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

#any_none_block_intersection(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/array_intersect.rb', line 119

def_node_matcher :any_none_block_intersection, <<~PATTERN
  {
    (block
      (call $_receiver ${:any? :none?})
      (args (arg _key))
      (send $_argument :member? (lvar _key))
    )
    (numblock
      (call $_receiver ${:any? :none?}) 1
      (send $_argument :member? (lvar :_1))
    )
    (itblock
      (call $_receiver ${:any? :none?}) :it
      (send $_argument :member? (lvar :it))
    )
  }
PATTERN

#bad_intersection_check?(node, predicates) ⇒ Object 



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# File 'lib/rubocop/cop/style/array_intersect.rb', line 94

def_node_matcher :bad_intersection_check?, <<~PATTERN
  $(call
    {
      (begin (send $_ :& $_))
      (call $_ :intersection $_)
    }
    $%1
  )
PATTERN

#intersection_size_check?(node, predicates) ⇒ Object 



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# File 'lib/rubocop/cop/style/array_intersect.rb', line 105

def_node_matcher :intersection_size_check?, <<~PATTERN
  (call
    $(call
      {
        (begin (send $_ :& $_))
        (call $_ :intersection $_)
      }
      %ARRAY_SIZE_METHODS
    )
    {$:> (int 0) | $:positive? | $:!= (int 0) | $:== (int 0) | $:zero?}
  )
PATTERN

#on_block(node) ⇒ Object Also known as: on_numblock, on_itblock 



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# File 'lib/rubocop/cop/style/array_intersect.rb', line 154

def on_block(node)
  return unless (receiver, method_name, argument = any_none_block_intersection(node))

  dot = node.send_node.loc.dot.source
  bang = method_name == :any? ? '' : '!'
  replacement = "#{bang}#{receiver.source}#{dot}intersect?(#{argument.source})"

  register_offense(node, replacement)
end

#on_send(node) ⇒ Object Also known as: on_csend 



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# File 'lib/rubocop/cop/style/array_intersect.rb', line 142

def on_send(node)
  return if node.block_literal?
  return unless (dot_node, receiver, argument, method_name = bad_intersection?(node))

  dot = dot_node.loc.dot.source
  bang = straight?(method_name) ? '' : '!'
  replacement = "#{bang}#{receiver.source}#{dot}intersect?(#{argument.source})"

  register_offense(node, replacement)
end