Class: RuboCop::Cop::Style::HashExcept

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

Overview

Checks for usages of ‘Hash#reject`, `Hash#select`, and `Hash#filter` methods that can be replaced with `Hash#except` method.

This cop should only be enabled on Ruby version 3.0 or higher. (‘Hash#except` was added in Ruby 3.0.)

For safe detection, it is limited to commonly used string and symbol comparisons when used ‘==`. And do not check `Hash#delete_if` and `Hash#keep_if` to change receiver object.

Examples:


# bad
{foo: 1, bar: 2, baz: 3}.reject {|k, v| k == :bar }
{foo: 1, bar: 2, baz: 3}.select {|k, v| k != :bar }
{foo: 1, bar: 2, baz: 3}.filter {|k, v| k != :bar }
{foo: 1, bar: 2, baz: 3}.reject {|k, v| k.eql?(:bar) }

# bad
{foo: 1, bar: 2, baz: 3}.reject {|k, v| %i[bar].include?(k) }
{foo: 1, bar: 2, baz: 3}.select {|k, v| !%i[bar].include?(k) }
{foo: 1, bar: 2, baz: 3}.filter {|k, v| !%i[bar].include?(k) }

# bad
{foo: 1, bar: 2, baz: 3}.reject {|k, v| !%i[bar].exclude?(k) }
{foo: 1, bar: 2, baz: 3}.select {|k, v| %i[bar].exclude?(k) }

# bad
{foo: 1, bar: 2, baz: 3}.reject {|k, v| k.in?(%i[bar]) }
{foo: 1, bar: 2, baz: 3}.select {|k, v| !k.in?(%i[bar]) }

# good
{foo: 1, bar: 2, baz: 3}.except(:bar)

Constant Summary collapse

MSG = 
'Use `%<prefer>s` instead.'
RESTRICT_ON_SEND = 
%i[reject select filter].freeze

Instance Attribute Summary

Attributes inherited from Base

#config, #processed_source

Instance Method Summary collapse

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 included from AutoCorrector

support_autocorrect?

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_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

#bad_method_with_active_support?(node) ⇒ Object 



71
72
73
74
75
76
77
78
79
80
81
82
83
84
 
# File 'lib/rubocop/cop/style/hash_except.rb', line 71

def_node_matcher :bad_method_with_active_support?, <<~PATTERN
  (block
    (send _ _)
    (args
      $(arg _)
      (arg _))
    {
      $(send
        _ {:== :!= :eql? :in? :include? :exclude?} _)
      (send
        $(send
          _ {:== :!= :eql? :in? :include? :exclude?} _) :!)
      })
PATTERN

#bad_method_with_poro?(node) ⇒ Object 



55
56
57
58
59
60
61
62
63
64
65
66
67
68
 
# File 'lib/rubocop/cop/style/hash_except.rb', line 55

def_node_matcher :bad_method_with_poro?, <<~PATTERN
  (block
    (call _ _)
    (args
      $(arg _)
      (arg _))
    {
      $(send
        _ {:== :!= :eql? :include?} _)
      (send
        $(send
          _ {:== :!= :eql? :include?} _) :!)
      })
PATTERN

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



86
87
88
89
90
91
92
93
94
95
96
97
98
99
 
# File 'lib/rubocop/cop/style/hash_except.rb', line 86

def on_send(node)
  block = node.parent
  return unless bad_method?(block) && semantically_except_method?(node, block)

  except_key = except_key(block)
  return if except_key.nil? || !safe_to_register_offense?(block, except_key)

  range = offense_range(node)
  preferred_method = "except(#{except_key_source(except_key)})"

  add_offense(range, message: format(MSG, prefer: preferred_method)) do |corrector|
    corrector.replace(range, preferred_method)
  end
end