Class: RuboCop::Cop::Style::EmptyLiteral

Inherits:
Base
  • Object
show all
Extended by:
AutoCorrector
Includes:
FrozenStringLiteral, RangeHelp, RuboCop::Cop::StringLiteralsHelp
Defined in:
lib/rubocop/cop/style/empty_literal.rb

Overview

Checks for the use of a method, the result of which would be a literal, like an empty array, hash, or string.

NOTE: When frozen string literals are enabled, ‘String.new` isn’t corrected to an empty string since the former is mutable and the latter would be frozen.

Examples:

# bad a = Array.new a = Array[] h = Hash.new h = Hash[] s = String.new # good a = [] h = {} s = ''

Constant Summary collapse

ARR_MSG = 
'Use array literal `[]` instead of `%<current>s`.'
HASH_MSG = 
'Use hash literal `{}` instead of `%<current>s`.'
STR_MSG = 
'Use string literal `%<prefer>s` instead of `String.new`.'
RESTRICT_ON_SEND = 
i[new [] Array Hash].freeze

Constants included from RangeHelp

RangeHelp::BYTE_ORDER_MARK, RangeHelp::NOT_GIVEN

Constants included from FrozenStringLiteral

FrozenStringLiteral::FROZEN_STRING_LITERAL_ENABLED

Instance Attribute Summary

Attributes inherited from Base

#config, #processed_source

Instance Method Summary collapse

Methods included from AutoCorrector

support_autocorrect?

Methods included from FrozenStringLiteral

frozen_string_literal_comment_exists?

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

#array_node(node) ⇒ Object 

 38
 
# File 'lib/rubocop/cop/style/empty_literal.rb', line 38 def_node_matcher :array_node, '(send (const {nil? cbase} :Array) :new (array)?)'

#array_with_block(node) ⇒ Object 

 47
 
# File 'lib/rubocop/cop/style/empty_literal.rb', line 47 def_node_matcher :array_with_block, '(block (send (const {nil? cbase} :Array) :new) args _)'

#array_with_index(node) ⇒ Object 

 58 59 60 61 62 63
 
# File 'lib/rubocop/cop/style/empty_literal.rb', line 58 def_node_matcher :array_with_index, "{\n (send (const {nil? cbase} :Array) :[])\n (send nil? :Array (array))\n}\n"

#hash_node(node) ⇒ Object 

 41
 
# File 'lib/rubocop/cop/style/empty_literal.rb', line 41 def_node_matcher :hash_node, '(send (const {nil? cbase} :Hash) :new)'

#hash_with_block(node) ⇒ Object 

 50 51 52 53 54 55
 
# File 'lib/rubocop/cop/style/empty_literal.rb', line 50 def_node_matcher :hash_with_block, "{\n (block (send (const {nil? cbase} :Hash) :new) args _)\n (numblock (send (const {nil? cbase} :Hash) :new) ...)\n}\n"

#hash_with_index(node) ⇒ Object 

 66 67 68 69 70 71
 
# File 'lib/rubocop/cop/style/empty_literal.rb', line 66 def_node_matcher :hash_with_index, "{\n (send (const {nil? cbase} :Hash) :[])\n (send nil? :Hash (array))\n}\n"

#on_send(node) ⇒ Object 

 73 74 75 76 77 78 79
 
# File 'lib/rubocop/cop/style/empty_literal.rb', line 73 def on_send(node) return unless (message = offense_message(node)) add_offense(node, message: message) do |corrector| corrector.replace(replacement_range(node), correction(node)) end end

#str_node(node) ⇒ Object 

 44
 
# File 'lib/rubocop/cop/style/empty_literal.rb', line 44 def_node_matcher :str_node, '(send (const {nil? cbase} :String) :new)'