Class: Rubocop::Cop::Style::EmptyLiteral

Inherits:
Cop
  • Object
show all
Defined in:
lib/rubocop/cop/style/empty_literal.rb

Overview

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

Constant Summary collapse

ARR_MSG = 
'Use array literal [] instead of Array.new.'
HASH_MSG = 
'Use hash literal {} instead of Hash.new.'
STR_MSG = 
"Use string literal '' instead of String.new."
ARRAY_NODE =

Empty array node

(send (const nil :Array) :new)

s(:send, s(:const, nil, :Array), :new)
HASH_NODE =

Empty hash node

(send (const nil :Hash) :new)

s(:send, s(:const, nil, :Hash), :new)
STR_NODE =

Empty string node

(send (const nil :String) :new)

s(:send, s(:const, nil, :String), :new)

Constants inherited from Cop

Cop::OPERATOR_METHODS

Constants included from Util

Util::PROC_NEW_NODE

Instance Attribute Summary

Attributes inherited from Cop

#config, #corrections, #offences, #processed_source

Instance Method Summary collapse

Methods inherited from Cop

#add_offence, all, #autocorrect?, #config_to_allow_offences, #config_to_allow_offences=, #cop_config, cop_name, #cop_name, cop_type, #debug?, #exclude_file?, #exclude_paths, #ignore_node, #include_file?, #include_paths, inherited, #initialize, lint?, #message, non_rails, rails?, #relevant_file?, style?, #support_autocorrect?

Methods included from Util

block_length, command?, comment_line?, const_name, first_part_of_call_chain, lambda?, lambda_or_proc?, line_range, on_node, proc?, range_with_surrounding_space, source_range, strip_quotes

Constructor Details

This class inherits a constructor from Rubocop::Cop::Cop

Instance Method Details

#autocorrect(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/empty_literal.rb', line 47

def autocorrect(node)
  @corrections << lambda do |corrector|
    name = case node
           when ARRAY_NODE then '[]'
           when HASH_NODE then '{}'
           when STR_NODE then "''"
           end
    corrector.replace(node.loc.expression, name)
  end
end

#on_send(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/empty_literal.rb', line 31

def on_send(node)
  return if part_of_ignored_node?(node)

  case node
  when ARRAY_NODE
    add_offence(node, :expression, ARR_MSG)
  when HASH_NODE
    add_offence(node, :expression, HASH_MSG)
  when STR_NODE
    add_offence(node, :expression, STR_MSG)
  end
end