Class: RuboCop::Cop::Performance::StringIdentifierArgument

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

Overview

Identifies places where string identifier argument can be replaced by symbol identifier argument. It prevents the redundancy of the internal string-to-symbol conversion.

This cop targets methods that take identifier (e.g. method name) argument and the following examples are parts of it.

Examples:


# bad
send('do_something')
attr_accessor 'do_something'
instance_variable_get('@ivar')

# good
send(:do_something)
attr_accessor :do_something
instance_variable_get(:@ivar)

Constant Summary collapse

MSG = 
'Use `%<symbol_arg>s` instead of `%<string_arg>s`.'
COMMAND_METHODS = 
%i[
  alias_method attr_accessor attr_reader attr_writer autoload autoload? private private_constant
  protected public public_constant module_function
].freeze
RESTRICT_ON_SEND =

NOTE: ‘attr` method is not included in this list as it can cause false positives in Nokogiri API. And `attr` may not be used because `Style/Attr` registers an offense. github.com/rubocop/rubocop-performance/issues/278

(%i[
  class_variable_defined? const_defined? const_get const_set const_source_location
  define_method instance_method method_defined? private_class_method? private_method_defined?
  protected_method_defined? public_class_method public_instance_method public_method_defined?
  remove_class_variable remove_method undef_method class_variable_get class_variable_set
  deprecate_constant remove_const ruby2_keywords define_singleton_method instance_variable_defined?
  instance_variable_get instance_variable_set method public_method public_send remove_instance_variable
  respond_to? send singleton_method __send__
] + COMMAND_METHODS).freeze

Instance Method Summary collapse

Instance Method Details

#on_send(node) ⇒ Object 



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# File 'lib/rubocop/cop/performance/string_identifier_argument.rb', line 48

def on_send(node)
  return if COMMAND_METHODS.include?(node.method_name) && node.receiver
  return unless (first_argument = node.first_argument)
  return unless first_argument.str_type?

  first_argument_value = first_argument.value
  return if first_argument_value.include?(' ') || first_argument_value.include?('::')

  replacement = first_argument_value.to_sym.inspect

  message = format(MSG, symbol_arg: replacement, string_arg: first_argument.source)

  add_offense(first_argument, message: message) do |corrector|
    corrector.replace(first_argument, replacement)
  end
end