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')
respond_to?("string_#{interpolation}")

# good
send(:do_something)
attr_accessor :do_something
instance_variable_get(:@ivar)
respond_to?(:"string_#{interpolation}")

# good - these methods don't support namespaced symbols
const_get("#{module_path}::Base")
const_source_location("#{module_path}::Base")
const_defined?("#{module_path}::Base")

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
INTERPOLATION_IGNORE_METHODS = 
%i[const_get const_source_location const_defined?].freeze
TWO_ARGUMENTS_METHOD = 
:alias_method
MULTIPLE_ARGUMENTS_METHODS = 
%i[
  attr_accessor attr_reader attr_writer 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_set
  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 + INTERPOLATION_IGNORE_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 64

def on_send(node)
  return if COMMAND_METHODS.include?(node.method_name) && node.receiver

  string_arguments(node).each do |string_argument|
    string_argument_value = string_argument.value
    next if string_argument_value.include?(' ') || string_argument_value.include?('::')

    register_offense(string_argument, string_argument_value)
  end
end