Class: RuboCop::Cop::Style::ArrayJoin

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

Overview

Checks for uses of ‘*` as a substitute for `Array#join`. Using join is clearer about intent and more readable than overloading the `*` operator for string conversion.

Not all cases can be reliably checked, due to Ruby’s dynamic types, so we consider only cases when the first argument is an array literal or the second is a string literal.

Examples:


# bad
%w(foo bar baz) * ","

# good
%w(foo bar baz).join(",")

Constant Summary collapse

MSG = 
'Favor `Array#join` over `Array#*`.'
RESTRICT_ON_SEND = 
i[*].freeze

Instance Attribute Summary

Attributes inherited from Base

#config, #processed_source

Instance Method Summary collapse

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_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

#join_candidate?(node) ⇒ Object 



29
 
# File 'lib/rubocop/cop/style/array_join.rb', line 29

def_node_matcher :join_candidate?, '(send $array :* $str)'

#on_send(node) ⇒ Object 



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

def on_send(node)
  return unless (array, join_arg = join_candidate?(node))

  add_offense(node.loc.selector) do |corrector|
    corrector.replace(node, "#{array.source}.join(#{join_arg.source})")
  end
end