Class: RuboCop::Cop::Lint::UselessTimes

Inherits:
Base
  • Object
show all
Extended by:
AutoCorrector
Includes:
RangeHelp
Defined in:
lib/rubocop/cop/lint/useless_times.rb

Overview

This cop checks for uses of `Integer#times` that will never yield (when the integer <= 0) or that will only ever yield once (`1.times`).

This cop is marked as unsafe as `times` returns its receiver, which is usually OK, but might change behavior.

Examples:

# bad
-5.times { do_something }
0.times { do_something }
1.times { do_something  }
1.times { |i| do_something(i) }

# good
do_something
do_something(1)

Constant Summary collapse

MSG =
'Useless call to `%<count>i.times` detected.'
RESTRICT_ON_SEND =
%i[times].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

#add_global_offense, #add_offense, autocorrect_incompatible_with, badge, #callbacks_needed, callbacks_needed, #config_to_allow_offenses, #config_to_allow_offenses=, #cop_config, #cop_name, cop_name, department, documentation_url, exclude_from_registry, #excluded_file?, #external_dependency_checksum, inherited, #initialize, joining_forces, lint?, match?, #message, #offenses, #on_investigation_end, #on_new_investigation, #on_other_file, #parse, #ready, #relevant_file?, support_autocorrect?, support_multiple_source?, #target_rails_version, #target_ruby_version

Methods included from ExcludeLimit

#exclude_limit

Methods included from AutocorrectLogic

#autocorrect?, #autocorrect_enabled?, #autocorrect_requested?, #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

#block_arg(node) ⇒ Object


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# File 'lib/rubocop/cop/lint/useless_times.rb', line 36

def_node_matcher :block_arg, <<~PATTERN
  (block _ (args (arg $_)) ...)
PATTERN

#block_reassigns_arg?(node) ⇒ Object


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# File 'lib/rubocop/cop/lint/useless_times.rb', line 41

def_node_search :block_reassigns_arg?, <<~PATTERN
  (lvasgn %)
PATTERN

#on_send(node) ⇒ Object


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# File 'lib/rubocop/cop/lint/useless_times.rb', line 45

def on_send(node)
  return unless (count, proc_name = times_call?(node))
  return if count > 1

  # Get the block node if applicable
  node = node.block_node if node.block_literal?

  add_offense(node, message: format(MSG, count: count)) do |corrector|
    next unless own_line?(node)

    if never_process?(count, node)
      remove_node(corrector, node)
    elsif !proc_name.empty?
      autocorrect_block_pass(corrector, node, proc_name)
    else
      autocorrect_block(corrector, node)
    end
  end
end

#times_call?(node) ⇒ Object


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# File 'lib/rubocop/cop/lint/useless_times.rb', line 31

def_node_matcher :times_call?, <<~PATTERN
  (send (int $_) :times (block-pass (sym $_))?)
PATTERN