Class: RuboCop::Cop::Lint::NextWithoutAccumulator

Inherits:
Base
  • Object
show all
Defined in:
lib/rubocop/cop/lint/next_without_accumulator.rb

Overview

Don't omit the accumulator when calling `next` in a `reduce` block.

Examples:


# bad

result = (1..4).reduce(0) do |acc, i|
  next if i.odd?
  acc + i
end

# good

result = (1..4).reduce(0) do |acc, i|
  next acc if i.odd?
  acc + i
end

Constant Summary collapse

MSG = 
'Use `next` with an accumulator argument in a `reduce`.'

Constants inherited from Base

Base::RESTRICT_ON_SEND

Instance Attribute Summary

Attributes inherited from Base

#config, #processed_source

Instance Method Summary collapse

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

#on_block(node) ⇒ Object 


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# File 'lib/rubocop/cop/lint/next_without_accumulator.rb', line 33

def on_block(node)
  on_body_of_reduce(node) do |body|
    void_next = body.each_node(:next).find do |n|
      n.children.empty? && parent_block_node(n) == node
    end

    add_offense(void_next) if void_next
  end
end

#on_body_of_reduce(node) ⇒ Object 


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# File 'lib/rubocop/cop/lint/next_without_accumulator.rb', line 29

def_node_matcher :on_body_of_reduce, <<~PATTERN
  (block (send _recv {:reduce :inject} !sym) _blockargs $(begin ...))
PATTERN