Class: RuboCop::Cop::Style::SlicingWithRange

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

Overview

Checks that arrays are not sliced with the redundant ‘ary`, replacing it with `ary`, and ensures arrays are sliced with endless ranges instead of `ary` on Ruby 2.6+, and with beginless ranges instead of `ary` on Ruby 2.7+.

Examples:

# bad
items[0..-1]
items[0..nil]
items[0...nil]

# good
items

# bad
items[1..-1]   # Ruby 2.6+
items[1..nil]  # Ruby 2.6+

# good
items[1..]     # Ruby 2.6+

# bad
items[nil..42] # Ruby 2.7+

# good
items[..42]    # Ruby 2.7+
items[0..42]   # Ruby 2.7+

Constant Summary collapse

MSG = 
'Prefer `%<prefer>s` over `%<current>s`.'
MSG_USELESS_RANGE = 
'Remove the useless `%<prefer>s`.'
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 included from TargetRubyVersion

minimum_target_ruby_version, required_minimum_ruby_version, support_target_ruby_version?

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_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

#on_send(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/slicing_with_range.rb', line 77

def on_send(node)
  return unless node.arguments.one?

  range_node = node.first_argument
  selector = node.loc.selector
  unless (message, removal_range = offense_message_with_removal_range(range_node, selector))
    return
  end

  add_offense(selector, message: message) do |corrector|
    corrector.remove(removal_range)
  end
end

#range_from_zero?(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/slicing_with_range.rb', line 73

def_node_matcher :range_from_zero?, <<~PATTERN
  (irange nil !nil?)
PATTERN

#range_from_zero_till_minus_one?(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/slicing_with_range.rb', line 57

def_node_matcher :range_from_zero_till_minus_one?, <<~PATTERN
  {
    (irange (int 0) {(int -1) nil})
    (erange (int 0) nil)
  }
PATTERN

#range_till_minus_one?(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/slicing_with_range.rb', line 65

def_node_matcher :range_till_minus_one?, <<~PATTERN
  {
    (irange !nil? {(int -1) nil})
    (erange !nil? nil)
  }
PATTERN