Class: RuboCop::Cop::InternalAffairs::SingleLineComparison

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

Overview

Enforces the use of ‘node.single_line?` instead of comparing `first_line` and `last_line` for equality.

Examples:

# bad
node.loc.first_line == node.loc.last_line

# bad
node.loc.last_line == node.loc.first_line

# bad
node.loc.line == node.loc.last_line

# bad
node.loc.last_line == node.loc.line

# bad
node.first_line == node.last_line

# good
node.single_line?

Constant Summary collapse

MSG =
'Use `%<preferred>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 inherited from Base

#active_support_extensions_enabled?, #add_global_offense, #add_offense, autocorrect_incompatible_with, badge, #begin_investigation, 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, #inspect, 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?, #autocorrect_with_disable_uncorrectable?, #correctable?, #disable_uncorrectable?, #safe_autocorrect?

Methods included from RuboCop::Cop::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



42
43
44
45
46
47
48
49
50
51
# File 'lib/rubocop/cop/internal_affairs/single_line_comparison.rb', line 42

def on_send(node)
  return unless (receiver = single_line_comparison(node))

  bang = node.method?(:!=) ? '!' : ''
  preferred = "#{bang}#{extract_receiver(receiver)}.single_line?"

  add_offense(node, message: format(MSG, preferred: preferred)) do |corrector|
    corrector.replace(node, preferred)
  end
end

#single_line_comparison(node) ⇒ Object



35
36
37
38
39
40
# File 'lib/rubocop/cop/internal_affairs/single_line_comparison.rb', line 35

def_node_matcher :single_line_comparison, <<~PATTERN
  {
    (send (send $_receiver {:line :first_line}) {:== :!=} (send _receiver :last_line))
    (send (send $_receiver :last_line) {:== :!=} (send _receiver {:line :first_line}))
  }
PATTERN