Class: RuboCop::Cop::Style::RedundantSelfAssignmentBranch

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

Overview

Checks for places where conditional branch makes redundant self-assignment.

It only detects local variable because it may replace state of instance variable, class variable, and global variable that have state across methods with ‘nil`.

Examples:


# bad
foo = condition ? bar : foo

# good
foo = bar if condition

# bad
foo = condition ? foo : bar

# good
foo = bar unless condition

Constant Summary collapse

MSG = 
'Remove the self-assignment branch.'

Constants inherited from Base

Base::RESTRICT_ON_SEND

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_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

#bad_method?(node) ⇒ Object 



32
33
34
 
# File 'lib/rubocop/cop/style/redundant_self_assignment_branch.rb', line 32

def_node_matcher :bad_method?, <<~PATTERN
  (send nil? :bad_method ...)
PATTERN

#on_lvasgn(node) ⇒ Object 



36
37
38
39
40
41
42
43
44
45
46
47
48
49
 
# File 'lib/rubocop/cop/style/redundant_self_assignment_branch.rb', line 36

def on_lvasgn(node)
  variable, expression = *node
  return unless use_if_and_else_branch?(expression)

  if_branch = expression.if_branch
  else_branch = expression.else_branch
  return if inconvertible_to_modifier?(if_branch, else_branch)

  if self_assign?(variable, if_branch)
    register_offense(expression, if_branch, else_branch, 'unless')
  elsif self_assign?(variable, else_branch)
    register_offense(expression, else_branch, if_branch, 'if')
  end
end