Class: RuboCop::Cop::Lint::SelfAssignment

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

Overview

This cop checks for self-assignments.

Examples:

# bad
foo = foo
foo, bar = foo, bar
Foo = Foo

# good
foo = bar
foo, bar = bar, foo
Foo = Bar

Constant Summary collapse

MSG =
'Self-assignment detected.'
ASSIGNMENT_TYPE_TO_RHS_TYPE =
{
  lvasgn: :lvar,
  ivasgn: :ivar,
  cvasgn: :cvar,
  gvasgn: :gvar
}.freeze

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_casgn(node) ⇒ Object


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

def on_casgn(node)
  lhs_scope, lhs_name, rhs = *node
  return unless rhs&.const_type?

  rhs_scope, rhs_name = *rhs
  add_offense(node) if lhs_scope == rhs_scope && lhs_name == rhs_name
end

#on_lvasgn(node) ⇒ Object Also known as: on_ivasgn, on_cvasgn, on_gvasgn


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

def on_lvasgn(node)
  lhs, rhs = *node
  return unless rhs

  rhs_type = ASSIGNMENT_TYPE_TO_RHS_TYPE[node.type]

  add_offense(node) if rhs.type == rhs_type && rhs.source == lhs.to_s
end

#on_masgn(node) ⇒ Object


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# File 'lib/rubocop/cop/lint/self_assignment.rb', line 49

def on_masgn(node)
  add_offense(node) if multiple_self_assignment?(node)
end

#on_or_asgn(node) ⇒ Object Also known as: on_and_asgn


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# File 'lib/rubocop/cop/lint/self_assignment.rb', line 53

def on_or_asgn(node)
  lhs, rhs = *node
  add_offense(node) if rhs_matches_lhs?(rhs, lhs)
end