Class: RuboCop::Cop::Style::SwapValues

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

Overview

This cop enforces the use of shorthand-style swapping of 2 variables. Its autocorrection is marked as unsafe, because it can erroneously remove the temporary variable which is used later.

Examples:

# bad
tmp = x
x = y
y = tmp

# good
x, y = y, x

Constant Summary collapse

MSG =
'Replace this and assignments at lines %<x_line>d '\
'and %<y_line>d with `%<replacement>s`.'
SIMPLE_ASSIGNMENT_TYPES =
%i[lvasgn ivasgn cvasgn gvasgn casgn].to_set.freeze

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

#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?, #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_asgn(node) ⇒ Object


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# File 'lib/rubocop/cop/style/swap_values.rb', line 28

def on_asgn(node)
  return if allowed_assignment?(node)

  tmp_assign = node
  x_assign, y_assign = *node.right_siblings.take(2)
  return unless x_assign && y_assign && swapping_values?(tmp_assign, x_assign, y_assign)

  add_offense(node, message: message(x_assign, y_assign)) do |corrector|
    range = correction_range(tmp_assign, y_assign)
    corrector.replace(range, replacement(x_assign))
  end
end