Class: RuboCop::Cop::Lint::AssignmentInCondition

Inherits:
Base
  • Object
show all
Extended by:
AutoCorrector
Includes:
SafeAssignment
Defined in:
lib/rubocop/cop/lint/assignment_in_condition.rb

Overview

Checks for assignments in the conditions of if/while/until.

‘AllowSafeAssignment` option for safe assignment. By safe assignment we mean putting parentheses around an assignment to indicate “I know I’m using an assignment as a condition. It’s not a mistake.”

Examples:

# bad
if some_var = value
  do_something
end

# good
if some_var == value
  do_something
end

AllowSafeAssignment: true (default)

# good
if (some_var = value)
  do_something
end

AllowSafeAssignment: false

# bad
if (some_var = value)
  do_something
end

Constant Summary collapse

MSG_WITH_SAFE_ASSIGNMENT_ALLOWED = 
'Use `==` if you meant to do a comparison or wrap the expression ' \
'in parentheses to indicate you meant to assign in a ' \
'condition.'
MSG_WITHOUT_SAFE_ASSIGNMENT_ALLOWED = 
'Use `==` if you meant to do a comparison or move the assignment ' \
'up out of the condition.'
ASGN_TYPES = 
[:begin, *AST::Node::EQUALS_ASSIGNMENTS, :send, :csend].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

#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?, #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_if(node) ⇒ Object Also known as: on_while, on_until 



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# File 'lib/rubocop/cop/lint/assignment_in_condition.rb', line 55

def on_if(node)
  return if node.condition.block_type?

  traverse_node(node.condition) do |asgn_node|
    next :skip_children if skip_children?(asgn_node)
    next if allowed_construct?(asgn_node)

    add_offense(asgn_node.loc.operator) do |corrector|
      next unless safe_assignment_allowed?

      corrector.wrap(asgn_node, '(', ')')
    end
  end
end