Class: RuboCop::Cop::Style::UnlessLogicalOperators

Inherits:
Base
  • Object
show all
Includes:
ConfigurableEnforcedStyle
Defined in:
lib/rubocop/cop/style/unless_logical_operators.rb

Overview

Checks for the use of logical operators in an unless condition. It discourages such code, as the condition becomes more difficult to read and understand.

This cop supports two styles:

  • forbid_mixed_logical_operators (default)

  • forbid_logical_operators

forbid_mixed_logical_operators style forbids the use of more than one type of logical operators. This makes the unless condition easier to read because either all conditions need to be met or any condition need to be met in order for the expression to be truthy or falsey.

forbid_logical_operators style forbids any use of logical operator. This makes it even more easy to read the unless condition as there is only one condition in the expression.

Examples:

EnforcedStyle: forbid_mixed_logical_operators (default)

# bad
return unless a || b && c
return unless a && b || c
return unless a && b and c
return unless a || b or c
return unless a && b or c
return unless a || b and c

# good
return unless a && b && c
return unless a || b || c
return unless a and b and c
return unless a or b or c
return unless a?

EnforcedStyle: forbid_logical_operators

# bad
return unless a || b
return unless a && b
return unless a or b
return unless a and b

# good
return unless a
return unless a?

Constant Summary collapse

FORBID_MIXED_LOGICAL_OPERATORS = 
'Do not use mixed logical operators in an `unless`.'
FORBID_LOGICAL_OPERATORS = 
'Do not use any logical operator in an `unless`.'

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 ConfigurableEnforcedStyle

#alternative_style, #alternative_styles, #ambiguous_style_detected, #correct_style_detected, #detected_style, #detected_style=, #no_acceptable_style!, #no_acceptable_style?, #opposite_style_detected, #style, #style_configured?, #style_detected, #style_parameter_name, #supported_styles, #unexpected_style_detected

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 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

#and_with_or?(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/unless_logical_operators.rb', line 62

def_node_matcher :and_with_or?, <<~PATTERN
  (if (and <`or ...> ) ...)
PATTERN

#logical_operator?(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/unless_logical_operators.rb', line 67

def_node_matcher :logical_operator?, <<~PATTERN
  (if ({and or} ... ) ...)
PATTERN

#on_if(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/unless_logical_operators.rb', line 71

def on_if(node)
  return unless node.unless?

  if style == :forbid_mixed_logical_operators && mixed_logical_operator?(node)
    add_offense(node, message: FORBID_MIXED_LOGICAL_OPERATORS)
  elsif style == :forbid_logical_operators && logical_operator?(node)
    add_offense(node, message: FORBID_LOGICAL_OPERATORS)
  end
end

#or_with_and?(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/unless_logical_operators.rb', line 57

def_node_matcher :or_with_and?, <<~PATTERN
  (if (or <`and ...> ) ...)
PATTERN