Class: RuboCop::Cop::Lint::LiteralAsCondition

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

Overview

Checks for literals used as the conditions or as operands in and/or expressions serving as the conditions of if/while/until/case-when/case-in.

NOTE: Literals in ‘case-in` condition where the match variable is used in `in` are accepted as a pattern matching.

Examples:


# bad
if 20
  do_something
end

# bad
if some_var && true
  do_something
end

# good
if some_var && some_condition
  do_something
end

# good
# When using a boolean value for an infinite loop.
while true
  break if condition
end

Constant Summary collapse

MSG = 
'Literal `%<literal>s` appeared as a condition.'
RESTRICT_ON_SEND = 
[:!].freeze

Instance Attribute Summary

Attributes inherited from Base

#config, #processed_source

Instance Method Summary collapse

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

#message(node) ⇒ Object 



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# File 'lib/rubocop/cop/lint/literal_as_condition.rb', line 94

def message(node)
  format(MSG, literal: node.source)
end

#on_case(case_node) ⇒ Object 



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# File 'lib/rubocop/cop/lint/literal_as_condition.rb', line 59

def on_case(case_node)
  if case_node.condition
    check_case(case_node)
  else
    case_node.when_branches.each do |when_node|
      next unless when_node.conditions.all?(&:literal?)

      range = when_conditions_range(when_node)
      message = message(range)

      add_offense(range, message: message)
    end
  end
end

#on_case_match(case_match_node) ⇒ Object 



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# File 'lib/rubocop/cop/lint/literal_as_condition.rb', line 74

def on_case_match(case_match_node)
  if case_match_node.condition
    return if case_match_node.descendants.any?(&:match_var_type?)

    check_case(case_match_node)
  else
    case_match_node.each_in_pattern do |in_pattern_node|
      next unless in_pattern_node.condition.literal?

      add_offense(in_pattern_node)
    end
  end
end

#on_if(node) ⇒ Object 



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

def on_if(node)
  check_for_literal(node)
end

#on_send(node) ⇒ Object 



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# File 'lib/rubocop/cop/lint/literal_as_condition.rb', line 88

def on_send(node)
  return unless node.negation_method?

  check_for_literal(node)
end

#on_until(node) ⇒ Object Also known as: on_until_post 



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# File 'lib/rubocop/cop/lint/literal_as_condition.rb', line 52

def on_until(node)
  return if condition(node).false_type?

  check_for_literal(node)
end

#on_while(node) ⇒ Object Also known as: on_while_post 



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# File 'lib/rubocop/cop/lint/literal_as_condition.rb', line 45

def on_while(node)
  return if condition(node).true_type?

  check_for_literal(node)
end