Class: RuboCop::Cop::Lint::RequireParentheses

Inherits:
Cop
  • Object
show all
Includes:
IfNode
Defined in:
lib/rubocop/cop/lint/require_parentheses.rb

Overview

This cop checks for expressions where there is a call to a predicate method with at least one argument, where no parentheses are used around the parameter list, and a boolean operator, && or ||, is used in the last argument.

The idea behind warning for these constructs is that the user might be under the impression that the return value from the method call is an operand of &&/||.

Examples:


if day.is? :tuesday && month == :jan
  ...
end

Constant Summary collapse

MSG =
'Use parentheses in the method call to avoid confusion about ' \
'precedence.'

Constants included from Util

Util::ASGN_NODES, Util::EQUALS_ASGN_NODES, Util::OPERATOR_METHODS, Util::PROC_NEW_NODE, Util::SHORTHAND_ASGN_NODES

Instance Attribute Summary

Attributes inherited from Cop

#config, #corrections, #offenses, #processed_source

Instance Method Summary collapse

Methods included from IfNode

#elsif?, #if_else?, #modifier_if?, #ternary_op?

Methods inherited from Cop

#add_offense, all, #autocorrect?, #config_to_allow_offenses, #config_to_allow_offenses=, #cop_config, #cop_name, cop_name, cop_name_with_namespace, cop_type, #debug?, #display_cop_names?, inherited, #initialize, #join_force?, lint?, #message, non_rails, qualified_cop_name, rails?, #relevant_file?, #support_autocorrect?

Methods included from IgnoredNode

#ignore_node, #ignored_node?, #part_of_ignored_node?

Methods included from Util

begins_its_line?, block_length, command?, comment_line?, const_name, first_part_of_call_chain, lambda?, lambda_or_proc?, line_range, numeric_range_size, on_node, operator?, parentheses?, proc?, range_with_surrounding_comma, range_with_surrounding_space, source_range, strip_quotes, within_node?

Methods included from PathUtil

issue_deprecation_warning, match_path?, relative_path

Constructor Details

This class inherits a constructor from RuboCop::Cop::Cop

Instance Method Details

#on_send(node) ⇒ Object



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# File 'lib/rubocop/cop/lint/require_parentheses.rb', line 26

def on_send(node)
  _receiver, method_name, *args = *node

  return if parentheses?(node)
  return if args.empty?

  if ternary_op?(args.first)
    check_ternary(args.first, node)
  else
    # We're only checking predicate methods. There would be false
    # positives otherwise.
    check_send(args.last, node) if predicate?(method_name)
  end
end