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Class: RuboCop::AST::Node

Overview

Node is a subclass of Parser::AST::Node. It provides access to parent nodes and an object-oriented way to traverse an AST with the power of Enumerable.

It has predicate methods for every node type, like this:

Examples:

node.send_type?    # Equivalent to: `node.type == :send`
node.op_asgn_type? # Equivalent to: `node.type == :op_asgn`

# Non-word characters (other than a-zA-Z0-9_) in type names are omitted.
node.defined_type? # Equivalent to: `node.type == :defined?`

# Find the first lvar node under the receiver node.
lvar_node = node.each_descendant.find(&:lvar_type?)

Constant Summary

Class Method Summary

NodePattern::Macros - Extended

def_node_matcher

Define a method which applies a pattern to an AST node.

def_node_search

Define a method which recurses over the descendants of an AST node, checking whether any of them match the provided pattern.

Instance Attribute Summary

Instance Method Summary

Descendence - Included

#child_nodes

Returns an array of child nodes.

#descendants

Returns an array of descendant nodes.

#each_child_node

Calls the given block for each child node.

#each_descendant

Calls the given block for each descendant node with depth first order.

#each_node

Calls the given block for the receiver and each descendant node in depth-first order.

Sexp - Included

#s

Creates a Node with type type and children children.

Constructor Details

.new(type, children = EMPTY_CHILDREN, properties = EMPTY_PROPERTIES) ⇒ Node

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# File 'lib/rubocop/ast/node.rb', line 162

def initialize(type, children = EMPTY_CHILDREN, properties = EMPTY_PROPERTIES)
  @mutable_attributes = {}

  # ::AST::Node#initialize freezes itself.
  super

  # #parent= may be invoked multiple times for a node because there are
  # pending nodes while constructing AST and they are replaced later.
  # For example, `lvar` and `send` type nodes are initially created as an
  # `ident` type node and fixed to the appropriate type later.
  # So, the #parent attribute needs to be mutable.
  each_child_node do |child_node|
    child_node.parent = self unless child_node.complete?
  end
end

Class Method Details

.def_recursive_literal_predicate(kind) (private)

Define a recursive_? predicate method for the given node kind.

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# File 'lib/rubocop/ast/node.rb', line 141

private_class_method def self.def_recursive_literal_predicate(kind) # rubocop:disable Metrics/MethodLength
  recursive_kind = "recursive_#{kind}?"
  kind_filter = "#{kind}?"

  class_eval <<~RUBY, __FILE__, __LINE__ + 1
    def #{recursive_kind}                                     # def recursive_literal?
      case type                                               #   case type
      when :send                                              #   when :send
        LITERAL_RECURSIVE_METHODS.include?(method_name) &&    #     LITERAL_RECURSIVE_METHODS.include?(method_name) &&
          receiver.send(:#{recursive_kind}) &&                #       receiver.send(:recursive_literal?) &&
          arguments.all?(&:#{recursive_kind})                 #       arguments.all?(&:recursive_literal?)
      when LITERAL_RECURSIVE_TYPES                            #   when LITERAL_RECURSIVE_TYPES
        children.compact.all?(&:#{recursive_kind})            #     children.compact.all?(&:recursive_literal?)
      else                                                    #   else
        send(:#{kind_filter})                                 #     send(:literal?)
      end                                                     #   end
    end                                                       # end
  RUBY
end

Instance Attribute Details

#any_block_type?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 565

def any_block_type?
  GROUP_FOR_TYPE[type] == :any_block
end

#any_def_type?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 545

def any_def_type?
  GROUP_FOR_TYPE[type] == :any_def
end

#any_match_pattern_type?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 569

def any_match_pattern_type?
  GROUP_FOR_TYPE[type] == :any_match_pattern
end

#any_str_type?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 573

def any_str_type?
  GROUP_FOR_TYPE[type] == :any_str
end

#any_sym_type?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 577

def any_sym_type?
  GROUP_FOR_TYPE[type] == :any_sym
end

#argument?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 539

def argument?
  return false unless parent&.send_type?

  parent.arguments.any? { |argument| argument.equal?(self) }
end

#argument_type?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 549

def argument_type?
  GROUP_FOR_TYPE[type] == :argument
end

#assignment?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 491

def assignment?
  ASSIGNMENTS.include?(type)
end

#basic_conditional?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 495

def basic_conditional?
  BASIC_CONDITIONALS.include?(type)
end

#basic_literal?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 449

def basic_literal?
  BASIC_LITERALS.include?(type)
end

#begin_value_used?Boolean (readonly, private)

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# File 'lib/rubocop/ast/node.rb', line 727

def begin_value_used?
  # the last child node determines the value of the parent
  sibling_index == parent.children.size - 1 ? parent.value_used? : false
end

#boolean_type?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 553

def boolean_type?
  GROUP_FOR_TYPE[type] == :boolean
end

#call_type?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 531

def call_type?
  GROUP_FOR_TYPE[type] == :call
end

#case_if_value_used?Boolean (readonly, private)

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# File 'lib/rubocop/ast/node.rb', line 738

def case_if_value_used?
  # (case <condition> <when...>)
  # (if <condition> <truebranch> <falsebranch>)
  sibling_index.zero? || parent.value_used?
end

#chained?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 535

def chained?
  parent&.call_type? && equal?(parent.receiver)
end

#complete?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 236

def complete?
  @mutable_attributes.frozen?
end

#conditional?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 499

def conditional?
  CONDITIONALS.include?(type)
end

#empty_source?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 435

def empty_source?
  source_length.zero?
end

#equals_asgn?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 483

def equals_asgn?
  EQUALS_ASSIGNMENTS.include?(type)
end

#falsey_literal?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 457

def falsey_literal?
  FALSEY_LITERALS.include?(type)
end

#for_value_used?Boolean (readonly, private)

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# File 'lib/rubocop/ast/node.rb', line 732

def for_value_used?
  # `for var in enum; body; end`
  # (for <var> <enum> <body>)
  sibling_index == 2 ? parent.value_used? : true
end

#guard_clause?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 581

def guard_clause?
  node = operator_keyword? ? rhs : self

  node.match_guard_clause?
end

#immutable_literal?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 465

def immutable_literal?
  IMMUTABLE_LITERALS.include?(type)
end

#keyword?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 512

def keyword?
  return true if special_keyword? || (send_type? && prefix_not?)
  return false unless KEYWORDS.include?(type)

  !OPERATOR_KEYWORDS.include?(type) || loc.operator.is?(type.to_s)
end

#literal?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 445

def literal?
  LITERALS.include?(type)
end

#loop_keyword?Boolean (readonly)

Note
loop { } is a normal method call and thus not a loop keyword.
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# File 'lib/rubocop/ast/node.rb', line 508

def loop_keyword?
  LOOP_TYPES.include?(type)
end

#multiline?Boolean (readonly)

Predicates

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# File 'lib/rubocop/ast/node.rb', line 427

def multiline?
  line_count > 1
end

#mutable_literal?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 461

def mutable_literal?
  MUTABLE_LITERALS.include?(type)
end

#numeric_type?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 557

def numeric_type?
  GROUP_FOR_TYPE[type] == :numeric
end

#operator_keyword?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 523

def operator_keyword?
  OPERATOR_KEYWORDS.include?(type)
end

#parentNode? (rw)

Returns the parent node, or nil if the receiver is a root node.

Returns:

  • (Node, nil)

    the parent node or nil

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# File 'lib/rubocop/ast/node.rb', line 213

def parent
  @mutable_attributes[:parent]
end

#parent?Boolean (rw)

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# File 'lib/rubocop/ast/node.rb', line 222

def parent?
  !!parent
end

#parenthesized_call?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 527

def parenthesized_call?
  loc_is?(:begin, '(')
end

#post_condition_loop?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 503

def post_condition_loop?
  POST_CONDITION_LOOP_TYPES.include?(type)
end

#pure?Boolean (readonly)

Some expressions are evaluated for their value, some for their side effects, and some for both. If we know that expressions are useful only for their return values, and have no side effects, that means we can reorder them, change the number of times they are evaluated, or replace them with other expressions which are equivalent in value. So, is evaluation of this node free of side effects?

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# File 'lib/rubocop/ast/node.rb', line 693

def pure?
  # Be conservative and return false if we're not sure
  case type
  when :__FILE__, :__LINE__, :const, :cvar, :defined?, :false, :float,
       :gvar, :int, :ivar, :lvar, :nil, :str, :sym, :true, :regopt
    true
  when :and, :array, :begin, :case, :dstr, :dsym, :eflipflop, :ensure,
       :erange, :for, :hash, :if, :iflipflop, :irange, :kwbegin, :not,
       :or, :pair, :regexp, :until, :until_post, :when, :while,
       :while_post
    child_nodes.all?(&:pure?)
  else
    false
  end
end

#range_type?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 561

def range_type?
  GROUP_FOR_TYPE[type] == :range
end

#reference?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 479

def reference?
  REFERENCES.include?(type)
end

#root?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 227

def root?
  !parent
end

#send_type?Boolean (readonly)

Most nodes are of 'send' type, so this method is defined separately to make this check as fast as possible.

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# File 'lib/rubocop/ast/node.rb', line 206

def send_type?
  false
end

#shorthand_asgn?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 487

def shorthand_asgn?
  SHORTHAND_ASSIGNMENTS.include?(type)
end

#single_line?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 431

def single_line?
  line_count == 1
end

#special_keyword?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 519

def special_keyword?
  SPECIAL_KEYWORD_TYPES.include?(type) && SPECIAL_KEYWORDS.include?(source)
end

#truthy_literal?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 453

def truthy_literal?
  TRUTHY_LITERALS.include?(type)
end

#value_used?Boolean (readonly)

Some expressions are evaluated for their value, some for their side effects, and some for both If we know that an expression is useful only for its side effects, that means we can transform it in ways which preserve the side effects, but change the return value So, does the return value of this node matter? If we changed it to (…​; nil), might that affect anything?

[ GitHub ]

  
# File 'lib/rubocop/ast/node.rb', line 663

def value_used? # rubocop:disable Metrics/MethodLength
  # Be conservative and return true if we're not sure.
  return false if parent.nil?

  case parent.type
  when :array, :defined?, :dstr, :dsym, :eflipflop, :erange, :float,
       :hash, :iflipflop, :irange, :not, :pair, :regexp, :str, :sym,
       :when, :xstr
    parent.value_used?
  when :begin, :kwbegin
    begin_value_used?
  when :for
    for_value_used?
  when :case, :if
    case_if_value_used?
  when :while, :until, :while_post, :until_post
    while_until_value_used?
  else
    true
  end
end

#variable?Boolean (readonly)

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# File 'lib/rubocop/ast/node.rb', line 475

def variable?
  VARIABLES.include?(type)
end

#while_until_value_used?Boolean (readonly, private)

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# File 'lib/rubocop/ast/node.rb', line 744

def while_until_value_used?
  # (while <condition> <body>) -> always evaluates to `nil`
  sibling_index.zero?
end

Instance Method Details

#ancestorsArray<Node>

Returns an array of ancestor nodes. This is a shorthand for node.each_ancestor.to_a.

Returns:

  • (Array<Node>)

    an array of ancestor nodes

[ GitHub ]

  
# File 'lib/rubocop/ast/node.rb', line 334

def ancestors
  each_ancestor.to_a
end

#assignment_or_similar?(node = self)

Some cops treat the shovel operator as a kind of assignment.

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# File 'lib/rubocop/ast/node.rb', line 441

def_node_matcher :assignment_or_similar?, <<~PATTERN
  {assignment? (send _recv :<< ...)}
PATTERN

#class_constructor?(node = self)

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# File 'lib/rubocop/ast/node.rb', line 625

def_node_matcher :class_constructor?, <<~PATTERN
  {
    (send #global_const?({:Class :Module :Struct}) :new ...)
    (send #global_const?(:Data) :define ...)
    (any_block {
      (send #global_const?({:Class :Module :Struct}) :new ...)
      (send #global_const?(:Data) :define ...)
    } ...)
  }
PATTERN

#class_definition?(node = self)

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# File 'lib/rubocop/ast/node.rb', line 643

def_node_matcher :class_definition?, <<~PATTERN
  {(class _ _ $_)
   (sclass _ $_)
   (any_block (send #global_const?({:Struct :Class}) :new ...) _ $_)}
PATTERN

#complete!

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# File 'lib/rubocop/ast/node.rb', line 231

def complete!
  @mutable_attributes.freeze
  each_child_node(&:complete!)
end

#const_name

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# File 'lib/rubocop/ast/node.rb', line 380

def const_name
  return unless const_type? || casgn_type?

  if namespace && !namespace.cbase_type?
    "#{namespace.const_name}::#{short_name}"
  else
    short_name.to_s
  end
end

#defined_module

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# File 'lib/rubocop/ast/node.rb', line 400

def defined_module
  namespace, name = *defined_module0
  s(:const, namespace, name) if name
end

#defined_module0(node = self) (private)

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# File 'lib/rubocop/ast/node.rb', line 391

def_node_matcher :defined_module0, <<~PATTERN
  {(class (const $_ $_) ...)
   (module (const $_ $_) ...)
   (casgn $_ $_        (send #global_const?({:Class :Module}) :new ...))
   (casgn $_ $_ (block (send #global_const?({:Class :Module}) :new ...) ...))}
PATTERN

#defined_module_name

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# File 'lib/rubocop/ast/node.rb', line 405

def defined_module_name
  (const = defined_module) && const.const_name
end

#each_ancestorself, Enumerator #each_ancestor(type) ⇒ self, Enumerator #each_ancestor(type_a, type_b, ...) ⇒ self, Enumerator

Calls the given block for each ancestor node from parent to root. If no block is given, an Enumerator is returned.

Overloads:

  • #each_ancestorself, Enumerator

    Yield all nodes.

  • #each_ancestor(type) ⇒ self, Enumerator

    Yield only nodes matching the type.

    Parameters:

    • type (Symbol)

      a node type

  • #each_ancestor(type_a, type_b, ...) ⇒ self, Enumerator

    Yield only nodes matching any of the types.

    Parameters:

    • type_a (Symbol)

      a node type

    • type_b (Symbol)

      a node type

Yield Parameters:

  • node (Node)

    each ancestor node

Returns:

  • (self)

    if a block is given

  • (Enumerator)

    if no block is given

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# File 'lib/rubocop/ast/node.rb', line 322

def each_ancestor(*types, &block)
  return to_enum(__method__, *types) unless block

  visit_ancestors(types, &block)

  self
end

#first_line

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# File 'lib/rubocop/ast/node.rb', line 348

def first_line
  loc.line
end

#global_const?(node = self, name)

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# File 'lib/rubocop/ast/node.rb', line 622

def_node_matcher :global_const?, '(const {nil? cbase} %1)'

#lambda?(node = self)

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# File 'lib/rubocop/ast/node.rb', line 616

def_node_matcher :lambda?, '(any_block (send nil? :lambda) ...)'

#lambda_or_proc?(node = self)

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# File 'lib/rubocop/ast/node.rb', line 619

def_node_matcher :lambda_or_proc?, '{lambda? proc?}'

#last_line

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# File 'lib/rubocop/ast/node.rb', line 352

def last_line
  loc.last_line
end

#left_siblingNode?

Use is discouraged, this is a potentially slow method and can lead to even slower algorithms

Returns:

  • (Node, nil)

    the left (aka previous) sibling

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# File 'lib/rubocop/ast/node.rb', line 274

def left_sibling
  i = sibling_index
  return if i.nil? || i.zero?

  parent.children[i - 1].freeze
end

#left_siblingsArray<Node>

Use is discouraged, this is a potentially slow method and can lead to even slower algorithms

Returns:

  • (Array<Node>)

    the left (aka previous) siblings

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# File 'lib/rubocop/ast/node.rb', line 284

def left_siblings
  return [].freeze unless parent

  parent.children[0...sibling_index].freeze
end

#line_count

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# File 'lib/rubocop/ast/node.rb', line 356

def line_count
  return 0 unless source_range

  source_range.last_line - source_range.first_line + 1
end

#loc?(which_loc) ⇒ Boolean

Shortcut to safely check if a location is present

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# File 'lib/rubocop/ast/node.rb', line 589

def loc?(which_loc)
  return false unless loc.respond_to?(which_loc)

  !loc.public_send(which_loc).nil?
end

#loc_is?(which_loc, str) ⇒ Boolean

Shortcut to safely test a particular location, even if this location does not exist or is nil

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# File 'lib/rubocop/ast/node.rb', line 597

def loc_is?(which_loc, str)
  return false unless loc?(which_loc)

  loc.public_send(which_loc).is?(str)
end

#match_guard_clause?(node = self)

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# File 'lib/rubocop/ast/node.rb', line 604

def_node_matcher :match_guard_clause?, <<~PATTERN
  [${(send nil? {:raise :fail} ...) return break next} single_line?]
PATTERN

#module_definition?(node = self)

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# File 'lib/rubocop/ast/node.rb', line 650

def_node_matcher :module_definition?, <<~PATTERN
  {(module _ $_)
   (any_block (send #global_const?(:Module) :new ...) _ $_)}
PATTERN

#new_class_or_module_block?(node = self) (private)

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# File 'lib/rubocop/ast/node.rb', line 788

def_node_matcher :new_class_or_module_block?, <<~PATTERN
  ^(casgn _ _ (block (send (const _ {:Class :Module}) :new) ...))
PATTERN

#node_partsArray<Node>

Common destructuring method. This can be used to normalize destructuring for different variations of the node. Some node types override this with their own custom destructuring method.

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# File 'lib/rubocop/ast/node.rb', line 305

alias node_parts to_a

#nonempty_line_count

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# File 'lib/rubocop/ast/node.rb', line 362

def nonempty_line_count
  source.lines.grep(/\S/).size
end

#parent_module_name

Searching the AST

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# File 'lib/rubocop/ast/node.rb', line 411

def parent_module_name
  # what class or module is this method/constant/etc definition in?
  # returns nil if answer cannot be determined
  ancestors = each_ancestor(:class, :module, :sclass, :casgn, :block)
  result    = ancestors.filter_map do |ancestor|
    parent_module_name_part(ancestor) do |full_name|
      return nil unless full_name

      full_name
    end
  end.reverse.join('::')
  result.empty? ? 'Object' : result
end

#parent_module_name_for_block(ancestor) (private)

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# File 'lib/rubocop/ast/node.rb', line 774

def parent_module_name_for_block(ancestor)
  if ancestor.method?(:class_eval)
    # `class_eval` with no receiver applies to whatever module or class
    # we are currently in
    return unless (receiver = ancestor.receiver)

    yield unless receiver.const_type?
    receiver.const_name
  elsif !new_class_or_module_block?(ancestor)
    yield
  end
end

#parent_module_name_for_sclass(sclass_node) (private)

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# File 'lib/rubocop/ast/node.rb', line 762

def parent_module_name_for_sclass(sclass_node)
  # TODO: look for constant definition and see if it is nested
  # inside a class or module
  subject = sclass_node.children[0]

  if subject.const_type?
    "#<Class:#{subject.const_name}>"
  elsif subject.self_type?
    "#<Class:#{sclass_node.parent_module_name}>"
  end
end

#parent_module_name_part(node) (private)

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# File 'lib/rubocop/ast/node.rb', line 749

def parent_module_name_part(node)
  case node.type
  when :class, :module, :casgn
    # TODO: if constant name has cbase (leading ::), then we don't need
    # to keep traversing up through nested classes/modules
    node.defined_module_name
  when :sclass
    yield parent_module_name_for_sclass(node)
  else # block
    parent_module_name_for_block(node) { yield nil }
  end
end

#proc?(node = self)

[ GitHub ]

  
# File 'lib/rubocop/ast/node.rb', line 609

def_node_matcher :proc?, <<~PATTERN
  {(block (send nil? :proc) ...)
   (block (send #global_const?(:Proc) :new) ...)
   (send #global_const?(:Proc) :new)}
PATTERN

#receiver(node = self)

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# File 'lib/rubocop/ast/node.rb', line 373

def_node_matcher :receiver, <<~PATTERN
  {(send $_ ...) (any_block (call $_ ...) ...)}
PATTERN

#recursive_basic_literal?Boolean

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# File 'lib/rubocop/ast/node.rb', line 473

def_recursive_literal_predicate :basic_literal

#recursive_literal?Boolean

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# File 'lib/rubocop/ast/node.rb', line 472

def_recursive_literal_predicate :literal

#right_siblingNode?

Use is discouraged, this is a potentially slow method and can lead to even slower algorithms

Returns:

  • (Node, nil)

    the right (aka next) sibling

[ GitHub ]

  
# File 'lib/rubocop/ast/node.rb', line 265

def right_sibling
  return unless parent

  parent.children[sibling_index + 1].freeze
end

#right_siblingsArray<Node>

Use is discouraged, this is a potentially slow method and can lead to even slower algorithms

Returns:

  • (Array<Node>)

    the right (aka next) siblings

[ GitHub ]

  
# File 'lib/rubocop/ast/node.rb', line 293

def right_siblings
  return [].freeze unless parent

  parent.children[(sibling_index + 1)..].freeze
end

#sibling_indexInteger?

Returns the index of the receiver node in its siblings. (Sibling index uses zero based numbering.) Use is discouraged, this is a potentially slow method.

Returns:

  • (Integer, nil)

    the index of the receiver node in its siblings

[ GitHub ]

  
# File 'lib/rubocop/ast/node.rb', line 258

def sibling_index
  parent&.children&.index { |sibling| sibling.equal?(self) }
end

#sourceString?

Note
Some rare nodes may have no source, like s(:args) in foo {}
[ GitHub ]

  
# File 'lib/rubocop/ast/node.rb', line 340

def source
  loc.expression&.source
end

#source_length

[ GitHub ]

  
# File 'lib/rubocop/ast/node.rb', line 366

def source_length
  source_range ? source_range.size : 0
end

#source_range

[ GitHub ]

  
# File 'lib/rubocop/ast/node.rb', line 344

def source_range
  loc.expression
end

#str_content(node = self)

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# File 'lib/rubocop/ast/node.rb', line 378

def_node_matcher :str_content, '(str $_)'

#struct_constructor?(node = self)

Deprecated.

Use :class_constructor?

[ GitHub ]

  
# File 'lib/rubocop/ast/node.rb', line 638

def_node_matcher :struct_constructor?, <<~PATTERN
  (any_block (send #global_const?(:Struct) :new ...) _ $_)
PATTERN

#type?(*types) ⇒ Boolean

Determine if the node is one of several node types in a single query Allows specific single node types, as well as "grouped" types (e.g. :boolean for :true or :false)

[ GitHub ]

  
# File 'lib/rubocop/ast/node.rb', line 181

def type?(*types)
  type_in?(types)
end

#type_in?(types) ⇒ Boolean

Non-splatting variant of #type?, used by the traversal hot paths to avoid allocating an array per visited node.

[ GitHub ]

  
# File 'lib/rubocop/ast/node.rb', line 188

def type_in?(types)
  return true if types.include?(type)

  group_type = GROUP_FOR_TYPE[type]
  !group_type.nil? && types.include?(group_type)
end

#updated(type = nil, children = nil, properties = {})

Override #updated so that AST::Processor does not try to mutate our ASTs. Since we keep references from children to parents and not just the other way around, we cannot update an AST and share identical subtrees. Rather, the entire AST must be copied any time any part of it is changed.

[ GitHub ]

  
# File 'lib/rubocop/ast/node.rb', line 247

def updated(type = nil, children = nil, properties = {})
  properties[:location] ||= @location
  klass = RuboCop::AST::Builder::NODE_MAP[type || @type] || Node
  klass.new(type || @type, children || @children, properties)
end

#visit_ancestors(types) (private)

[ GitHub ]

  
# File 'lib/rubocop/ast/node.rb', line 711

def visit_ancestors(types)
  last_node = self

  if types.empty?
    while (current_node = last_node.parent)
      yield current_node
      last_node = current_node
    end
  else
    while (current_node = last_node.parent)
      yield current_node if current_node.type_in?(types)
      last_node = current_node
    end
  end
end