Module: RuboCop::AST::Traversal

Included in:
Cop::Commissioner
Defined in:
lib/rubocop/ast/traversal.rb

Overview

Provides methods for traversing an AST. Does not transform an AST; for that, use Parser::AST::Processor. Override methods to perform custom processing. Remember to call ‘super` if you want to recursively process descendant nodes.

Constant Summary collapse

NO_CHILD_NODES = 
[:true, :false, :nil, :int, :float, :complex,
:rational, :str, :sym, :regopt, :self, :lvar,
:ivar, :cvar, :gvar, :nth_ref, :back_ref, :cbase,
:arg, :restarg, :blockarg, :shadowarg,
:kwrestarg, :zsuper, :lambda, :redo, :retry].freeze
ONE_CHILD_NODE = 
[:splat, :kwsplat, :block_pass, :not, :break, :next,
:preexe, :postexe, :match_current_line, :defined?,
:arg_expr].freeze
MANY_CHILD_NODES = 
[:dstr, :dsym, :xstr, :regexp, :array, :hash, :pair,
:irange, :erange, :mlhs, :masgn, :or_asgn, :and_asgn,
:undef, :alias, :args, :super, :yield, :or, :and,
:while_post, :until_post, :iflipflop, :eflipflop,
:match_with_lvasgn, :begin, :kwbegin, :return].freeze
SECOND_CHILD_ONLY = 
[:lvasgn, :ivasgn, :cvasgn, :gvasgn, :optarg, :kwarg,
:kwoptarg].freeze

Instance Method Summary collapse

Instance Method Details

#on_block(node) ⇒ Object 



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# File 'lib/rubocop/ast/traversal.rb', line 148

def on_block(node)
  children = node.children
  child = children[0]
  send(:"on_#{child.type}", child) # can be send, zsuper...
  on_args(children[1])
  return unless (child = children[2])
  send(:"on_#{child.type}", child)
end

#on_case(node) ⇒ Object Also known as: on_rescue, on_resbody, on_ensure, on_for, on_when 



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# File 'lib/rubocop/ast/traversal.rb', line 157

def on_case(node)
  node.children.each do |child|
    send(:"on_#{child.type}", child) if child
  end
  nil
end

#on_casgn(node) ⇒ Object 



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# File 'lib/rubocop/ast/traversal.rb', line 71

def on_casgn(node)
  children = node.children
  if (child = children[0]) # always const???
    send(:"on_#{child.type}", child)
  end
  return unless (child = children[2])
  send(:"on_#{child.type}", child)
end

#on_class(node) ⇒ Object 



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# File 'lib/rubocop/ast/traversal.rb', line 80

def on_class(node)
  children = node.children
  child = children[0] # always const???
  send(:"on_#{child.type}", child)
  if (child = children[1])
    send(:"on_#{child.type}", child)
  end
  return unless (child = children[2])
  send(:"on_#{child.type}", child)
end

#on_const(node) ⇒ Object 



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# File 'lib/rubocop/ast/traversal.rb', line 66

def on_const(node)
  return unless (child = node.children[0])
  send(:"on_#{child.type}", child)
end

#on_def(node) ⇒ Object 



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# File 'lib/rubocop/ast/traversal.rb', line 91

def on_def(node)
  children = node.children
  on_args(children[1])
  return unless (child = children[2])
  send(:"on_#{child.type}", child)
end

#on_defs(node) ⇒ Object 



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# File 'lib/rubocop/ast/traversal.rb', line 116

def on_defs(node)
  children = node.children
  child = children[0]
  send(:"on_#{child.type}", child)
  on_args(children[2])
  return unless (child = children[3])
  send(:"on_#{child.type}", child)
end

#on_if(node) ⇒ Object 



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# File 'lib/rubocop/ast/traversal.rb', line 125

def on_if(node)
  children = node.children
  child = children[0]
  send(:"on_#{child.type}", child)
  if (child = children[1])
    send(:"on_#{child.type}", child)
  end
  return unless (child = children[2])
  send(:"on_#{child.type}", child)
end

#on_op_asgn(node) ⇒ Object 



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# File 'lib/rubocop/ast/traversal.rb', line 108

def on_op_asgn(node)
  children = node.children
  child = children[0]
  send(:"on_#{child.type}", child)
  child = children[2]
  send(:"on_#{child.type}", child)
end

#on_send(node) ⇒ Object Also known as: on_csend 



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# File 'lib/rubocop/ast/traversal.rb', line 98

def on_send(node)
  node.children.each_with_index do |child, i|
    next if i == 1
    send(:"on_#{child.type}", child) if child
  end
  nil
end

#on_while(node) ⇒ Object Also known as: on_until, on_module, on_sclass 



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# File 'lib/rubocop/ast/traversal.rb', line 136

def on_while(node)
  children = node.children
  child = children[0]
  send(:"on_#{child.type}", child)
  return unless (child = children[1])
  send(:"on_#{child.type}", child)
end

#walk(node) ⇒ Object 



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# File 'lib/rubocop/ast/traversal.rb', line 10

def walk(node)
  return if node.nil?
  send(:"on_#{node.type}", node)
  nil
end