class RuboCop::Cop::Style::RedundantReturn

This cop checks for redundant `return` expressions.

@example

def test
  return something
end

def test
  one
  two
  three
  return something
end

It should be extended to handle methods whose body is if/else or a case expression with a default branch.

Constants

MSG
MULTI_RETURN_MSG

Public Instance Methods

on_def(node) click to toggle source
# File lib/rubocop/cop/style/redundant_return.rb, line 26
def on_def(node)
  return unless node.body

  check_branch(node.body)
end
Also aliased as: on_defs
on_defs(node)
Alias for: on_def

Private Instance Methods

add_braces(corrector, node) click to toggle source
# File lib/rubocop/cop/style/redundant_return.rb, line 59
def add_braces(corrector, node)
  kids = node.children.map(&:source_range)
  corrector.insert_before(kids.first, '{')
  corrector.insert_after(kids.last, '}')
end
add_brackets(corrector, node) click to toggle source
# File lib/rubocop/cop/style/redundant_return.rb, line 53
def add_brackets(corrector, node)
  kids = node.children.map(&:source_range)
  corrector.insert_before(kids.first, '[')
  corrector.insert_after(kids.last, ']')
end
allow_multiple_return_values?() click to toggle source
# File lib/rubocop/cop/style/redundant_return.rb, line 118
def allow_multiple_return_values?
  cop_config['AllowMultipleReturnValues'] || false
end
arguments?(args) click to toggle source
# File lib/rubocop/cop/style/redundant_return.rb, line 65
def arguments?(args)
  return false if args.empty?
  return true if args.size > 1

  !args.first.begin_type? || !args.first.children.empty?
end
autocorrect(node) click to toggle source
# File lib/rubocop/cop/style/redundant_return.rb, line 35
def autocorrect(node)
  lambda do |corrector|
    unless arguments?(node.children)
      corrector.replace(node.source_range, 'nil')
      next
    end

    return_value, = *node
    if node.children.size > 1
      add_brackets(corrector, node)
    elsif return_value.hash_type?
      add_braces(corrector, return_value) unless return_value.braces?
    end
    return_kw = range_with_surrounding_space(node.loc.keyword, :right)
    corrector.remove(return_kw)
  end
end
check_begin_node(node) click to toggle source
# File lib/rubocop/cop/style/redundant_return.rb, line 109
def check_begin_node(node)
  expressions = *node
  last_expr = expressions.last

  return unless last_expr && last_expr.return_type?

  check_return_node(last_expr)
end
check_branch(node) click to toggle source
# File lib/rubocop/cop/style/redundant_return.rb, line 72
def check_branch(node)
  case node.type
  when :return then check_return_node(node)
  when :case   then check_case_node(node)
  when :if     then check_if_node(node)
  when :begin  then check_begin_node(node)
  end
end
check_case_node(node) click to toggle source
# File lib/rubocop/cop/style/redundant_return.rb, line 88
def check_case_node(node)
  _cond, *when_nodes, else_node = *node
  when_nodes.each { |when_node| check_when_node(when_node) }
  check_branch(else_node) if else_node
end
check_if_node(node) click to toggle source
# File lib/rubocop/cop/style/redundant_return.rb, line 100
def check_if_node(node)
  return if node.modifier_form? || node.ternary?

  _cond, if_node, else_node = *node.node_parts

  check_branch(if_node) if if_node
  check_branch(else_node) if else_node
end
check_return_node(node) click to toggle source
# File lib/rubocop/cop/style/redundant_return.rb, line 81
def check_return_node(node)
  return if cop_config['AllowMultipleReturnValues'] &&
            node.children.size > 1

  add_offense(node, location: :keyword)
end
check_when_node(node) click to toggle source
# File lib/rubocop/cop/style/redundant_return.rb, line 94
def check_when_node(node)
  return unless node
  _cond, body = *node
  check_branch(body) if body
end
message(node) click to toggle source
# File lib/rubocop/cop/style/redundant_return.rb, line 122
def message(node)
  if !allow_multiple_return_values? && node.children.size > 1
    "#{MSG} #{MULTI_RETURN_MSG}"
  else
    MSG
  end
end