class RuboCop::Cop::Style::ConstantVisibility

This cop checks that constants defined in classes and modules have an explicit visibility declaration. By default, Ruby makes all class- and module constants public, which litters the public API of the class or module. Explicitly declaring a visibility makes intent more clear, and prevents outside actors from touching private state.

@example

# bad
class Foo
  BAR = 42
  BAZ = 43
end

# good
class Foo
  BAR = 42
  private_constant :BAR

  BAZ = 43
  public_constant :BAZ
end

Constants

MSG

Public Instance Methods

on_casgn(node) click to toggle source
# File lib/rubocop/cop/style/constant_visibility.rb, line 33
def on_casgn(node)
  return unless class_or_module_scope?(node)
  return if visibility_declaration?(node)

  add_offense(node)
end

Private Instance Methods

class_or_module_scope?(node) click to toggle source
# File lib/rubocop/cop/style/constant_visibility.rb, line 48
def class_or_module_scope?(node)
  node.parent && %i[class module].include?(node.parent.type)
end
message(node) click to toggle source
# File lib/rubocop/cop/style/constant_visibility.rb, line 42
def message(node)
  _namespace, constant_name, _value = *node

  format(MSG, constant_name: constant_name)
end
visibility_declaration?(node) click to toggle source
# File lib/rubocop/cop/style/constant_visibility.rb, line 52
def visibility_declaration?(node)
  _namespace, constant_name, _value = *node

  node.parent.each_child_node(:send).any? do |child|
    visibility_declaration_for?(child, constant_name)
  end
end