Class: RuboCop::Cop::Discourse::Services::MutableAttributeDefault

Inherits:
Base
  • Object
show all
Extended by:
AutoCorrector
Defined in:
lib/rubocop/cop/discourse/services/mutable_attribute_default.rb

Overview

Wrap mutable ‘attribute` defaults in a proc — `ActiveModel::Attributes` shares the literal across instances, so mutations leak between calls. `:array`-typed attributes are exempt; the type dups on read.

Examples:

# bad
options do
attribute :overrides, default: {}
  attribute :ids, default: [1, 2]
end

# good
options do
attribute :overrides, default: -> { {} }
  attribute :ids, default: -> { [1, 2] }
  attribute :tags, :array, default: [] # :array dups per read
end

Constant Summary collapse

MSG = 
"Mutable `default: %<source>s` is shared across all instances; wrap it in a proc: `-> { %<source>s }`."
RESTRICT_ON_SEND = 
%i[attribute].freeze

Instance Method Summary collapse

Instance Method Details

#on_class(node) ⇒ Object 



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# File 'lib/rubocop/cop/discourse/services/mutable_attribute_default.rb', line 49

def on_class(node)
  @service = true if service_include?(node)
end

#on_send(node) ⇒ Object 



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# File 'lib/rubocop/cop/discourse/services/mutable_attribute_default.rb', line 53

def on_send(node)
  return unless @service
  return if array_typed?(node)
  default = mutable_default(node)
  return unless default

  source = default.source
  add_offense(default, message: format(MSG, source: source)) do |corrector|
    corrector.replace(default, "-> { #{source} }")
  end
end