Specify an :inverse_of
option. Open
has_many :taggings, as: :subject, dependent: :destroy
- Read upRead up
- Exclude checks
This cop looks for has(one|many) and belongsto associations where
ActiveRecord can't automatically determine the inverse association
because of a scope or the options used. This can result in unnecessary
queries in some circumstances. :inverse_of
must be manually specified
for associations to work in both ways, or set to false
to opt-out.
Example:
# good
class Blog < ApplicationRecord
has_many :posts
end
class Post < ApplicationRecord
belongs_to :blog
end
Example:
# bad
class Blog < ApplicationRecord
has_many :posts, -> { order(published_at: :desc) }
end
class Post < ApplicationRecord
belongs_to :blog
end
# good
class Blog < ApplicationRecord
has_many(:posts,
-> { order(published_at: :desc) },
inverse_of: :blog
)
end
class Post < ApplicationRecord
belongs_to :blog
end
# good
class Blog < ApplicationRecord
with_options inverse_of: :blog do
has_many :posts, -> { order(published_at: :desc) }
end
end
class Post < ApplicationRecord
belongs_to :blog
end
Example:
# bad
class Picture < ApplicationRecord
belongs_to :imageable, polymorphic: true
end
class Employee < ApplicationRecord
has_many :pictures, as: :imageable
end
class Product < ApplicationRecord
has_many :pictures, as: :imageable
end
# good
class Picture < ApplicationRecord
belongs_to :imageable, polymorphic: true
end
class Employee < ApplicationRecord
has_many :pictures, as: :imageable, inverse_of: :imageable
end
class Product < ApplicationRecord
has_many :pictures, as: :imageable, inverse_of: :imageable
end
Example:
# bad
# However, RuboCop can not detect this pattern...
class Physician < ApplicationRecord
has_many :appointments
has_many :patients, through: :appointments
end
class Appointment < ApplicationRecord
belongs_to :physician
belongs_to :patient
end
class Patient < ApplicationRecord
has_many :appointments
has_many :physicians, through: :appointments
end
# good
class Physician < ApplicationRecord
has_many :appointments
has_many :patients, through: :appointments
end
class Appointment < ApplicationRecord
belongs_to :physician, inverse_of: :appointments
belongs_to :patient, inverse_of: :appointments
end
class Patient < ApplicationRecord
has_many :appointments
has_many :physicians, through: :appointments
end
@see http://guides.rubyonrails.org/association_basics.html#bi-directional-associations @see http://api.rubyonrails.org/classes/ActiveRecord/Associations/ClassMethods.html#module-ActiveRecord::Associations::ClassMethods-label-Setting+Inverses
Models should subclass ApplicationRecord
. Open
class Project < ActiveRecord::Base
- Read upRead up
- Exclude checks
This cop checks that models subclass ApplicationRecord with Rails 5.0.
Example:
# good class Rails5Model < ApplicationRecord # ... end
# bad class Rails4Model < ActiveRecord::Base # ... end
Missing magic comment # frozen_string_literal: true
. Open
# == Schema Information
- Read upRead up
- Exclude checks
This cop is designed to help upgrade to Ruby 3.0. It will add the
comment # frozen_string_literal: true
to the top of files to
enable frozen string literals. Frozen string literals may be default
in Ruby 3.0. The comment will be added below a shebang and encoding
comment. The frozen string literal comment is only valid in Ruby 2.3+.
Example: EnforcedStyle: when_needed (default)
# The `when_needed` style will add the frozen string literal comment
# to files only when the `TargetRubyVersion` is set to 2.3+.
# bad
module Foo
# ...
end
# good
# frozen_string_literal: true
module Foo
# ...
end
Example: EnforcedStyle: always
# The `always` style will always add the frozen string literal comment
# to a file, regardless of the Ruby version or if `freeze` or `<<` are
# called on a string literal.
# bad
module Bar
# ...
end
# good
# frozen_string_literal: true
module Bar
# ...
end
Example: EnforcedStyle: never
# The `never` will enforce that the frozen string literal comment does
# not exist in a file.
# bad
# frozen_string_literal: true
module Baz
# ...
end
# good
module Baz
# ...
end
Prefer annotated tokens (like %<foo>s</foo>
) over template tokens (like %{foo}
). Open
validates :title, presence: true, uniqueness: { message: '%{value} is already used' }
- Read upRead up
- Exclude checks
Use a consistent style for named format string tokens.
Note:
unannotated
style cop only works for strings
which are passed as arguments to those methods:
sprintf
, format
, %
.
The reason is that unannotated format is very similar
to encoded URLs or Date/Time formatting strings.
Example: EnforcedStyle: annotated (default)
# bad
format('%{greeting}', greeting: 'Hello')
format('%s', 'Hello')
# good
format('%<greeting>s', greeting: 'Hello')</greeting>
Example: EnforcedStyle: template
# bad
format('%<greeting>s', greeting: 'Hello')
format('%s', 'Hello')
# good
format('%{greeting}', greeting: 'Hello')</greeting>
Example: EnforcedStyle: unannotated
# bad
format('%<greeting>s', greeting: 'Hello')
format('%{greeting}', 'Hello')
# good
format('%s', 'Hello')</greeting>