gitlab-org--gitlab-foss/rubocop/cop/avoid_becomes.rb

30 lines
1.2 KiB
Ruby

# frozen_string_literal: true
module RuboCop
module Cop
# Cop that blacklists the use of ".becomes(SomeConstant)".
#
# The use of becomes() will result in a new object being created, throwing
# away any eager loaded assocations. This in turn can cause N+1 query
# problems, even when a developer eager loaded all necessary associations.
#
# See https://gitlab.com/gitlab-org/gitlab/-/issues/23182 for more information.
class AvoidBecomes < RuboCop::Cop::Cop
MSG = 'Avoid the use of becomes(SomeConstant), as this creates a ' \
'new object and throws away any eager loaded associations. ' \
'When creating URLs in views, just use the path helpers directly. ' \
'For example, instead of `link_to(..., [group.becomes(Namespace), ...])` ' \
'use `link_to(..., namespace_foo_path(group, ...))`. Most of the time there is no ' \
'need to pass in namespace to the path helpers after implementaton of ' \
'https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/12566'
def_node_matcher :becomes?, <<~PATTERN
(send {send ivar lvar} :becomes ...)
PATTERN
def on_send(node)
add_offense(node, location: :expression) if becomes?(node)
end
end
end
end