40 lines
1010 B
Ruby
40 lines
1010 B
Ruby
module RuboCop
|
|
module Cop
|
|
module Gitlab
|
|
class PredicateMemoization < RuboCop::Cop::Cop
|
|
MSG = <<~EOL.freeze
|
|
Avoid using `@value ||= query` inside predicate methods in order to
|
|
properly memoize `false` or `nil` values.
|
|
https://docs.gitlab.com/ee/development/utilities.html#strongmemoize
|
|
EOL
|
|
|
|
def on_def(node)
|
|
return unless predicate_method?(node)
|
|
|
|
select_offenses(node).each do |offense|
|
|
add_offense(offense, location: :expression)
|
|
end
|
|
end
|
|
|
|
private
|
|
|
|
def predicate_method?(node)
|
|
node.method_name.to_s.end_with?('?')
|
|
end
|
|
|
|
def or_ivar_assignment?(or_assignment)
|
|
lhs = or_assignment.each_child_node.first
|
|
|
|
lhs.ivasgn_type?
|
|
end
|
|
|
|
def select_offenses(node)
|
|
node.each_descendant(:or_asgn).select do |or_assignment|
|
|
or_ivar_assignment?(or_assignment)
|
|
end
|
|
end
|
|
end
|
|
end
|
|
end
|
|
end
|