diff options
Diffstat (limited to 'rubocop')
| -rw-r--r-- | rubocop/cop/gitlab/predicate_memoization.rb | 39 | ||||
| -rw-r--r-- | rubocop/rubocop.rb | 1 |
2 files changed, 40 insertions, 0 deletions
diff --git a/rubocop/cop/gitlab/predicate_memoization.rb b/rubocop/cop/gitlab/predicate_memoization.rb new file mode 100644 index 00000000000..3c25d61d087 --- /dev/null +++ b/rubocop/cop/gitlab/predicate_memoization.rb @@ -0,0 +1,39 @@ +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 diff --git a/rubocop/rubocop.rb b/rubocop/rubocop.rb index 57af87f7fb9..9110237c538 100644 --- a/rubocop/rubocop.rb +++ b/rubocop/rubocop.rb @@ -1,4 +1,5 @@ require_relative 'cop/gitlab/module_with_instance_variables' +require_relative 'cop/gitlab/predicate_memoization' require_relative 'cop/include_sidekiq_worker' require_relative 'cop/line_break_around_conditional_block' require_relative 'cop/migration/add_column' |