Fix cache_collection crashing when given an empty collection (#15921)

* Fix cache_collection crashing when given an empty collection * Add tests
2021-03-18 00:41:32 +01:00
parent 43eff898a0
commit 5027abecd1
4 changed files with 65 additions and 2 deletions
--- a/app/controllers/concerns/cache_concern.rb
+++ b/app/controllers/concerns/cache_concern.rb
@ -31,7 +31,9 @@ module CacheConcern
  def cache_collection(raw, klass)
    return raw unless klass.respond_to?(:with_includes)

-    raw                    = raw.cache_ids.to_a if raw.is_a?(ActiveRecord::Relation)
+    raw = raw.cache_ids.to_a if raw.is_a?(ActiveRecord::Relation)
+    return [] if raw.empty?
+
    cached_keys_with_value = Rails.cache.read_multi(*raw).transform_keys(&:id)
    uncached_ids           = raw.map(&:id) - cached_keys_with_value.keys