Fix issue with cached partial collections

actionview/CHANGELOG.md

@@ -1,3 +1,24 @@
+*   Fix issue with cached partial collections
+
+    It's possible to render a collection of partials with the `cached: true`
+    parameter, each of which are also cached.  If those partials also
+    have an `expires_in` value for their cache lifetime.  Because of the 
+    key collision between the partial's cache key and the individual
+    collection elements' cache key, the non-expiring version will win.
+
+    Fix is to allow cache parameters (well, only `expires_in`) to be passed
+    allong with the cache collection render call. i.e., from:
+
+    <%= render :partial => 'test/test', :collection => @models, :as => :test, :cached => true %>
+
+    to:
+
+    <%= render :partial => 'test/test2', :collection => @models, :as => :test, :cached => true, :expires_in => 5.seconds %>
+
+    For #33424
+
+    *Iain Bryson*
+
 *   Deprecate calling private model methods from view helpers.
 
     For example, in methods like `options_from_collection_for_select`

actionview/lib/action_view/renderer/partial_renderer/collection_caching.rb

@@ -14,6 +14,7 @@ module CollectionCaching # :nodoc:
       def cache_collection_render(instrumentation_payload)
         return yield unless @options[:cached]
 
+        @cache_options = @options.slice(:expires_in) # REVIEW: is Ruby 2.5-requiring code allowed here?
         keyed_collection = collection_by_cache_keys
         cached_partials  = collection_cache.read_multi(*keyed_collection.keys)
         instrumentation_payload[:cache_hits] = cached_partials.size
@@ -22,7 +23,7 @@ def cache_collection_render(instrumentation_payload)
         rendered_partials = @collection.empty? ? [] : yield
 
         index = 0
-        fetch_or_cache_partial(cached_partials, order_by: keyed_collection.each_key) do
+        fetch_or_cache_partial(cached_partials, order_by: keyed_collection.each_key, cache_options: @cache_options) do
           rendered_partials[index].tap { index += 1 }
         end
       end
@@ -44,11 +45,11 @@ def expanded_cache_key(key)
         key.frozen? ? key.dup : key # #read_multi & #write may require mutability, Dalli 2.6.0.
       end
 
-      def fetch_or_cache_partial(cached_partials, order_by:)
+      def fetch_or_cache_partial(cached_partials, order_by:, cache_options:)
         order_by.map do |cache_key|
           cached_partials.fetch(cache_key) do
             yield.tap do |rendered_partial|
-              collection_cache.write(cache_key, rendered_partial)
+              collection_cache.write(cache_key, rendered_partial, cache_options)
             end
           end
         end