Merge pull request #32414 from bogdan/query-cache-optimization

Optimize the code inside AR::QueryCache middleware

activerecord/lib/active_record/query_cache.rb

@@ -26,19 +26,12 @@ def uncached(&block)
     end
 
     def self.run
-      ActiveRecord::Base.connection_handler.connection_pool_list.map do |pool|
-        caching_was_enabled = pool.query_cache_enabled
-
-        pool.enable_query_cache!
-
-        [pool, caching_was_enabled]
-      end
+      ActiveRecord::Base.connection_handler.connection_pool_list.
+        reject { |p| p.query_cache_enabled }.each { |p| p.enable_query_cache! }
     end
 
-    def self.complete(caching_pools)
-      caching_pools.each do |pool, caching_was_enabled|
-        pool.disable_query_cache! unless caching_was_enabled
-      end
+    def self.complete(pools)
+      pools.each { |pool| pool.disable_query_cache! }
 
       ActiveRecord::Base.connection_handler.connection_pool_list.each do |pool|
         pool.release_connection if pool.active_connection? && !pool.connection.transaction_open?

activerecord/test/cases/query_cache_test.rb

@@ -441,8 +441,9 @@ def test_query_cache_is_enabled_on_connections_established_after_middleware_runs
       assert_not ActiveRecord::Base.connection_handler.active_connections? # sanity check
 
       middleware {
-        assert ActiveRecord::Base.connection.query_cache_enabled, "QueryCache did not get lazily enabled"
+        assert_predicate ActiveRecord::Base.connection, :query_cache_enabled
       }.call({})
+      assert_not_predicate ActiveRecord::Base.connection, :query_cache_enabled
     end
   end