Fix ClosedQueueError in AsyncDataloader

spec/graphql/dataloader/async_dataloader_spec.rb

@@ -389,5 +389,70 @@ class TraceAsyncSchema < AsyncSchema
         check_snapshot(data, if_exec_next("example-next.json", "example.json"))
       end
     end
+
+    if testing_rails? && ISOLATION_LEVEL_FIBER
+      describe "with activerecord" do
+        class ActiveRecordAsyncSchema < GraphQL::Schema
+          class Author < GraphQL::Schema::Object
+            field :name, String
+          end
+
+          class Book < GraphQL::Schema::Object
+            field :title, String
+            field :author, Author
+          end
+
+          Author.field(:books, Book.connection_type)
+
+          class Query < GraphQL::Schema::Object
+            field :book, Book do
+              argument :title, String
+            end
+
+            def book(title:)
+              dataload_record(::Book, title, find_by: :title)
+            end
+
+            field :author, Author do
+              argument :name, String
+            end
+
+            def author(name:)
+              dataload_record(::Author, name, find_by: :name)
+            end
+          end
+
+          query(Query)
+          use GraphQL::Dataloader::AsyncDataloader
+        end
+
+        it "works with repeated queries" do
+          query_str = <<~GRAPHQL
+          {
+            author(name: "William Shakespeare") { name }
+            b1: book(title: "A Midsummer Night's Dream") { title author { name } }
+            b2: book(title: "Hamlet") { title author { name } }
+          }
+          GRAPHQL
+
+          results = []
+          10.times do
+            stdout, stderr = capture_io do
+              result = ActiveRecordAsyncSchema.execute(query_str)
+              results << [
+                result["data"]["author"]["name"],
+                result["data"]["b2"]["title"]
+              ]
+            end
+            assert_equal "", stdout, "Nothing to stdout"
+            assert_equal "", stderr, "Nothing to stderr (like warnings from Task errors)"
+          rescue
+            :failed
+          end
+
+          assert_equal Array.new(10, ["William Shakespeare", "Hamlet"]), results
+        end
+      end
+    end
   end
 end

spec/integration/rails/graphql/dataloader/async_dataloader_spec.rb

@@ -89,7 +89,7 @@ def role
   end
 
   before {
-    skip("Only test when isolation_level = :fiber") unless ENV["ISOLATION_LEVEL_FIBER"]
+    skip("Only test when isolation_level = :fiber") unless ISOLATION_LEVEL_FIBER
   }
 
   it "cleans up database connections" do

spec/integration/rails/spec_helper.rb

@@ -10,9 +10,12 @@
   require "sqlite3"
 end
 
-if ENV["ISOLATION_LEVEL_FIBER"]
+ISOLATION_LEVEL_FIBER = if ENV["ISOLATION_LEVEL_FIBER"]
   ActiveSupport::IsolatedExecutionState.isolation_level = :fiber
   puts "ActiveSupport::IsolatedExecutionState: #{ActiveSupport::IsolatedExecutionState.isolation_level}"
+  true
+else
+  false
 end
 
 require_relative "generators/base_generator_test"