added test for selection globs with many files under

tests/integration/test_storage_s3/test.py

@@ -678,6 +678,44 @@ def test_s3_glob_scheherazade(started_cluster):
     assert run_query(instance, query).splitlines() == ["1001\t1001\t1001\t1001"]
 
 
+# a bit modified version of scheherazade test
+# checks e.g. `prefix{1,2}/file*.csv`, where there are more than 1000 files under each of prefix1, prefix2.
+def test_s3_glob_many_objects_under_selection(started_cluster):
+    bucket = started_cluster.minio_bucket
+    instance = started_cluster.instances["dummy"]  # type: ClickHouseInstance
+    table_format = "column1 UInt32, column2 UInt32, column3 UInt32"
+    values = "(1, 1, 1)"
+    jobs = []
+    for file_num in range(1100):
+
+        def create_files(file_num):
+            for folder_num in range(1, 3):
+                path = f"folder{folder_num}/file{file_num}.csv"
+                query = "insert into table function s3('http://{}:{}/{}/{}', 'CSV', '{}') values {}".format(
+                    started_cluster.minio_ip,
+                    MINIO_INTERNAL_PORT,
+                    bucket,
+                    path,
+                    table_format,
+                    values,
+                )
+                run_query(instance, query)
+
+        jobs.append(threading.Thread(target=create_files, args=(file_num,)))
+        jobs[-1].start()
+
+    for job in jobs:
+        job.join()
+
+    query = "select count(), sum(column1), sum(column2), sum(column3) from s3('http://{}:{}/{}/folder{{1,2}}/file*.csv', 'CSV', '{}')".format(
+        started_cluster.minio_redirect_host,
+        started_cluster.minio_redirect_port,
+        bucket,
+        table_format,
+    )
+    assert run_query(instance, query).splitlines() == ["2200\t2200\t2200\t2200"]
+
+
 def run_s3_mocks(started_cluster):
     script_dir = os.path.join(os.path.dirname(__file__), "s3_mocks")
     start_mock_servers(