tokudb.dir_per_db_rename_to_nonexisting_schema failed in buildbot on DROP DATABASE

tokudb.dir_per_db_rename_to_nonexisting_schema w2 [ fail ]

        Test ended at 2017-10-19 05:35:44

CURRENT_TEST: tokudb.dir_per_db_rename_to_nonexisting_schema

mysqltest: At line 20: query 'DROP DATABASE new_db' failed: 1010: Error dropping database (can't rmdir './new_db', errno: 39 "Directory not empty")

The result from queries just before the failure was:

SET GLOBAL tokudb_dir_per_db=true;

######

# Tokudb and mysql data dirs are the same, rename to existent db

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CREATE DATABASE new_db;

CREATE TABLE t1 (id INT AUTO_INCREMENT PRIMARY KEY NOT NULL) ENGINE=tokudb;

ALTER TABLE test.t1 RENAME new_db.t1;

The content of "test" directory:

The content of "new_db" directory:

db.opt

t1.frm

t1_main_id.tokudb

t1_status_id.tokudb

DROP DATABASE new_db;