('0xdc', '32M',       '32k'), # Left-end of partial-right [2]
              ('0xcd', '0x3ff0000', '64k')] # patterns[3]
 
-with iotests.FilePath('base.img') as base_img_path, \
-     iotests.FilePath('fleece.img') as fleece_img_path, \
-     iotests.FilePath('nbd.sock',
-                      base_dir=iotests.sock_dir) as nbd_sock_path, \
-     iotests.VM() as vm:
-
+def do_test(base_img_path, fleece_img_path, nbd_sock_path, vm):
     log('--- Setting up images ---')
     log('')
 
 
     log('')
     log('Done')
+
+
+def test():
+    with iotests.FilePath('base.img') as base_img_path, \
+         iotests.FilePath('fleece.img') as fleece_img_path, \
+         iotests.FilePath('nbd.sock',
+                          base_dir=iotests.sock_dir) as nbd_sock_path, \
+         iotests.VM() as vm:
+        do_test(base_img_path, fleece_img_path, nbd_sock_path, vm)
+
+
+test()