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src/query/ee/tests/it/storages/fuse/operations/vacuum.rs

@@ -181,14 +181,19 @@ async fn test_fuse_do_vacuum_drop_table_deletion_error() -> Result<()> {
         .options
         .insert(OPT_KEY_DATABASE_ID.to_owned(), "1".to_owned());
 
-    // mocked accessor that will fail to delete dir/files
     use test_accessor::AccessorFaultyDeletion;
+    // Operator with mocked accessor that will fail on `remove_all`
+    //
+    // Note that:
+    // In real case, `Accessor::batch` will be called (instead of Accessor::delete)
+    // but all that we need here is let Operator::remove_all failed
     let faulty_accessor = std::sync::Arc::new(AccessorFaultyDeletion::new());
     let operator = OperatorBuilder::new(faulty_accessor.clone()).finish();
 
     let result = do_vacuum_drop_table(&table_info, &operator, None).await;
     assert!(result.is_err());
     // verify that accessor.delete() was called
+    //
     assert!(faulty_accessor.hit_delete_operation());
 
     Ok(())