add delete sync block and test case

[jackzhhuang]

Pull request type

Please check the type of change your PR introduces:

• [ ] Bugfix
• [ ] Feature
• [ ] Code style update (formatting, renaming)
• [ ] Refactoring (no functional changes, no api changes)
• [ ] Build related changes
• [ ] Documentation content changes
• [ ] Other (please describe):

What is the current behavior?

Issue Number: N/A

What is the new behavior?

-

-

Other information

[nkysg]

Please use rebase not merge.