Previously I am using gerrt and now quite new to gitlab. One question is that does gitlab have the idea of "patch set" concept which is in gerrit?
The problem is that developer working on feature branch seems to need a new commit to update a merge request, which would leave many git commit in a single merge request. And final merge operation would merge all the commits from a feature branch to master branch, while many middle commits are actually not need to push(e.g.: address the patch review comments).
In gerrit one commit could be amended and updated by many patch-set, and final merge request only push one commit in the end.