Allow to add a comment when submitting a MR review (batch comments)

Problem to solve

People have complained that sometimes they re-assign the MR to the author without submitting a review.

Having the option to add a comment when the review is submitted, allowing the reviewer to re-assign on submission would cover a very common step in MR reviews and make this feature more resilient in terms of behaviour.

@zj voiced this on slack:

I don't use it anymore, as I've assigned a MR back a few times without posting the notes. I'd like a /submit_review quick action too, as that way the 'thanks for this MR, few minor notes' message can be posted at the same time as the actual notes

Intended users

Further details

Proposal

  1. Add comments to review in MR
  2. Submit the review.
  3. While reviewing the comments, you can add a typical "thanks for the MR, few minor notes" comment.
  4. You can also add a quickaction to re-assign to someone.

Screen_Shot_2019-04-04_at_12.08.33

Documentation

Should update the MR Reviews section: https://docs.gitlab.com/ee/user/discussions/index.html#merge-request-reviews-premium

What does success look like, and how can we measure that?

Higher usage of Reviews could be a result of this, as we've heard a few cases of ppl dropping the feature altogether.

Links / references

Edited by André Luís