As of today it's already possible to create a GitLab branch in a repository from a Tuleap artifact.
The goal of this user story is to be able to create the corresponding Merge Request in the same time.
In artifact "Action" menu:
- The label "Create a new GitLab branch" is renamed "Create a new GitLab branch or MR"
- In the popup, there is a checkbox "[X] create corresponding MR" that is ticked by default
- When the box is ticked, the branch is created, the MR is created was well with "Draft" status.
- Title of the MR is the title of the artifact: "TULEAP-XYZ: $TITLE"
- There is no description
No change in permission scheme: user creating the merge request must be member of the project containing the artifact (see art #21336).