MergeRequest class is not working

[raphaelbadia]

Context

• Gitlab plugin version: X.Y.Z
• Gitlab version: 11.7.4
• Jenkins version: 2.204.1
• Job type: Pipeline

Logs & Traces

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Problem description

In a pipeline groovy script we use createMergeRequest to automatically create merge requests to a branch.

I saw here that createMergeRequest returns a MergeRequest class, which has the methods setLabels and setAssignee.

We have a pipeline that creates a new merge request back to develop every time a hotfix is pushed to master :

My grrovy script looks like:

#!groovy
import static com.dabsquared.gitlabjenkins.connection.GitLabConnectionProperty.getClient;

def createMergeBackMR() {
   // ....
    def mr = gitLabClient.createMergeRequest(projectId, targetBranch, newMRTarget, "Merge back $targetBranch -> $newMRTarget");
    mr.setLabels(["PAT", "MERGE BACK"]);
    // mr.setAssignee("rbadia") // needs a User but don't know how to instanciate it
}

node {
    createMergeBackMR();
}

The merge request is created successfully, but no labels are set. Did I miss something ?

Sorry if the question is stupid, I don't do java / groovy / devops at all usually. I have no idea on how this works...

Thanks !