For our project we are using gitlab-ce and Jenkins to build docker images. I'm using a Pipeline Jenkinsfile to build my docker
I suppose my jenkins job is correctly configured since the build is triggered each time I push a commit or a tag into my gitlab project
 In my pipeline, I have a stage I wish to be called only when a tag is pushed (git push --tag)}}
I added the following line:
   when

     { buildingTag() }

But every time I push a tag in gitlab, I have the message Stage skipped due to when conditional

Attached the Jenkinsfile I'm using

Context

• Gitlab plugin version: 1.5.11
• Gitlab CE version: 11.2.0
• Jenkins version: 2.163
• Job type: Pipeline (the pipeline plugins are up to date)

Our Jenkins docker container is based on image jenkins/jenkins:2.163-alpine

Attached the console output triggered when after the push of a tag using the command:

git push --tag origin master

Is there something special to do to use the when tag or when buildingTag ? It seems to me I have done everything according to the documentation