Mercurial environment variables for non-branch pipelines
I've noticed that `CI_COMMIT_HG_BRANCH` and similar environment variables are available only for branch pipelines, e.g. notably not "detached" MR pipelines nor tag pipelines.
This lead to some niceties like [empty Docker tags](hgitaly#30) or using [wrong dependencies](heptapod#401). This can often be worked around, e.g., by introducing dedicated match patterns against target GitLab branches in Merge Requests, but that is a bit fuzzy and painful to do.
While it makes sense to consider `CI_COMMIT_BRANCH` to be a fuzzy heuristic at best, and not a cheap one either, it is a clear advantage of Mercurial named branches to be always unambiguously available.
I've go the strong feeling that this has changed with recent GitLab versions.
issue