Describe using a dry-run merge early in MR jobs

What does this MR do?

This merge request captures a question and answer from an internal resource. What's here is incomplete. My plan: create a stub, and send this MR over to the person who originally answered the question.

Goal: a full, usable answer we can publish.

Question: We use merged request pipelines (https://docs.gitlab.com/ee/ci/pipelines/merge_request_pipelines.html), but there is one situation that keeps cropping up:
When an MR is in a conflicting state with its target branch, the merge doesn't take place but CI pipelines are still created.
I'd like to know if any env vars are set that we can use to abort these pipelines because they are misleading because they'll probably be out of date and often lead to confusion.

Answer: There is always the possibility to run in your first mr pipeline a dry run merge to target branch and depending on result fail the pipeline.

Related issues

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