Composer dependencies with dependencies on root cannot be resolved

The env var seems to have solved my specific problem in https://git.drupalcode.org/project/symfony_messenger/-/merge_requests/4

In order to test, you can change your `.gitlab-ci.yml` template to point to this MR:

include:
  - project: issue/gitlab_templates-3390895
    ref: 3390895-composer-root-version
    file:
      - '/includes/include.drupalci.main.yml'
      - '/includes/include.drupalci.variables.yml'
      - '/includes/include.drupalci.workflows.yml'

Needs review.

Given that core uses this variable to run some tests and that the exact change can be found in the templates in core (https://git.drupalcode.org/project/drupal/-/blob/11.x/.gitlab-ci.yml?ref...) I will commit this addition shortly.

Actually, COMPOSER_ROOT_VERSION needs to be relative to Drupal core, NOT the branch of the contrib module, otherwise it will try to install Drupal core "8.x-1.x-dev" for example, where "8.x-1.x" is the branch of the contrib module.

See here: https://git.drupalcode.org/project/keycdn/-/jobs/228545

The system is alerting when we have this situation, which is correct, but I'm not sure we should try to fix it in these templates as I cannot think of a logic that will always work for each contrib module branch and core needs.

The suggestion to fix this would be to add:
COMPOSER_ROOT_VERSION: "${CORE_SUPPORTED}" (or whichever version you need) to the .composer-base:variables section, or the composer (... major) jobs if these are enabled.

Each contrib module might have different needs on this regarding the Drupal version that is used, so I think that the templates shouldn't do any assumption.

I did some suggestions in #3190024: Problem with test dependencies when testing issue forks → with some code samples.

As this is "won't fix" could you close MR52 please?

fjgarlin → closed merge request !52