per1234 6e18dca644 Adjust release procedure and CI system for "trunk-based" development strategy
Previously, releases were always made from a point in the revision history of the `main` branch (typically the tip of
the branch at the time of the release). Although the simplicity of this approach is nice, it can be limiting in some
cases. For this reason, the project is switching to using a "trunk-based" development strategy, as described here:

https://trunkbaseddevelopment.com/

This approach allows making releases at any time that consist of the arbitrary subset of revisions suitable for shipping
to the users at that time. The commits that should be included in the release are cherry-picked to a release branch and
the tag created on that branch.

This means that:

- PRs can be merged to the `main` branch as soon as they have passed review rather than having to postpone the merge of
  changes that are not ready to be included in the next release.
- Releases don't need to be postponed if the prior revision history on the `main` branch contains changes that are not
  ready to be included in the release.

The documented release procedure must be adjusted to reflect the new development strategy.

CI System Adjustments
---------------------

The status of the GitHub Actions workflows should be evaluated before making a release. However, this is not so simple as
checking the status of the commit at the tip of the release branch. The reason is that, for the sake of efficiency, the
workflows are configured to run only when the processes are relevant to the trigger event (e.g., no need to run unit
tests for a change to the readme).

In the case of the default branch, you can simply set the workflow runs filter to that branch and then check the result
of the latest run of each workflow of interest. However, that was not possible to do with the release branch since it
might be that the workflow was never run in that branch. The status of the latest run of the workflow in the default
branch might not match the status for the release branch if the release branch does not contain the full history.

For this reason, it will be helpful to trigger all relevant workflows on the creation of a release branch. This will
ensure that each of those workflows will always have at least one run in the release branch. Subsequent commits pushed to
the branch can run based on their usual trigger filters and the status of the latest run of each workflow in the branch
will provide an accurate indication of the state of that branch.

Branches are created for purposes other than releases, most notably feature branches to stage work for a pull request.
Due to the comprehensive nature of this project's CI system, it would not be convenient or efficient to fully run all CI
workflows on the creation of every feature branch.

Unfortunately, GitHub Actions does not support filters on the `create` event of branch creation like it does for the
`push` and `pull_request` events. There is support for a `branches` filter of the `push` event, but that filter is an
"AND" to the `paths` filter while this application requires an "OR". For this reason, the workflows must be triggered by
the creation of any branch. The unwanted job runs are prevented by adding a `run-determination` job with the branch
filter handled by Bash commands. The other jobs of the workflow use this `run-determination` job as a dependency, only
running when it indicates they should via a job output. Because this minimal `run-determination` job runs very quickly,
it is roughly equivalent to the workflow having been skipped entirely for non-release branch creations.
2023-06-30 11:31:47 -07:00
..
2022-11-02 15:48:04 +01:00
2022-11-02 15:48:04 +01:00