What is your template development workflow?

[up-stevesloan]

First of all - thank you all for such a wonderful tool!

Goal

I'm looking for best practices on development workflow. Specifically, how to develop changes to the template in the context of (a) project(s). I'd like to avoid "hope it works" PRs to the template repo.

Sincere apologies if this is documented somewhere... closest I could find was copying dirty changes.

Background

Scenario is pretty typical I think:

• template is in a repo, changes require PR
• projects are each in their own repo, changes require PR
• multiple developers, each of whom clone the template and project repos locally for dev work

Once you know that a change to the template is good, it's easy enough to run copier update... but:

Questions

I want to add a feature or refactor something in the template repo, and know it's going to work in a project repo before I PR the change to the template repo. What's the workflow for this?

Commentary

If folks are using this workflow, it seems it would need to go something like this

1. Change your cloned project's .copier_answers.yml to point to your clone of the template (e.g. GitHub URL swapped for local filesystem path)
2. Edit the template clone's code locally
3. Switch to the project repo clone and run copier update and test
4. repeat the last 2 steps until satisfied with the new template feature
5. PR template changes
6. revert project .copier_answers.yml changes
7. run a final copier update in the project
8. PR project changes

However the above violates https://copier.readthedocs.io/en/stable/updating/#never-change-the-answers-file-manually so that does not seem like best practice. Perhaps I'm missing some way to update the project repo, overriding the _src_path so it pulls the template from the local filesystem instead of from GH.

[chazmo03]

If you have write access to the remote template repo, you can push the template changes in a feature branch and run copier update --vcs-ref feature-branch in your project repo.

[up-stevesloan]

Thanks @chazmo03! Fair point, I guess I was pretty focused on staying local, but this can work, and avoids "hope it works" PRs in the template repo. Also has the benefit of enabling collaborators to test your template changes!

[pawamoy]

So, it's not easiest setup, but here's my workflow:

• I have a script that tests the template
• this script generates a temp project under tests/tmp (from HEAD, which tells Copier will include dirty changes): copier copy -f --trust -r HEAD . tests/tmp
• then it enters the generated project and does lots of things:
  • git init and add existing remote (https://github.com/pawamoy/pawamoy-testing/)
  • cleans up tag in copier answers
  • git add everything, commit and tag 0.1.0
  • test the project's commands (depends on the template), for example:
    • running make format and checking that nothing changed
    • running make test to see if generated tests pass
    • creating a dummy fix commit to see if make changelog and make release work as expected
• I have a second script that "resets" the Git history of the testing repository, regenerates the project from the template, and pushes to trigger its own CI on GitHub
• this script then queries GitHub in a loop to wait for the CI to pass
• in the template CI, I run both scripts

Here's my template: https://github.com/pawamoy/copier-uv. Maybe start by reading .github/workflows/ci.yml if you want to see how it works in details.

[up-stevesloan]

Thanks @pawamoy! I will check it out.