Add contribution documentation on how to build/test template changes

[freakboy3742]

What is the problem or limitation you are having?

Briefcase's contribution guide describes how to modify Briefcase's own code, but isn't clear on how to build and test changes to the templates that Briefcase uses.

Describe the solution you'd like

A new contribution section in Briefcase's docs that details:

• The range of templates that are used at runtime by Briefcase (i.e., the beeware/briefcase-template repo, and all the beeware/briefcase-<platform>-<format>-template repos)
• How to use briefcase new --template ... --template-branch to point at a modified wizard template
• How to use template and template_branch configuration items to point at a modified platform template
• How to handle the case where the template change also requires changes in Briefcase (i.e., using the briefcase-repo: and briefcase-ref: values in the PR body)

Describe alternatives you've considered

Additional context

This discussion gives a very high level overview on how to use template and template_branch.

[Slavaqq]

Hello, I am going to look at this issue.

[kshivani06]

Hi, I’m new to BeeWare and interested in contributing to Briefcase. I see there hasn’t been recent activity on this issue — is it still open for contribution? I’d be happy to work on it.

[kattni]

@kshivani06 Welcome to BeeWare! Yes, this is still available. We don't assign issues directly, so your comment here is enough to say that you'll be working on it.

A lot has changed with the contribution guides since this issue was submitted. I would suggest getting some clarification from @freakboy3742 on what the expectation is at this point. He'll be able to reply at some point in the next day or so.

In the meantime, you can take a look at the new documentation contribution guide to get your development environment set up and get the docs building. I'm happy to answer any questions you have on that process.

[kshivani06]

Thanks for the clarification! I’ll review the current documentation contribution guide and get the docs building locally. I’ll also wait for further guidance from @freakboy3742 on expectations.

[freakboy3742]

Hi @kshivani06!

The change that @kattni refers to is a consolidation across BeeWare projects - the contribution guides for all our projects are all mostly the same, but some projects have some additions and customizations reflecting project-specific concerns. The documentation described by this ticket would be one of those changes.

In this case, what is required is some extra content in docs/en/how-to/contribute/how/write_code.md. Add the following:

{% block testing_additional %}
### Briefcase specific content

This is some additional Briefcase testing content
{% endblock %}

Just above the end_matter block, and then re-build the docs as described in the new docs contribution guide - you should see the "Writing, running and testing code" page now has the extra "Briefcase specific content" section.

Then you can work on the specific content. Let us know if you need any additional pointers!