tpl/os: Add filesystem option to ReadDir

[lukeryannetnz]

This is my first contribution to this project, the issue was labelled as [GoodFirstIssue] so I jumped in. As such, any feedback or guidance 💯 appreciated.

Make ReadDir function variadic. Optional second param specifies FileSystem. The default if not specified remains work dir, to retain backwards compatibility.

I largely followed the breadcrumbs @bep left in the issue comments (thanks!). Things I'm not sure about:

• how best to support the static FS given when in multihost we have one static filesystem per language
• if I need to better test my input checks in os
• how best to update docs (I can spend time looking at this if I get positive feedback on this change)

Fixes #9604

[CLAassistant]

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[bep]

Thanks for this -- the code looks great at first glance. I will need to understand and fix #9609 before I can merge this.

But if I could ask for one change that would make this easier to review:

Instead of creating one test function per variant, I suggest you combine them into one and separate the expectations by an identifier, e.g.:

START  assets:|asset.jpg|:END:
START static:|static.jpg|:END:
...

And if you create an inline template to print this, you get a pretty compact test.

[lukeryannetnz]

Thanks for the feedback, I've combined the tests so they are easier to read as suggested.
Also added a todo to make the gap in the functionality explicit.

I'm a little confused about the failing build, looks like it might have timed out. If you can approve the workflow, I'll look into it if it happens again.

[lukeryannetnz]

Updated test to include a check for composite archetype files.

[lukeryannetnz]

Had a go at adding docs for the new functionality.

[lukeryannetnz]

@bep any interest in taking another look at this?

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This pull request has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.