PyPy's zipimporter doesn't have the _files attribute. 😞 I think I just won't return the template list in that case, rather than trying to traverse the zip file manually.

Implementation on Windows has some path issues, I'll have to address those once I can boot into Windows.

I am not sure this method works with pyinstaller's way of packaging jinja, while mine does :)

importlib.resources is a non-starter as long as it requires __init__.py in every directory and doesn't support directory traversal.

I'm assuming you mean pyinstaller's way of packaging package data, not packaging Jinja, since how Jinja is packaged shouldn't affect how other things are loaded. I'm not familiar with PyInstaller, if you have a simple example of a package with a templates directory, I can take a look.

that's not something very problematic, you know, it is just a file to add. And I recommend letting people decide which method is the best for them. If you need to package jinja in pyinstaller like i do, I am pretty happy with this init.py (it is actually not the more weird thing to do). At least I have the option to choose this loader if I want to.
But it you find a better way to have jinja happy in pyinstaller or similar packaging, I'll be happy to switch

I'm assuming you mean pyinstaller's way of packaging package data, not packaging Jinja, since how Jinja is packaged does not affect how other things are loaded.

Yes, packaging jinja and a template folder as data inside a pyinstaller executable, so that this executable can render the template. I use importlib resource and yes, it's tricky to do, but at least it works

If you need a specific loader for your project, you can always add a loader, we don't need to cover every possible case in the built-in loaders, that's the whole point of it being an interface.

Just checked, PackageLoader with pkg_resources doesn't seem to support PyInstaller's FrozenImporter, so I'm not treating compatibility with PyInstaller as a supported feature.

However, this new implementation does support PyInstaller (unintentionally).

$ tree example/
example
├── __init__.py
└── templates
    └── test.txt
$ pyinstaller -F --name example --add-data example/templates:example/templates entry.py
$ ./dist/example
Hello

-   1
-   2
-   3

World

Great, so it's even simpler that mine :) Will check on it once released !

will this be part of the upcoming release?

Reverting this in 2.11.2, it broke compatibility with Pytest. However, support will be present when 3.0 is released. See #1168, #1169