I'm leaning towards the py command implicitly detecting the block of TOML and doing the "right" thing automatically. The other option is making the functionality opt-in via a py run subcommand. I don't see enough benefit to warrant the subcommand, but I figured I would gut-check this in case I'm missing some workflow where this would be a concern.
@brettcannon What's the right thing, though?
If it's to silently create/update an isolated venv for that specific script, I'll think twice about using /// script. Especially with hefty dependencies like NumPy or Qt.
And if it asks by default, you might be turning scripts meant for unattended execution into interactive CLI apps.
@encukou To be clear, any installation would be into a virtual environment in your /tmp directory, so nothing is being trampled or permanently kept. So if pip does the right thing in that instance then you would get what you want.
@brettcannon That sounds close to the right thing!
Beware that /tmp is a ramdisk by default on many modern distros. You don't want to install Tensorflow there. You probably want to use $XDG_STATE_HOME (~/.local/state), and clean it periodically.
@brettcannon I feel that any command that can do anything extra should be clearly different from the usual command.
Consider a project that comes with helper scripts. It should be clear that running those scripts may install additional dependencies and should be more closely vetted. A distinct command will serve to make that possibility more clear.
@zech It is clear if you read the source which you should do, else the script could do something nuts like https://pip.wtf/ regardless of PEP 723 and thus the command makes no difference.
@brettcannon either way I would normally expect py to run in an environment I had already built. I would want to explicitly confirm downloading and installing things, e.g. because py or py run detected the block and asked me to confirm.
@brettcannon I mean I would not expect a tool to install new things without explicit permission - "pip install" or "conda install" explicitly says please install some stuff. "py myfile.py". Even if I read the file I might not expect the comments to have the side effect of downloading, installing and running code. (thinking as a general python user, e.g. my colleagues, rather than someone who has read the pep, ie me)
@graham_knapp To be clear, any installation would be into a virtual environment in your /tmp directory, so nothing is being trampled or permanently kept.
@brettcannon I think part of my unease comes from "py" sounding like a shortcut for python (which it kind of is on Windows) and part comes from the existing "py my_script.py" command taking on a different behaviour.
Add comment