Issue with Python 3.12 SyntaxWarning: invalid escape sequence docstrings?

[maclermo]

Running on macOS 14, installed using brew and with python3.12:

bash❯ ponysay -v
/usr/local/bin/ponysay/balloon.py:43: SyntaxWarning: invalid escape sequence '\-'
/usr/local/bin/ponysay/balloon.py:43: SyntaxWarning: invalid escape sequence '\-'
ponysay 3.0.3

Program works otherwise. Looks to be in the docstring.

Please follow PEP 257, docstrings should be in triple double-quotes (you are using triple single-quotes).

[Tonyl314]

The warning is fixed in #313.

[maclermo]

See my comment in #313.

[cben]

I'm working on a PR to make tests easier to run but meanwhile, noticed these warnings may mysteriously disappear after first run if running from source. 👻

What's going on is that SyntaxWarning are emitted during bytecode generation, so once e.g. src/__pycache__/balloon.cpython-312.pyc exists, it won't be printed again (python core devs say this effect is known and kinda deliberate).
So if running from source and you want to hit this reproducibly, you can kill the caching:

rm src/__pycache__/ -rf
export PYTHONDONTWRITEBYTECODE=1

This does not happen with the ponysay.install executable which is what end users get, because there the modules are bundled in Zip format, and there is no place to store .pyc for them at runtime. So users do see the warnings every single time.
So another way to test is running e.g.

./setup.py build --freedom=partial --minimal

and then using python3 ./ponysay.install for testing.