Consistent Nested F-String with Python >= 3.12

[TheSkyentist]

Python 3.12 and newer allow one to nest F-String using the same quotation mark. Is there a way to get ruff to format your document to do this? E.g.

f’{‘abc’[0]}’ currently formats to f”{‘abc’[0]}” rather than going to two double quotes.

Perhaps I am missing an option if it exists. Ideally it would use what you’ve set in “quote-style”.

[ntBre]

You can achieve this with a target-version of Python 3.12 or higher and quote-style = "preserve":

echo "f'{'abc'[0]}'" > example.py

ruff format \
    --no-cache \
    --config 'target-version = "py312"' \
    --config 'format.quote-style = "preserve"' \
    --diff example.py

Unfortunately, preserve has the downside of not changing any quotes, but otherwise the formatter currently prefers alternating quotes for f-strings unless the outer quotes are tripled.

There's also an open feature request for this to be added as an option at #14118, so we're still keeping it in mind!

[ntBre]

Oh, just to clarify, my example will preserve both sets of single quotes, not convert them both to double quotes as you asked. All of the quotes would have to start out as double quotes to be preserved, like f"{"abc"[0]}". Hopefully the rest of the context is still helpful!

[TheSkyentist]

Thanks for the information! I’ll subscribe to the issue and use these workarounds in the meantime. :-)