COM812 breaks conditionals inside multi-line f-strings

[parafoxia]

Synopsis

The COM812 rule is capable of breaking conditional statements within triple f-strings by converting the else-statement into a tuple (or a tuple containing the original tuple).

Of course you can use # noqa: COM812, though I think that linters should be incapable of breaking code.

MRE

(This example assumes the line should be split across multiple lines.)

Original mre.py:

x = f"""This is a test. {
    "Another sentence."
    if True else
    "Alternative route!"
}"""

print(x)

$ py test.py
This is a test. Another sentence.

$ ruff check mre.py
mre.py:4:25: COM812 [*] Trailing comma missing
Found 1 error.
[*] 1 fixable with the `--fix` option.

"Fixed" mre.py

x = f"""This is a test. {
    "Another sentence."
    if True else
    "Alternative route!",
}"""

print(x)

$ py test.py
This is a test. ('Another sentence.',)

$ ruff check mre.py
(Exit code 0)

Environment

• Ruff version: 0.1.3
• Python version: 3.9.11
• OS: macOS Sonoma 14.0

[charliermarsh]

Thanks, I'll take a look at this!

[dhruvmanila]

I think it must be considering the curly braces as ContextType::Dict. It needs to take into account the new f-string tokens and skip if inside a f-string.

[charliermarsh]

@dhruvmanila - Feel free to fix if you're there, I won't get to it for a few hours.

[charliermarsh]

Taking a look now.