RUF032 fix can produce strings that are invalid for Decimal

[dscorbett]

RUF032 produces an invalid string argument when the existing argument is a float with multiple unary operators. Decimal’s string parser only accepts one sign character.

$ ruff --version
ruff 0.6.4
$ cat ruf032.py
from decimal import Decimal
Decimal(++0.3)
$ ruff check --isolated --preview --select RUF032 ruf032.py --unsafe-fixes --fix
Found 1 error (1 fixed, 0 remaining).
$ python ruf032.py 2>&1 | tail -n 2
    Decimal("++0.3")
decimal.InvalidOperation: [<class 'decimal.ConversionSyntax'>]

RUF032 also stringifies the argument if it is a float with the ~ unary operator. Applying ~ to a float raises a TypeError and should never happen, but if someone does write that, it is probably not helpful to convert it to a string, which makes it raise a different error that the surrounding code might not be expecting.

$ cat ruf032_error.py
from decimal import Decimal
Decimal(~1.0)
$ python ruf032_error.py 2>&1 | tail -n 3
    Decimal(~1.0)
            ^^^^
TypeError: bad operand type for unary ~: 'float'
$ ruff check --isolated --preview --select RUF032 ruf032_error.py --unsafe-fixes --fix
Found 1 error (1 fixed, 0 remaining).
$ python ruf032_error.py 2>&1 | tail -n 2
    Decimal("~1.0")
decimal.InvalidOperation: [<class 'decimal.ConversionSyntax'>]