Bug report

Bug description:

If you read a config with an empty unnamed section using ConfigParser with allow_unnamed_section set to True and write it back, the resulting file will contain an extra newline at the beginning:

from configparser import ConfigParser
from io import StringIO
cfg = ConfigParser(allow_unnamed_section=True)
cfg.read_string('[sect]')
output = StringIO()
cfg.write(output)
print(repr(output.getvalue())) # '\n[sect]\n\n'

CPython versions tested on:

3.13

Operating systems tested on:

Windows

Linked PRs

• gh-129678: ConfigParser: do not write an empty unnamed section #129679