id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
37442	JSONL deserializer incorrectly treats Unicode line separators as record boundaries	Patel Namraa	Patel Namraa	"The JSONL deserializer incorrectly uses `str.splitlines()` to split string and bytes input into records. `splitlines()` treats U+2028 (LINE SEPARATOR), U+2029 (PARAGRAPH SEPARATOR), and U+0085 (NEXT LINE) as line boundaries, even though these characters can occur unescaped inside JSON strings.

The JSONL serializer uses `ensure_ascii=False`, so these characters can be emitted directly in serialized JSON. As a result, data produced by Django's JSONL serializer cannot always be deserialized again when a serialized value contains one of these characters.

For example:

{{{
from django.core import serializers
from myapp.models import Author

author = Author(pk=1, name=""Jane\u2028Doe"")
data = serializers.serialize(""jsonl"", [author])
list(serializers.deserialize(""jsonl"", data))
}}}

This raises `DeserializationError` because the record is split at U+2028 instead of only at the JSONL record delimiter.

The same behavior occurs with U+2029 and U+0085, and with both `str` and `bytes` input.

The JSONL serializer uses `\n` as the record separator, so the deserializer should split only on `\n` rather than using `splitlines()`.

A possible fix is:

{{{
stream_or_string = stream_or_string.split(""\n"")
}}}

This continues to support CRLF input because the resulting line retains a trailing `\r`, which is valid JSON whitespace.

I have added regression tests covering U+2028, U+2029, and U+0085 with both `str` and `bytes` input, as well as a test confirming that CRLF line endings continue to work.

The issue does not affect loading JSONL from a file object in the same way, since file iteration uses the actual newline delimiter. However, it affects callers passing serialized JSONL as a string or bytes object to `serializers.deserialize()`.

I have reproduced the issue against Django's current development version."	Bug	assigned	Core (Serialization)	dev	Normal			Patel Namraa	Unreviewed	1	0	0	0	0	0