mirror of
https://github.com/unslothai/unsloth.git
synced 2026-08-24 00:04:14 +00:00
44f113cf0d
* Escape the system message spliced into predefined chat templates
get_chat_template(..., system_message = ...) substitutes the message into a
{system_message} placeholder that sits inside a Jinja string literal in all 15
predefined templates that carry one, so a quote closes the literal and a
backslash is read as an escape:
vicuna "Answer the user's question." -> TemplateSyntaxError
vicuna r"Put it in \boxed{}." -> renders '\x08oxed{}'
vicuna r"C:\Users\me" -> TemplateSyntaxError
Reuse the escaper PR #7731 added for construct_chat_template, promoted to a
module-level _escape_jinja_literal and extended to escape double quotes so the
one helper covers llama-3.1's "..." literal as well as the '...' the rest use.
Apply it to the predefined branch of _change_system_message and to the ShareGPT
mapping values, and drop the hand-escaping from the two vicuna defaults, which
would otherwise be escaped twice.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
for more information, see https://pre-commit.ci
* Tighten the escaping comments
---------
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
82 lines
3.2 KiB
Python
82 lines
3.2 KiB
Python
import ast
|
|
import re
|
|
import types
|
|
from pathlib import Path
|
|
|
|
import pytest
|
|
|
|
|
|
def _load_change_system_message():
|
|
# Extract _change_system_message without importing unsloth (needs unsloth_zoo / a GPU).
|
|
source = Path(__file__).parents[2] / "unsloth" / "chat_templates.py"
|
|
tree = ast.parse(source.read_text(encoding = "utf-8"))
|
|
funcs = [
|
|
node
|
|
for node in tree.body
|
|
if isinstance(node, ast.FunctionDef)
|
|
and node.name in ("_change_system_message", "_escape_jinja_literal")
|
|
]
|
|
namespace = {
|
|
"re": re,
|
|
"logger": types.SimpleNamespace(warning_once = lambda *a, **k: None),
|
|
"DEFAULT_SYSTEM_MESSAGE": {"unsloth": "You are a helpful assistant to the user"},
|
|
}
|
|
module = ast.Module(body = funcs, type_ignores = [])
|
|
ast.fix_missing_locations(module)
|
|
exec(compile(module, str(source), "exec"), namespace)
|
|
return namespace["_change_system_message"]
|
|
|
|
|
|
CUSTOM = "mycustom" # no predefined default
|
|
|
|
|
|
def test_custom_template_fills_placeholder():
|
|
# A {system_message} placeholder must be filled, not left literal.
|
|
fn = _load_change_system_message()
|
|
template, used = fn("System: {system_message}\nUser:", CUSTOM, "You are a pirate")
|
|
assert template == "System: You are a pirate\nUser:"
|
|
assert "{system_message}" not in template
|
|
assert used == "You are a pirate"
|
|
|
|
|
|
def test_custom_template_preserves_backslashes():
|
|
# str.replace not re.sub: re.sub treats backslashes specially (r"C:\Users"
|
|
# bad-escape, r"\1" group ref), so messages must be inserted verbatim.
|
|
fn = _load_change_system_message()
|
|
for msg in (r"C:\Users\me", r"\frac{a}{b}", r"see \1 here"):
|
|
template, used = fn("System: {system_message}", CUSTOM, msg)
|
|
assert template == f"System: {msg}"
|
|
assert used == msg
|
|
|
|
|
|
def test_custom_template_requires_system_message():
|
|
# A placeholder with no system message must raise, not stay literal.
|
|
fn = _load_change_system_message()
|
|
with pytest.raises(ValueError):
|
|
fn("System: {system_message}", CUSTOM, None)
|
|
|
|
|
|
def test_custom_template_without_placeholder_unchanged():
|
|
fn = _load_change_system_message()
|
|
template, used = fn("System: fixed", CUSTOM, "ignored")
|
|
assert template == "System: fixed"
|
|
|
|
|
|
def test_predefined_template_uses_default_then_override():
|
|
fn = _load_change_system_message()
|
|
t1, u1 = fn("System: {system_message}", "unsloth", None)
|
|
assert t1 == "System: You are a helpful assistant to the user"
|
|
t2, u2 = fn("System: {system_message}", "unsloth", "Custom override")
|
|
assert t2 == "System: Custom override"
|
|
assert u2 == "Custom override"
|
|
|
|
|
|
def test_predefined_template_escapes_but_custom_does_not():
|
|
# Predefined templates hold {system_message} inside a Jinja literal, so it is escaped;
|
|
# a custom template's placeholder may be raw text, so it stays verbatim.
|
|
fn = _load_change_system_message()
|
|
msg = """it's a \\test "x"."""
|
|
predefined, used = fn("System: {system_message}", "unsloth", msg)
|
|
assert predefined == """System: it\\'s a \\\\test \\"x\\"."""
|
|
assert used == msg # returned message is the raw one, not the escaped source
|
|
assert fn("System: {system_message}", CUSTOM, msg)[0] == f"System: {msg}"
|