fix: accept empty str to str_to_raw_id() (#23)

Author: Chaoses-Ib

src/comfy_script/astutil.py

@@ -24,7 +24,8 @@ def is_xid_continue(s: str) -> bool:
 
 def str_to_raw_id(s: str) -> str:
     s = s.lstrip()
-    assert s != ''
+    if s == '':
+        return '_'
 
     if s.isascii():
         s = re.sub(r'[^A-Za-z_0-9]', '_', s)

tests/test_astutil.py

@@ -4,6 +4,7 @@
 import comfy_script.astutil as astutil
 
 @pytest.mark.parametrize('s, id', [
+    ('', '_'),
     (':<', '_'),
     (':|', '_'),
     (':/', '_'),