Unable to save Config or convert to str if header ends with *

[HLasse]

When using variadic arguments in the ending of headers in a config, the Config can not be saved.

Minimal example:

import catalogue
from confection import Config, registry


class Registry(registry):
    registry = catalogue.create("psycop", "test_reg")


@Registry.registry.register("test_fn")
def test_fn(*args: str):
    return(args)


config_str = """
[test_fn]
@registry = "test_fn"

[test_fn.*]
arg1 = "test1"
arg2 = "test2"
"""

if __name__ == "__main__":
    cfg = Config().from_str(text=config_str)
    resolved = Registry.resolve(cfg)
    print(resolved["test_fn"])
    cfg.to_str()

Output

('test1', 'test2')
Traceback (most recent call last):
  File "/workspaces/psycop-common/confection_test.py", line 27, in <module>
    cfg.to_str()
  File "/usr/local/lib/python3.10/site-packages/confection/__init__.py", line 447, in to_str
    flattened.set(section_name, key, try_dump_json(value, node))
  File "/usr/local/lib/python3.10/configparser.py", line 1206, in set
    super().set(section, option, value)
  File "/usr/local/lib/python3.10/configparser.py", line 904, in set
    raise NoSectionError(section) from None
configparser.NoSectionError: No section: 'test_fn.*'

The config is resolved correctly, but we encounter a NoSectionError when attempting to output the config to a str.

Workaround
Specifying the variadic arguments under the test_fn header makes it both resolve and output as str correctly, but might not to viable in all cases if the input is of a more complex type.

config_str = """
[test_fn]
@registry = "test_fn"
* = ["test1", "test2"]
"""

Is this something you'd want to support?

[svlandeg]

Merging with #52

[HLasse]

Whoops, my bad - I had forgotten everything about the other issue 😶‍🌫️