Hydra: multirun override for structured config parameter whose group is set by defaults does not work

[egonuel]

🐛 Bug

I have a few structured config classes, which I use mainly as verification schemes.
I define defaults for the corresponding groups in the main config.yaml
Now if I want to do a multi-run over a parameter from these groups, it crashes and it appears that hydra is unable to split the multiple values for that parameter.
The following small example shows that behavior. However, I found out that if I add the group to main config.yaml (the commented config lines below) then it works as expected.

To reproduce

conf/config.yaml:

defaults:
  - test: default

# test:
#   param: 0

conf/test/default.yaml:

# @package _group_
param: 10

test.py:

from dataclasses import dataclass

import hydra
from hydra.core.config_store import ConfigStore
from omegaconf import MISSING, DictConfig


@dataclass
class TestConfig:
    param: int = MISSING


config_store = ConfigStore.instance()
config_store.store(group="test", name="default", node=TestConfig)


@hydra.main(config_path="conf", config_name="config")
def run(config: DictConfig):
    print(config.pretty())


if __name__ == "__main__":
    run()

* Stack trace/error message *

test.py -m test.param=42,23 

Error merging override test.param=42,23
Value '42,23' could not be converted to Integer
        full_key: test.param
        reference_type=Optional[TestConfig]
        object_type=TestConfig

Expected Behavior

do multirun for values 42 and 23

System information

• Hydra Version : 1.0.0.rc1
• Python version : Python 3.8.3
• Virtual environment type and version : conda 4.8.3
• Operating system : ubuntu 18.04

Additional context

Add any other context about the problem here.

[omry]

Thanks for reporting, I will take a look.
in the mean time, can you:

1. try to repro without structured configs.
2. Test your minimal example from 1 on both 0.11 and 1.0?

[egonuel]

the answer for 1. I could have given in the first post, sorry: it does work when I do not store the corresponding structured config class.
I Will answer 2. later.

[egonuel]

ok, and the answer for 2. is obvious: it works as well.
So without structured configs the example both works on 0.11 and 1.0rc.

[egonuel]

it works, thanks a lot!

[omry]

awesome, thanks for for testing!