Context/Scope of vars not working when schema/mixin imported from module

[diefans]

Bug Report

I am very confused, how the scope/context is applied resp. how _default_config is resolved.

My naive understanding was (before I moved the definitions to the module) that the scope/context is created at "init-time" and is somehow passed/"shining" from module level through the deeper schema tree... but now this issue confuses my a lot...

1. Minimal reproduce step (Required)

If I move schema/mixin/protocol definitions to a module a context var is not found: the working example is here

# INFO: this is in schemata.foo
protocol LoginProtocol:
    a_url: str
    b_url: str

mixin DefaultLoginMixin for LoginProtocol:
    # INFO: If no a_url, b_url is defined in the final schema, we apply the
    # value from _default_login
    a_url: str = a_url or _default_login.a_url
    b_url: str = b_url or _default_login.b_url

schema Config:
    mixin [
        DefaultLoginMixin
    ]

schema Stage:
    [...str]: Config
    _default_login: LoginProtocol

import schemata.foo

ci00 = foo.Stage {
    # FIXME: how is _default_login reaching the mixin, when defined in one script,
    # but not if the mixin is imported from a module?
    _default_login = foo.LoginProtocol {
        a_url = "https://default.a_url"
        b_url = "https://default.b_url"
    }
    provider_1 = foo.Config {}
    provider_2 = foo.Config {
        # INFO: override the default
        a_url = "https://custom.a_url"
        b_url = "https://custom.b_url"
    }
}

2. What did you expect to see? (Required)

ci00:
  provider_1:
    a_url: https://default.a_url
    b_url: https://default.b_url
  provider_2:
    a_url: https://custom.a_url
    b_url: https://custom.b_url

3. What did you see instead (Required)

EvaluationError
 --> /home/olli/code/bm/integration-config/schemata/foo.k:8:1
  |
8 |     a_url: str = a_url or _default_login.a_url
  |  invalid value 'UndefinedType' to load attribute 'a_url'
  |

4. What is your KCL components version? (Required)

❯ kcl --version
kcl version v0.10.8

[diefans]

Even if I define the Config schema in the same module, as where _default_config is created/instantiated/scoped, it still does not work. So this seems to defy the meaning of "mixin"...

import schemata.foo

schema Config:
    # FIXME: seems like resolution of _default_login is just looking into,
    # where the mixin is defined and not where it is applied/used/mixed-in
    mixin [
        foo.DefaultLoginMixin
    ]

schema Stage:
    [...str]: Config
    _default_login: foo.LoginProtocol

ci00 = Stage {
    # FIXME: how is _default_login reaching the mixin, when defined in one script,
    # but not if the mixin is imported from a module?
    _default_login = foo.LoginProtocol {
        a_url = "https://default.a_url"
        b_url = "https://default.b_url"
    }
    provider_1 = Config {}
    provider_2 = Config {
        # INFO: override the default
        a_url = "https://custom.a_url"
        b_url = "https://custom.b_url"
    }
}

[diefans]

@Peefy can you confirm, that my observation makes sense to you...? I also tried to find the place in the code, where I can start to fix it by myself... (resolving this would greatly improve our kcl code)

[Peefy]

cc @zong-zhe @He1pa