Raise ValidationError from the config test validators - #1456
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`frequenz-quantities` 1.0.2 changed its `marshmallow` optional dependency floor from `< 4` to `>= 4` (frequenz-floss/frequenz-quantities-python#107), correcting metadata that had been wrong since that library was ported to `marshmallow` 4. That cap was the only thing holding us on `marshmallow` 3, as our own requirement has allowed `< 5` since 870e880, so CI now resolves `marshmallow` 4. `marshmallow` 4 removed support for validators that signal failure by returning `False`, deprecated in 3.24.0: Custom validators must raise a `ValidationError` for invalid values (deprecated in 3.24.0). Returning `False` is no longer supported. The configuration test dataclasses used exactly that pattern, a `lambda s: s.startswith("test")` in the field metadata. The validator is still registered and still called, only its return value is ignored, so the invalid value is accepted and `test_load_config_dataclass` and `test_new_receiver_configurations[Validation Error]` fail. Replacing the lambdas with a function that raises restores the checks. The message stays `Invalid value.`, which is what `marshmallow` 3 emitted through its `validator_failed` error key, so the expected output in `test_manager.py` is unchanged and the surrounding test cases remain consistent in asserting on `marshmallow`'s stock messages. Nothing under `src/` needed changing: the validators there are `marshmallow.validate.Range` and `OneOf`, which already raise. A raising validator also works on `marshmallow` 3, so the supported range is not narrowed, but the same silent acceptance can hit users who wrote their own boolean validators, hence the release notes entry. Signed-off-by: Leandro Lucarella <luca-frequenz@llucax.com>
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September 8, 2026 11:49
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quantities 1.0.3 is out, this is now green. I think we should release this as a "major release", as this breaking change will drag anyone using config schemas too. |
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CI started failing on
v1.x.xyesterday with three unrelated-looking config test failures. They come from thefrequenz-quantities1.0.2 release, which raised itsmarshmallowfloor to 4 (frequenz-floss/frequenz-quantities-python#107) and thereby draggedmarshmallow4 into our environment for the first time. Marshmallow 4 dropped support for validators that returnFalseinstead of raising, which is what the config test dataclasses were doing, so the validation silently stopped happening.The fix is test-only, but there is a release notes entry because the same silent acceptance hits anyone who wrote boolean validators for their own config dataclasses.
Heads-up for whoever reviews: the docs job on this PR will stay red, for a second and unrelated problem from the same
frequenz-quantities1.0.2 release. That one is a docstring infrequenz-quantitiesusing a relative mkdocstrings cross-reference, which misresolves whenever it is rendered under a path other than the one it was written in, as happens here withBaseConfigSchemainheritingQuantitySchema.TYPE_MAPPING. It cannot be fixed on this side, only worked around by dropping documentation, and frequenz-floss/frequenz-quantities-python#170 already fixes it upstream. #1455 is blocked on the same thing.