def _from_yaml_list()

in src/datasets/features/features.py [0:0]

• 56 lines of code
• 25 McCabe index (conditional complexity)

    def _from_yaml_list(cls, yaml_data: list) -> "Features":
        yaml_data = copy.deepcopy(yaml_data)

        # we convert the list obtained from YAML data into the dict representation that is used for JSON dump

        def unsimplify(feature: dict) -> dict:
            if not isinstance(feature, dict):
                raise TypeError(f"Expected a dict but got a {type(feature)}: {feature}")

            for list_type in ["large_list", "list", "sequence"]:
                #
                # list_type: int32          ->              list_type:
                #                           ->                dtype: int32
                #
                if isinstance(feature.get(list_type), str):
                    feature[list_type] = {"dtype": feature[list_type]}

            #
            # class_label:              ->              class_label:
            #   names:                  ->                names:
            #     '0': negative              ->               - negative
            #     '1': positive              ->               - positive
            #
            if isinstance(feature.get("class_label"), dict) and isinstance(feature["class_label"].get("names"), dict):
                label_ids = sorted(feature["class_label"]["names"], key=int)
                if label_ids and [int(label_id) for label_id in label_ids] != list(range(int(label_ids[-1]) + 1)):
                    raise ValueError(
                        f"ClassLabel expected a value for all label ids [0:{int(label_ids[-1]) + 1}] but some ids are missing."
                    )
                feature["class_label"]["names"] = [feature["class_label"]["names"][label_id] for label_id in label_ids]
            return feature

        def from_yaml_inner(obj: Union[dict, list]) -> Union[dict, list]:
            if isinstance(obj, dict):
                if not obj:
                    return {}
                _type = next(iter(obj))
                if _type == "large_list":
                    _feature = from_yaml_inner(unsimplify(obj).pop(_type))
                    return {"feature": _feature, **obj, "_type": "LargeList"}
                if _type == "sequence":  # backward compatibility
                    if isinstance(obj[_type], list):
                        _feature = from_yaml_inner(unsimplify(obj).pop(_type))
                        return {
                            name: {"feature": _subfeature, **obj, "_type": "List"}
                            for name, _subfeature in _feature.items()
                        }
                    else:
                        _feature = from_yaml_inner(unsimplify(obj).pop(_type))
                        return {"feature": _feature, **obj, "_type": "List"}
                if _type == "list":
                    _feature = from_yaml_inner(unsimplify(obj).pop(_type))
                    return {"feature": _feature, **obj, "_type": "List"}
                if _type == "struct":
                    return from_yaml_inner(obj["struct"])
                elif _type == "dtype":
                    if isinstance(obj["dtype"], str):
                        # e.g. int32, float64, string, audio, image
                        try:
                            Value(obj["dtype"])
                            return {**obj, "_type": "Value"}
                        except ValueError:
                            # e.g. Audio, Image, ArrayXD
                            return {"_type": snakecase_to_camelcase(obj["dtype"])}
                    else:
                        return from_yaml_inner(obj["dtype"])
                else:
                    return {"_type": snakecase_to_camelcase(_type), **unsimplify(obj)[_type]}
            elif isinstance(obj, list):
                names = [_feature.pop("name") for _feature in obj]
                return {name: from_yaml_inner(_feature) for name, _feature in zip(names, obj)}
            else:
                raise TypeError(f"Expected a dict or a list but got {type(obj)}: {obj}")

        return cls.from_dict(from_yaml_inner(yaml_data))