Create a use_linked_inputs widget instead of Input

[rmorshea]

Old Behavior

The current Input widget is clunky to use and was created primarily for the purpose of making it easier to construct a set of linked inputs. The current Input util also doesn't work when the IDOM_FEATURE_INDEX_AS_DEFAULT_KEY=1 feature flag is set.

New Behavior

To resolve this we should create a use_linked_inputs widget utility that can achieve this use case with a better interface and also work with the IDOM_FEATURE_INDEX_AS_DEFAULT_KEY=1 feature flag set.

Implementation Details

_CastInput = TypeVar("_CastInput")


def use_linked_inputs(
    attributes: Iterable[Dict[str, Any]],
    on_change: Callable[[_CastInput], None] = lambda value: None,
    cast: Callable[[str], _CastInput] = lambda value: value,
    initial_value: str = "",
    ignore_empty: bool = True,
) -> List[VdomDict]:
    """Return a list of linked inputs equal to the number of given attributes"""
    value, set_value = idom.hooks.use_state(initial_value)

    def sync_inputs(event: Dict[str, Any]) -> None:
        new_value = event["value"]
        set_value(new_value)
        if not new_value and ignore_empty:
            return None
        on_change(cast(new_value))

    return [
        idom.html.input({**attrs, "onChange": sync_inputs, "value": value})
        for attrs in attributes
    ]

[rmorshea]

Since index is now the default this needs to be fixed before the next release