List.AccordionGroup ignores a controlled expandedId of 0 #5144

Current behaviour

When List.AccordionGroup is controlled and expandedId is the number 0, no accordion expands. The accordion with id={0} stays collapsed, even though id={0} is supported since #3936.

ListAccordionGroup resolves the expanded ID with expandedIdProp || expandedId. Because 0 is falsy, the group falls back to its internal state, which is never updated in controlled mode.

Expected behaviour

The accordion whose id matches the controlled expandedId expands, including when the ID is 0.

How to reproduce?

const [expandedId, setExpandedId] = React.useState<number | string>(0);

<List.AccordionGroup expandedId={expandedId} onAccordionPress={setExpandedId}>
  {['First', 'Second'].map((title, index) => (
    <List.Accordion key={title} title={title} id={index}>
      <List.Item title={`${title} item`} />
    </List.Accordion>
  ))}
</List.AccordionGroup>

The first accordion (id={0}) is collapsed on mount, and pressing it never expands it. Pressing the second accordion works.

What have you tried so far?

Replacing expandedIdProp || expandedId with expandedIdProp ?? expandedId in src/components/List/ListAccordionGroup.tsx fixes it.

Your Environment