Fix BottomSheetBackdrop "falsey" defaults

[thecodedrift]

This is a change to how BottomSheetBackdrop handles its falsey defaults. Values such as 0 and false will automatically assume their fallback values instead of allowing their literal 0 or false to be applied. There is a reproducible Snak in #779 which shows the problem.

https://snack.expo.dev/@jakobo/bottomsheetbackdrop---appearsonindex-bug

Motivation

The fix is to ensure that the provided value was truly undefined before assigning the default. This patch uses nullish coalesce ?? to achieve that. The following code will never render a backdrop.

const renderBackdrop = useCallback(
  props => (
    <BottomSheetBackdrop
      {...props}
      disappearsOnIndex={-1}
      appearsOnIndex={0}
    />
  ),
  []
);

Under the hood, BottomSheetBackdrop will assign 1 for appearsOnIndex because JS treats 0 as false-like.

Contributing Guidelines ✅

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  • note There were additional unrelated prettier errors which were fixed in the second commit
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[github-actions]

This PR is stale because it has been open 30 days with no activity. Remove stale label or comment or this will be closed in 10 days.

[thecodedrift]

@gorhom, let me know if there's anything I can do to help get this PR approved. I'll continue to rebase as necessary since the changes are scoped to mostly the Backdrop component

[github-actions]

This PR is stale because it has been open 30 days with no activity. Remove stale label or comment or this will be closed in 10 days.

[thecodedrift]

Rebase verification (and un-stale): Current branch jakobo/779/BottomSheetBackdrop_defaults is up to date.

[IngyuTae]

Hi, @gorhom Do you have any plan on this PR?

[github-actions]

This PR is stale because it has been open 30 days with no activity. Remove stale label or comment or this will be closed in 10 days.

[thecodedrift]

@gorhom (ping) The fix is 3 Stalebots old. Would love to land this.

[gorhom]

hi @jakobo, thanks for submitting this PR, i left one comment regarding the name convention for the props.

[thecodedrift]

Applied the requested changes, @gorhom. Let me know if there's any other changes. 🎉

[gorhom]

thanks @jakobo for updating the naming! this will be release on the next patch release