[drawer] Respect canceled snap point dismissal

[radist2s]

Fixes #5570

With snapPoints, a swipe dismissal first proposes null through onSnapPointChange. Consumers can cancel this change, but closeFromSnapPoints currently continues into the swipe release even when the event details are canceled.

This temporarily applies the popup's exit state and can request onOpenChange(false). When a controlled consumer rejects that close as well, the popup fades out before being restored to its previous snap point.

Reproduction

Both examples use the same controlled Drawer scenario and the same Base UI preview packages. The fixed example applies this change through a Yarn patch.

• Before — reproduction
• After — fixed

Steps:

1. Wait for the Drawer to open at the collapsed snap point.
2. Quickly drag the handle downward past the lowest snap point and release.
3. Compare the popup behavior and the event log.

Before:

onSnapPointChange(null) canceled
onOpenChange(false) canceled
onSnapPointChange(0.26) accepted

The popup can briefly fade out before returning.

After:

onSnapPointChange(null) canceled

The canceled dismissal settles immediately without entering the exit state.

Changes

• Check snapPointEventDetails.isCanceled immediately after proposing the null snap point.

• Reset swipe progress and clear the release state when the proposal is canceled.

• Return before storing a pending close snap point or starting the swipe release.

• Add a regression test that verifies onOpenChange is not called and that neither data-ending-style nor data-swipe-dismiss is applied, including transient attribute changes.

• I have followed (at least) the PR section of the contributing guide.

[pkg-pr-new]

• base-ui-tanstack-start

• vite-css-base-ui-example

  pnpm add https://pkg.pr.new/mui/base-ui/@base-ui/react@5571
  

  pnpm add https://pkg.pr.new/mui/base-ui/@base-ui/utils@5571
  

commit: 656c799

[code-infra-dashboard]

Bundle size

Bundle	Parsed size	Gzip size
@base-ui/react	🔺+31B(+0.01%)	🔺+17B(+0.01%)

Details of bundle changes

Performance

Total duration: 1,194.87 ms -16.93 ms^(-1.4%) | Renders: 76 ⁽⁺⁰⁾ | Paint: 1,925.91 ms -57.76 ms^(-2.9%)

Test	Duration	Renders
Combobox type — 500 items, narrows to ~11 (type "Row 25")	38.74 ms ▼-11.76 ms(-23.3%)	15 (+0)

14 tests within noise — details

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[atomiks]

Thanks for the fix @radist2s

[radist2s]

@atomiks, thank you so much for your prompt response! You’re brilliant, guys!