[faciledictu]

Summary:

Fixes #59816.

ViewShadowNode::initialize keeps a host view for only a few accessibility props (accessible, accessibilityViewIsModal, accessibilityLiveRegion and three more). iOS and Android also read several others from a view that is not an accessibility element, and they are lost when the view is flattened:

• accessibilityLabel: TalkBack reads it from the container; an accessible ancestor builds its label from its subviews.
• accessibilityRole / role and accessibilityState: the TabBar trait on iOS; heading, checkable and the state on Android.
• accessibilityActions, onAccessibilityEscape, onAccessibilityMagicTap: iOS passes them to the elements inside or sends them up the hierarchy.
• accessibilityShowsLargeContentViewer, accessibilityIgnoresInvertColors: they apply to the subviews on iOS.

This change keeps the view when any of them is set, as #59335 did for accessibilityLiveRegion. The old architecture kept these views too.

Left out on purpose: accessibilityHint, accessibilityLanguage and accessibilityValue, which are not read from a container, and aria-busy / aria-checked="mixed": on Android they go into contentDescription and replace the children's text (a separate bug), so a kept view would be read as "busy".

Changelog:

[GENERAL] [FIXED] - A View with accessibilityLabel, role, accessibilityState, accessibilityActions, onAccessibilityEscape or another accessibility prop read from a container is no longer flattened

Test Plan:

• Fantom (View-itest.js): the does not unflatten view tests for accessibilityLabel, accessibilityRole and accessibilityActions asserted the bug and are now unflattens view (the accessibilityActions one also checked the wrong prop). Added: role and aria-checked unflatten, aria-busy and aria-checked="mixed" do not. The iOS-only props are not in the view config Fantom uses. The rest of the suite passes, except 9 LogBoxInspector* snapshot tests that fail the same way on main (93019c4).
• On devices, with https://github.com/faciledictu/rn-a11y-flattening-repro and 0.88.0 built from source with this change backported, each flattened View now matches its collapsable={false} control (the results without the change are in Fabric flattens a View whose accessibility props iOS and Android read from a container: label, role, state, actions, escape #59816):
  • Android, the accessibility nodes on a device: sections 1, 2, 3, 6, 7, 8 and 13.
  • iOS simulator, Accessibility Inspector: sections 2, 3, 4, 5, 6 and 10 (the label "Close dialog P1" instead of "× P1", the Archive action, the Large Content Viewer, Smart Invert).
  • iPhone, VoiceOver: the tab is read as "Tab K1, tab, 1 of 2", and escape runs its own wrapper's handler, not the other dialog's.

[javache]

Can you add a helper on AccessibilityState instead? eg isMeaningful?

[faciledictu]

Done, added AccessibilityState::isMeaningful(). It leaves out busy and mixed on purpose: on Android they go into the content description and replace the children's text (#59856).

[javache]

Do these require a stacking context (parent-child structure is retained, or would formsView be sufficient`?

[faciledictu]

They need the children inside. With formsView alone (I checked with a backgroundColor on the same views) the view is kept but its children are mounted next to it, and each case behaves as if it were flattened: the label inside a Pressable reads "Close dialog, ×", the tabbar and the parent's actions don't reach the tabs and the child, and on Android the labelled view is an empty node next to the text. Section 14 in https://github.com/faciledictu/rn-a11y-flattening-repro.