[webkit-changes] [WebKit/WebKit] 1a8243: AX: Grids/tables are not resilient to invalid Row-...

[Joshua Hoffman]

  Branch: refs/heads/main
  Home:   https://github.com/WebKit/WebKit
  Commit: 1a8243f4e81e0c14d5d032cf42037eafea856b67
      https://github.com/WebKit/WebKit/commit/1a8243f4e81e0c14d5d032cf42037eafea856b67
  Author: Joshua Hoffman <jhoffman23 at apple.com>
  Date:   2023-12-21 (Thu, 21 Dec 2023)

  Changed paths:
    A LayoutTests/accessibility/grid-row-authoring-error-ignored.html
    A LayoutTests/platform/glib/accessibility/grid-row-authoring-error-ignored-expected.txt
    A LayoutTests/platform/mac/accessibility/grid-row-authoring-error-ignored-expected.txt
    M Source/WebCore/accessibility/AXCoreObject.h
    M Source/WebCore/accessibility/AccessibilityObject.cpp
    M Source/WebCore/accessibility/AccessibilityObject.h
    M Source/WebCore/accessibility/AccessibilityRenderObject.cpp

  Log Message:
  -----------
  AX: Grids/tables are not resilient to invalid Row->Cell hierarchy
https://bugs.webkit.org/show_bug.cgi?id=266680
rdar://118938262

Reviewed by Chris Fleizach.

Our AX tree structure for tables is not resilient for a common authoring error where
table rows are not the direct unignored parent of table cells. This markdown does
not follow the spec (https://www.w3.org/TR/wai-aria-1.1/#gridcell), but is used
by authors regardless. This has shown be the cause of missing content in a variety
of tables.

To be more resilient to these errors, this patch makes all objects that are between
cells and their parent rows ignored. A new test was added to verify this behavior.

* LayoutTests/accessibility/grid-row-authoring-error-ignored.html: Added.
* LayoutTests/platform/glib/accessibility/grid-row-authoring-error-ignored-expected.txt: Added.
* LayoutTests/platform/mac/accessibility/grid-row-authoring-error-ignored-expected.txt: Added.
* Source/WebCore/accessibility/AXCoreObject.h:
* Source/WebCore/accessibility/AccessibilityObject.cpp:
(WebCore::AccessibilityObject::computeAncestorFlags const):
(WebCore::AccessibilityObject::matchesAncestorFlag const):
(WebCore::AccessibilityObject::isInRow const):
(WebCore::AccessibilityObject::ignoredByRowAncestor const):
* Source/WebCore/accessibility/AccessibilityObject.h:
* Source/WebCore/accessibility/AccessibilityRenderObject.cpp:
(WebCore::AccessibilityRenderObject::computeAccessibilityIsIgnored const):

Canonical link: https://commits.webkit.org/272447@main