For attributes like Element.ariaControlsElements, which are a reflection
of FrozenArray<Element>, we must return the same JS::Array object every
time the attribute is invoked - until its contents have changed. This
patch implements caching of the reflected array in accordance with the
spec.
We are meant to store a weak reference to the element indicated by this
attribute, rather than a GC-protected strong reference. This also hoists
the "get the attr-associated element" AO into its own function, rather
than being hidden in IDL, to match "get the attr-associated elements".
There are ARIA attributes, e.g. ariaControlsElements, which refer to a
list of elements by their ID. For example:
<div aria-controls="item1 item2">
The div.ariaControlsElements attribute would be a list of elements whose
ID matches the values in the aria-controls attribute.
This change updates the contents of the AriaRoles.json file to match the
data in the Characteristics tables in the ARIA spec — at, for example,
https://w3c.github.io/aria/#application.
Most of the changes are to match the “Supported States and Properties”
and “Inherited States and Properties” data — but some changes are to
match the “Name From” data and “Accessible Name Required” data.
This change also intentionally removes all states and properties the
Characteristics tables list as “deprecated on this role in ARIA 1.2”.
This change causes explicit role=none and role=presentation attribute
values to be ignored in cases where the elements for which those values
are specified are either focusable, or have global ARIA attributes —
per https://w3c.github.io/aria/#conflict_resolution_presentation_none.
This change implements the role-checking requirement from the ARIA spec
at https://w3c.github.io/aria/#document-handling_author-errors_roles
that the “form” and “region” roles are required to have accessible
names — and that if they don’t have accessible names as required, UAs
must treat them as if they’d not been specified at all.
This change causes explicitly-specified role attributes to be ignored in
the case where the specified role is “orphaned” — that is, when its
element lacks a required ancestor with an appropriate role.
This change adds a virtual to_element function to ARIAMixin, and
overrides it in DOM::Element so it can then be used back inside
ARIAMixin to get an element when needed (for example, when computing a
role requires checking the roles of ancestors of an element).
This change does replacement of ARIA roles that have newer synonyms.
There are a number of newer ARIA roles that are synonyms for older
roles. https://wpt.fyi/results/wai-aria/role/synonym-roles.html has a
number of subtests which expect that when retrieving the value of an
explicitly- specified role attribute, if the value is one of the older
role values, implementations must replace that with its newer synonym.
Additionally: For “img” elements with empty “alt” attributes, change the
default role to the newer, preferred “none” synonym for the older
“presentation” role; import https://wpt.fyi/results/html-aam/roles.html
(which provides test/regression coverage for these changes).
This change separates the steps for checking the string value of the
ARIA “role” attribute out from the element.role_or_default() function
into a separate function — in order to expose a way to just check if the
ARIA “role” attribute actually has a value, without also then computing
a default role value if no “role” attribute value was found.
Otherwise, without this change, the only available function for
retrieving ARIA role values is the element.role_or_default() function —
which always does the additional step of computing (and returning) a
default role value if no “role” attribute is found.
We are currently constructing the attribute names as FlyStrings every
time we invoke one of the ARIA attributes getters/setters. If there are
not any other instances of these strings in-memory, then we're thrashing
the FlyString cache.
Instead, let's follow suit of all other Web attributes - use an x-macro
to generate the attribute names.
