Element.prototype.role

[jonathantneal]

I’ve noticed that Element.prototype.role has an incomplete implementation in Safari.

document.createElement('button').role // null

Object.assign(document.createElement('button'), { role: 'button' }).role // "button"

I would have expected this reflection:

document.createElement('a').role // null
Object.assign(document.createElement('a'), { href: '' }).role // "link"

document.createElement('h1').role // "heading"
Object.assign(document.createElement('h1'), { role: 'button' }).role // "button"

Is there documentation or a proposal for this behavior specified somewhere?

Would this be part of ARIA, AOM, or something else?

[jnurthen]

@jonathantneal does https://wicg.github.io/aom/explainer.html#what-happened-to-accessiblenode help explain why this doesn't work today?

ARIA 1.2 only defines reflection of explicitly defined ARIA roles - it does not imply that implicit roles are exposed and indeed this is unlikely at this point in time. It sounds like you want https://wicg.github.io/aom/explainer.html#full-introspection-of-an-accessibility-tree---computedaccessiblenode which IMO is unlikely to ever be implemented outside of testing/developer tooling.

[jonathantneal]

The rationale in that document seems specific to one particular implementation that never shipped. Based on what ships in Safari, I would have expected role followed https://w3c.github.io/html-aam/.

I’m pretty unsure where my issue belongs. Still, Perhaps I can better organize my questions:

1. Where is or is there documentation for Element.prototype.role?
2. Is there interest in or would this be the place to discuss defining Element.prototype.role (as following html-aam), or actively discouraging its usage?

[cookiecrook]

@jonathantneal computedRole is being discussed as part of both WebDriver and AOM, but what you're requesting has some implementation blockers at the moment. In particular, role heuristics are usually only computed if AT needs it. Allowing web authors to trigger this on demand (by checking the computed role) has performance implications.

Closing, but reopen if you think this is worth continuing discuss within ARIA.