role=img should allow accName other than aria-label or aria-labelledby

[mitchellevan]

Requested change:

I'm requesting role=img be edited to use @mcking65's phrase from pull request #785 comments: authors MUST provide a label, which can be done with the aria-label or aria-labelledby attribute

This was in response to @carmacleod's draft in issue #783 comments: In order for elements with a role of img to be perceivable, authors MUST provide a label determined by the accessible name calculation.

Currently:

The ARIA spec for role=img currently says, "authors MUST provide a label using the aria-label or aria-labelledby attribute."

However, in some cases role=img can get its accessible name from a name from author mechanism, without actually using either aria-label or aria-labelledby. The ARIA spec should not prohibit these cases.

1. ARIA in HTML allows role=img on an <iframe> element, which can get its accessible name from a title attribute.
2. role=img is "NOT RECOMMENDED" for an <img> element, but a valid reason may exist to use it, such as @scottaohara's workaround for a Safari bug. In this case the alt attribute of an <img> can still provide its accessible name.

[JAWS-test]

role=img is allowed for other HTML elements that can be labeled with the title attribute. Furthermore, role=img is allowed on SVG graphics that can be labeled with the title element or per text content

[mitchellevan]

role=img is allowed for other HTML elements that can be labeled with the title attribute.

I agree. This is not a coding best practice, but it should not fail ARIA validation.

Furthermore, role=img is allowed on SVG graphics that can be labeled with the title element or per text content

When you say "labeled with," if you mean...

<svg role="img" aria-labelledby="svg-title">
    <title id="svg-title">HTML5 logo</title>...
</svg>

... then that's a true statement, but not relevant to this issue, because it already passes with or without my proposed edit.

If you mean without aria-labelledby, then that is not a true statement because role=img does not allow name from content (notwithstanding issue #1330).

[JAWS-test]

If you mean without aria-labelledby, then that is not a true statement because role=img does not allow name from content

Yes, I meant that. And the title element is not "name from content", but "name from author". I think that here the AccName specification is unclear if within role=presentation labeling with author elements like label, title, caption etc. should be possible or not

[mitchellevan]

You're right @JAWS-test, my mistake. A <title> does name <svg role="img">. Thanks for adding these examples, which support the value of my proposed edit.