The ARIA roles model requires that elements with a role attribute use a valid, non-abstract ARIA role. Each non-abstract ARIA role is mapped on to a known set of behavior by the user agent or assistive technology, so using an unknown role will result in the desired behavior not being available to the user.
You can find a list of valid ARIA roles, along with descriptions and information on additional required attributes, on the WAI-ARIA site.
This rule takes no options
// passes when there is a role and it is valid
<div role="button"></div>
// passes when there is no `role`
<div></div>// fails when there is an invalid `role`
<div role="foo"></div>- This document from w3.org - Google Audit defs AX_ARIA_01