SIA-R83Text nodes are not clipped when text is resized

Accessibility requirements

This rule tests conformance of the following accessibility requirements:

This rule checks that text nodes are not unintentionally clipped by overflow when the text is resized.

This rule applies to every text node for which all of the following is true:

The text node is visible; and
The text node has an element in the HTML namespace as a parent in the flat tree; and
The text node has an ancestor in the flat tree with a computed overflow-x or overflow-y of hidden or clip; and
The text node does not have an ancestor in the flat tree with an aria-hidden attribute with a value of true.

Each test target is not clipped by overflow of an ancestor in the flat tree, except if the clipping ancestor has one of the following:

text-overflow: A computed white-space of nowrap, and a computed text-overflow that is not clip; or
line wrapping: A computed line-height equal to or greater than the height of its bounding box, or in case of a computed overflow of clip, its content box.

If any of the following assumptions is true, failing this rule may not result in a failure of success criterion 1.4.4 Resize text:

There is no other mechanism for resizing text available on the page, that can be used to resize text to 200% without loss of information or functionality. This includes font resizing in the browser, or a JavaScript mechanism of resizing in the page.
Text nodes can not be clipped by overflow without loss of information, except for text nodes with an ancestor with aria-hidden set to true, or when specific styles have been applied to ensure text is clipped cleanly (text-overflow, line wrapping or hidden text).

This rule has no accessibility support concerns.