Enable a means of testing spelling errors and highlights

[bkardell]

Currently browsers have some downstream means of doing this, but we'd love to enable this to be testable via a web driver method like markSpellingError(Range) and be able to write web platform tests for this sort of thing.

[whimboo]

@bkardell I assume you are referring to the following specifications?

• https://html.spec.whatwg.org/multipage/interaction.html#spelling-and-grammar-checking
• https://www.w3.org/TR/selection-api/

Maybe you can give more details about how those APIs should work, and what the expectation / response should be. This would help us to get started a discussion. Maybe it would then be WebDriver BiDi only.

[bkardell]

Well, and CSS has pseudo selectors for these like ::spelling-error and ::grammar-error... I'll tag in @schenney for more...

[schenney-chromium]

The features we currently cannot reliably test are the CSS Highlight Pseudos that depend on UA generated markers, specifically ::spelling-error, ::grammar-error and ::search-text (though the latter is in some danger of being removed). Right now there is no way to add the ranges for these in WPT tests.

The content_shell test framework for Chromium exposes JS apis to set ranges for the specific marker types and this is the kind of functionality we would like to have in WPT.

::selection, ::target-text and ::highlight(...) can be tested in WPT because there are APIs for setting selection and custom highlight ranges, and ways to fool a browser into a navigation with target text.