Add new category for typeable form controls with normalization

[Holo-xy]

There looks to be a popular demand for normalized date and datetime-local as seen in 1470 and 42322342.
This introduces a new category to make the expected behavior explicit.

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[Holo-xy]

P.S. I wasn't sure if I should group the common logic of non-typable and typeable or not.

[OrKoN]

I think we should probably be more specific and define how exactly the input values should be normalized for date types. Also I wonder if it could be made optional because I imagine some existing clients would want to keep the current non-normalized behavior.

cc @whimboo @jgraham @sadym-chromium

[Holo-xy]

Right now the implementation accepts non-normalized values (MM-DD-YYYY format correctly), so we could keep the current implementation and just modify it to convert normalized values (YYYY-MM-DD or YYYYMMDD formats) to MM-DD-YYYY.
This way It would be techincally optional and require minmal implementation changes, but I'm not sure if this would be appropriate to add to the spec

[Holo-xy]

It would be something like this:

<p>
A <dfn>typeable form control with normalization</dfn>
is an [^input^] element
whose [^input/type^] attribute state
supports multiple input formats that should be converted to a consistent target format before being sent to the element.
This applies to <code>type="date"</code> and <code>type="datetime-local"</code> elements,
where both normalized (YYYY-MM-DD or YYYYMMDD) and traditional (MM-DD-YYYY) formats are accepted.

[OrKoN]

@sadym-chromium @whimboo @jgraham do you have a suggestion on how to best tackle input in the date fields? Should WebDriver require normalizing the input format?

[Holo-xy]

@sadym-chromium @whimboo @jgraham do you have a suggestion on how to best tackle input in the date fields? Should WebDriver require normalizing the input format?

Gentle Reminder.

[sadym-chromium]

Please define the "Normalize to the expected input format".

[sadym-chromium]

The approach LGTM, but the expected formats should be strictly defined.

[Holo-xy]

The approach LGTM, but the expected formats should be strictly defined.

I was thinking of doing something like this:

     <li><p>Normalize the <code>value</code> to conform to the expected input format of <var>element</var>.
      <ul>
        <li><p>For <code>type="date"</code> inputs, the <code>value</code> may be provided in <code>YYYY-MM-DD</code>, <code>YYYYMMDD</code>, or <code>MM-DD-YYYY</code> formats,
        and must be normalized to <code>MM-DD-YYYY</code>.
        <li><p>For <code>type="datetime-local"</code> inputs, the <code>value</code> may be provided in <code>YYYY-MM-DDTHH:MM:SS</code> or <code>MM-DD-YYYYTHH:MM:SS</code> formats,
        and must be normalized to <code>MM-DD-YYYYTHH:MM:SS</code>.
      </ul>
     <li><p><a>Set a property</a> <code>value</code> to <var>text</var>

I chose to normalize to MM-DD-YYYY and MM-DD-YYYYTHH:MM:SS since that seems to be what Chromium expects as input, which keeps changes minimal, but I'm not sure if this is the correct approach.

[whimboo]

I chose to normalize to MM-DD-YYYY and MM-DD-YYYYTHH:MM:SS since that seems to be what Chromium expects as input, which keeps changes minimal, but I'm not sure if this is the correct approach.

Does Chromium not support ISO 8601? I think that we should follow that format.

[Holo-xy]

I chose to normalize to MM-DD-YYYY and MM-DD-YYYYTHH:MM:SS since that seems to be what Chromium expects as input, which keeps changes minimal, but I'm not sure if this is the correct approach.

Does Chromium not support ISO 8601? I think that we should follow that format.

No, I tried inputting a date in ISO format, but the output was garbage (e.g. '2025-10-06' → '51006-02-02').

[OrKoN]

@whimboo I believe the accepted format is dependent on the user locale.

[OrKoN]

@Holo-xy I wonder if using locale overrides https://www.w3.org/TR/webdriver-bidi/#command-emulation-setLocaleOverride works around this issue? I imagine if you the locale is fixed, there could be no need for additional normalization?

[Holo-xy]

@whimboo I believe the accepted format is dependent on the user locale.

I don't think so, as I tested with different locales (US, UK, CH, which cover the three formats) and it didn't seem to make a difference.