Dirname should work with more input types

[r12a]

I'm wondering why tel and hidden types are excluded from working with dirname.

I'm inclined to think that it would be particularly useful to pass on information that a telephone number should be stored or handled as a LTR sequence so that it can be correctly rendered elsewhere – telephone numbers are one of the key areas where users struggle with bidi rendering, because they typically only include weak directional characters.

I could also imagine text being passed to a database via a hidden input element that may be directionally-sensitive, in which case dirname may be useful.

This may also apply to email and url types. If a person's email address is mostly in Arabic (پبتث@شجغ.sa), it may be good to store metadata about the direction set by the user when typing in the address, so that it can be rendered right to left in another location. Such an address will look very different in a LTR context.

A field set to RTL by the user while typing their email address:

The same email address retrieved from a database and rendered without correction of the base direction in a LTR page:

[annevk]

cc @whatwg/forms

[zcorpan]

https://html.spec.whatwg.org/#bidi-rendering says

Input fields (i.e. textarea elements, and input elements when their type attribute is in the Text, Search, Telephone, URL, or Email state) are expected to present an editing user interface with a directionality that matches the element's 'direction' property.

While this doesn't say that users are expected to be able to change the directionality for these elements, it seems inconsistent to support author-provided directionality but only allow users to change directionality for a subset, or to allow changing directionality but then not submitting it with dirname.

hidden may be useful as a way of submitting contenteditable elements.

Relatedly, https://html.spec.whatwg.org/#persisted-user-state-restoration also says to (optionally) restore dir attribute values in session restore:

Optionally, update other aspects of entry's document and its rendering, for instance values of form fields, that the user agent had previously recorded in entry's persisted user state.

Note: This can even include updating the dir attribute of textarea elements or input elements whose type attribute is in either the Text state or the Search state, if the persisted state includes the directionality of user input in such controls.

This note should probably be updated if we allow dirname on more elements.

[zcorpan]

PR at #9490

Is there interest from WebKit and Chromium?

[annevk]

Yeah this seems reasonable.

[r12a]

Many thanks!