Add machine_name setting type

I'm not against something like that but using the machine_name style it's not the right answer for ID attributes.

Technically, the value for an id attribute may contain any character, except whitespace characters. However, to avoid inadvertent errors, only ASCII letters, digits, '_', and '-' should be used, and the value for an id attribute should start with a letter.

https://developer.mozilla.org/en-US/docs/Web/HTML/Global_attributes/id

Even if it's okay to only have characters and underscores, hyphens are widely used and often preferred (especially in case the ID is used as an anchor). In fact, Google recommends to use hyphens and not underscores in URLs.
For IDs not used as anchor, we don't really have to care but we never know what these attributes are used for.

Side note: you might want to allow digits in your prop's pattern too ;)

So, according to proposal, instead of

it will be compliant with both https://www.drupal.org/node/2954832 → & https://developer.mozilla.org/en-US/docs/Web/HTML/Global_attributes/id

we can target:

it will be compliant with https://developer.mozilla.org/en-US/docs/Web/HTML/Global_attributes/id

I am OK with that too

MR done: https://git.drupalcode.org/project/ui_patterns_settings/-/merge_requests/17

With tests :)

Thanks!

Automatically closed - issue fixed for 2 weeks with no activity.