Enable opting-out of form submissions

[seanpdoyle]

Similar to Disabling Turbo Drive on Specific Links,
guard intercepting form subissions with a similar check for
[data-turbo-drive="false"] on the submitter, <form> element, or an
ancestor.

Similarly, do not intercept when the submitter or form element
specifies a method that isn't an HTTP verb (via
formmethod="dialog" attribute or method="dialog"
attribute, respectively).

In practice, HTTP submitting <form> elements will only ever declare
method="get" or method="post". The one exceptional case is
method="dialog", which we check for as a special case.

Testing

Since we're covering behavior for the <dialog> element and running
the suite in both Chrome and Firefox, the test suite needs to polyfill
support for the <dialog> element.

[domchristie]

Would this be a good place to incorporate the changes from https://github.com/turbolinks/turbolinks/pull/495/files?

I've not manually tested Turbo Drive with non-fetch form submissions, but from the look of Session#start, the initial replace will still break the "Are you sure…?" refresh behaviour after rendering a form submission:

turbo/src/core/drive/history.ts

Line 35 in c52d87c

this.replace(Location.currentLocation)

After a traditional POST, calling history.replaceState will replace the POST entry with a GET, and therefore refreshing won't trigger the confirm dialog. The fix was to store the initial restoration identifier as a property on the History instance rather than replacing the browser's history state.

I'd be happy to port these changes over if there's interest?

[ChrisZou]

My I ask when would this be merged? 😂😂 Quite a few issues are depending on this to be fixed. It's preventing me to use hotwire to do so many things.

[jon-sully]

Just adding in case other folks come around, I believe contrary to the initial description of this PR, the necessary attribute on the <form> needs to be data-turbo="false", not data-turbo-drive="false"

But this is well-documented on https://turbo.hotwire.dev/handbook/drive#disabling-turbo-drive-on-specific-links-or-forms

In Rails parlance,

form_with model: @xyz, url: etc, data: { turbo: false }

Which is great because data: { 'turbo-drive' => false } doesn't look nearly as slick 😜