DX object to manage htmx headers

All tests green

We agreed in Slack to pause on this builder while we work on 📌 Refactor BigPipe to use HTMX Active using headers that are "hand-rolled."

Returning to this - we aren't using any headers in 📌 Refactor BigPipe to use HTMX Active

Took a quick pass and I need to do some research, but had a couple of high level questions.

1. Is there a way to make the triggerJson method return a more dynamic message to ensure something didn't blow up so bad that nothing is happening? So per step?
2. I didn't see the merging explicitly tested, do we need to chain them? or did I just miss that?

Improved \Drupal\KernelTests\Core\Http\HtmxHeaderTest::testJsonTriggers and added \Drupal\KernelTests\Core\Http\HtmxHeaderTest::testMerge

The Needs Review Queue Bot → tested this issue. It fails the Drupal core commit checks. Therefore, this issue status is now "Needs work".

This does not mean that the patch necessarily needs to be re-rolled or the MR rebased. Read the Issue Summary, the issue tags and the latest discussion here to determine what needs to be done.

Consult the Drupal Contributor Guide → to find step-by-step guides for working with issues.

All tests passing again

Ok I went through this very carefully.

I read the linked docs and confirmed they all link correctly.
I confirmed the parameters.
I confirmed all headers are accounted for.

I had some questions that would help me understand this better.
I have a couple of questions on process for parameter order.

I think there is one test with markup that needs updating.

I confirmed the test module calls each and all of my previous questions about gaps have been resolved.

I think this is pretty much ready once the questions are answered and that one test module string is reviewed.

Not sure if this requires a change record.

Questions answered and minor issues fixed :)

I think this is ready.

There are a couple of discussions open worth confirming that or conclusions are accurate.

This looks like a logical step most of my review notes are in 16.

Open process questions I have are, does this need a CR and did this need a subsystem maintainer review?

I've posted this in slack for confirmation but marking based on my reviews.

Noted in Slack that the object that is the main work of this issue is proposed to be composed into the object that is the main work of 📌 DX object to collect and manage HTMX behaviors Active which I think will be the most common context for interaction with the header object. I have the CR take on that issue so we can explain the whole picture.

Discussed and agreed in Slack that a single change record and release note will cover:

• 📌 DX object to manage htmx attributes Active
• 📌 DX object to manage htmx headers Active
• 📌 DX object to collect and manage HTMX behaviors Active
• 📌 Define and process an #htmx render array key Active