ajaxError formats with line breaks, outputs as if HTML

I can confirm that Drupal.ajaxError() does use line breaks to format output and strips HTML output. The patch makes the error output readable.

Attached is the same patch but against D8.

Testbot was misbehaving ... it's been punished accordingly. Resetting test.

#2: wrap-error-output-in-pre-tags-898582.patch queued for re-testing.

I'm going to assume that the testbot was misbehaving again...

#2: wrap-error-output-in-pre-tags-898582.patch queued for re-testing.

Okay ... testbot beaten into submission. Tests passed.

Attached are two screenshots: one showing AJAX error output without the <pre> tags and one with the <pre> tags added.

Error needs to be replanned, see #1606362: Use throw when an ajax error occurs and extend JavaScript's Error object.

That said it's a welcome improvement. Needs reroll though.

(edit) oh and don't put the <pre> at this level, what we need it at the progress.js level, that's the only place we're adding the error output to the HTML.

Checking to see how to replicate the issue as this seems to be resolved in issue #2000558

In order to test this we did the following:

- Created a new module with an update hook that dies.
- Run update.php to apply the database updates.
- Checked that the returned error message is wrapped in pre tags.

Confirmed as no longer an issue. Closing issues

Thanks for checking!