As of Bug 1550801, they are functionally equivalent. So let's hg mv all the remaining xul files and update references to them.

As per https://bugzilla.mozilla.org/show_bug.cgi?id=1543834#c4, we can make sure intermittent bug tracking continues to work by renaming bug summaries to include the new file name in addition to the old one (https://bugzilla.mozilla.org/buglist.cgi?quicksearch=intermittent%20.xul&list_id=14887103)

After Bug 1581949, we have 88 remaining intermittent bugs with .xul in the name: https://mzl.la/2LVa6Al

Related list post about eslint getting enabled when filenames change from xul->xhtml https://groups.google.com/d/msg/firefox-dev/53dHw-tYYl0/b2YBKuMkAgAJ

Note to change line 1 in the script to fit the local mozilla-central repository.

(In reply to Brian Grinstead [:bgrins] from comment #0)

As per https://bugzilla.mozilla.org/show_bug.cgi?id=1543834#c4, we can make sure intermittent bug tracking continues to work by renaming bug summaries to include the new file name in addition to the old one (https://bugzilla.mozilla.org/buglist.cgi?quicksearch=intermittent%20.xul&list_id=14887103)

Following bugs have exceeded the maximum characters when trying to rename: Bug 890795, Bug 1006234, Bug 1571201, Bug 1389365, Bug 1235141.

(In reply to Emma Malysz from comment #6)

(In reply to Brian Grinstead [:bgrins] from comment #0)

As per https://bugzilla.mozilla.org/show_bug.cgi?id=1543834#c4, we can make sure intermittent bug tracking continues to work by renaming bug summaries to include the new file name in addition to the old one (https://bugzilla.mozilla.org/buglist.cgi?quicksearch=intermittent%20.xul&list_id=14887103)

Following bugs have exceeded the maximum characters when trying to rename: Bug 890795, Bug 1006234, Bug 1571201, Bug 1389365, Bug 1235141.

Wes, do you have an opinion on how to rename bugs to include the xhtml extension if they already hit the character limit? For example:

Intermittent TEST-UNEXPECTED-FAIL | /accessible/tests/mochitest/events/test_focus_autocomplete.xul | uncaught exception - NS_ERROR_ILLEGAL_VALUE: Component returned failure code: 0x80070057 (NS_ERROR_ILLEGAL_VALUE) [nsIAccessible.

Should we start taking characters out of the path, like:

Intermittent TEST-UNEXPECTED-FAIL | test_focus_autocomplete.xhtml,test_focus_autocomplete.xul | uncaught exception - NS_ERROR_ILLEGAL_VALUE: Component returned failure code: 0x80070057 (NS_ERROR_ILLEGAL_VALUE) [nsIAccessible.

Or take characters out of the message, like:

Intermittent TEST-UNEXPECTED-FAIL | /accessible/tests/mochitest/events/test_focus_autocomplete.xhtml,test_focus_autocomplete.xul | uncaught exception - NS_ERROR_ILLEGAL_VALUE: Component returned failure code: 0x80070057 (NS_

Or something else?

Treeherder technically only cares about the filename (for finding suggested bugs to recommend to the user; matching paths still get highlighted), not the path leading up to the filename. You can just drop the paths entirely unless they are actually relevant to the bugs filed about them.

For a bug to be listed as a suggestion, the bug summary must either contain an exact match from the failure line in the log as a substring, or the summary needs to contain a filename that treeherder has parsed out from the failure line (been a while since I looked at how it determines filename; think it takes the first piece before athe first | character, strips out TEST-UNEXPECTED-FOO, then looks for anything that looks like foo.bar)

Once the list of possible matches from thosechecks comes in to the UI, the possible matches are scored based on how much of the failure line matches up with the bug summary, and the bugs are sorted by their scores (so the more of the error message you can still fit in the summary, the higher scoring and sorted that bug will be if multiple bugs have beem filed for the same filename).

So to clarify: you should remove paths first, leaving only filenames and the error message. If there's still not enough room, you can drop parts or all of the error message.