Re: font-lock-add-keywords in hi-lock.el

[Bill Wohler]

Stefan Monnier <address@hidden> writes:

>>>> Is that enough information to find the culprit, or is there a watch I
>>>> can put on the global value of font-lock-keywords which will print a
>>>> stacktrace or enter the debugger when it is changed?
>>> ...
>>> 
>>> Before fixing it, it would be useful to know how it gets called.
>>> In the buffer list you sent earlier there is the *Occur* buffer.
>>> Do you remember on what buffer you called `occur'?  Very likely
>>> `occur' forced fontification on a non-font-lock buffer.
>
> I've added a sanity check in font-lock-compile-keywords which should at
> least catch the offenders before they wreak havoc (hopefully the offenders
> are not font-lock itself).

Thanks. I'll have to try that.

In the meantime, I can now reproduce the problem! And, it's uh, in
MH-E :-(.

  emacs -Q
  C-x b foo RET
  M-: font-lock-keywords RET
  => nil
  C-x k RET
  M-x mh-rmail
  C-x b foo RET
  M-: font-lock-keywords RET
  => (t nil)                  (but only if you have unseen messages in +inbox)
  C-x k RET
  F v +some-folder RET        (mh-visit-folder, must have at least one message)
  C-x b foo RET
  M-: font-lock-keywords RET
  => (t nil)

Interestingly, I found that if you kill a folder's buffer and then
revisit that folder, this problem does not reappear. But choose a
folder that you haven't yet visited with at least one message, and it
does.

Can you guys take a quick peek and see if you see anything obvious? If
not, I'll debug this.

If you have GNU mailutils or nmh installed, and you can get a message
in +some-folder you should be able to perform the above steps. (Hint:
the first chapter of the MH-E manual--even the old one that is
currently in Emacs--is a tutorial which will help you do this.)

I've opened an MH-E bug #1393879 on this:

https://sourceforge.net/tracker/index.php?func=detail&aid=1393879&group_id=13357&atid=113357

-- 
Bill Wohler <address@hidden>  http://www.newt.com/wohler/  GnuPG ID:610BD9AD
Maintainer of comp.mail.mh FAQ and MH-E. Vote Libertarian!
If you're passed on the right, you're in the wrong lane.