On Thu, 13 Dec 2012, Austin Clements <amdragon at MIT.EDU> wrote:
> Quoth Mark Walters on Dec 08 at 8:48 am:
>> On Sun, 02 Dec 2012, Austin Clements <amdragon at MIT.EDU> wrote:
>> > We detect the special exit statuses and use these to produce specific
>> > diagnostic messages.
>> > ---
>> > emacs/notmuch-lib.el | 32 ++++++++++++++++++++++++++++++++
>> > emacs/notmuch.el | 17 +++++++++++++----
>> > 2 files changed, 45 insertions(+), 4 deletions(-)
>> >
>> > diff --git a/emacs/notmuch-lib.el b/emacs/notmuch-lib.el
>> > index 9402456..49b0da6 100644
>> > --- a/emacs/notmuch-lib.el
>> > +++ b/emacs/notmuch-lib.el
>> > @@ -325,6 +325,38 @@ string), a property list of face attributes, or a
>> > list of these."
>> > (put-text-property pos next 'face (cons face cur))
>> > (setq pos next)))))
>> >
>> > +(defun notmuch-pop-up-error (msg)
>> > + "Pop up an error buffer displaying MSG."
>> > +
>> > + (let ((buf (get-buffer-create "*Notmuch errors*")))
>> > + (with-current-buffer buf
>> > + (view-mode)
>> > + (let ((inhibit-read-only t))
>> > + (erase-buffer)
>> > + (insert msg)
>> > + (unless (bolp)
>> > + (insert "\n"))
>> > + (goto-char (point-min))))
>> > + (pop-to-buffer buf)))
>>
>> I am not sure about the erase-buffer in the above: do we definitely want
>> to remove all previous error information? For version mismatch possibly
>> we do but in patch 9 it is done for all show command-line error returns.
>
> Why wouldn't we want to use a cleared buffer in all cases?
> notmuch-pop-up-error is only ever used when a command terminates, so
> there's no danger of us clearing errors that the user hasn't seen yet.
Just to make sure I understand this: whenever an error occurs the error
popup appears so we see the message. Then the next error can safely
erase buffer before showing the new error message?
>> Incidentally why does show always pop-up an error but search only for
>> version-mismatches?
>
> Historical reasons, I suppose. I was maintaining the status quo for
> search (which already had *some* error handling), but there was no
> error-handling status quo for show. Probably search should be more
> vocal when the command fails.
Should notmuch-call-notmuch-process also be switched to this framework?
In particular that also puts errors in "*Notmuch errors*" so my earlier
concern may be valid in this case.
Best wishes
Mark
>
>> Otherwise this looks good to me (but I am not that familiar with lisp
>> error handling)
>>
>> Best wishes
>>
>> Mark
>>
>>
>>
>>
>>
>>
>> > +(defun notmuch-version-mismatch-error (exit-status)
>> > + "Signal a schema version mismatch error.
>> > +
>> > +EXIT-STATUS must be the exit status of the notmuch CLI command,
>> > +and must have the value 20 or 21. This function will pop up an
>> > +error buffer with a descriptive message and signal an error."
>> > + (cond ((= exit-status 20)
>> > + (notmuch-pop-up-error "Error: Version mismatch.
>> > +Emacs requested an older output format than supported by the notmuch CLI.
>> > +You may need to restart Emacs or upgrade your notmuch Emacs package."))
>> > + ((= exit-status 21)
>> > + (notmuch-pop-up-error "Error: Version mismatch.
>> > +Emacs requested a newer output format than supported by the notmuch CLI.
>> > +You may need to restart Emacs or upgrade your notmuch package."))
>> > + (t
>> > + (error "Bad exit status %d" exit-status)))
>> > + (error "notmuch CLI version mismatch"))
>> > +
>> > ;; Compatibility functions for versions of emacs before emacs 23.
>> > ;;
>> > ;; Both functions here were copied from emacs 23 with the following
>> > copyright:
>> > diff --git a/emacs/notmuch.el b/emacs/notmuch.el
>> > index f9454d8..e1f28ca 100644
>> > --- a/emacs/notmuch.el
>> > +++ b/emacs/notmuch.el
>> > @@ -644,6 +644,7 @@ of the result."
>> > (exit-status (process-exit-status proc))
>> > (never-found-target-thread nil))
>> > (when (memq status '(exit signal))
>> > + (catch 'return
>> > (kill-buffer (process-get proc 'parse-buf))
>> > (if (buffer-live-p buffer)
>> > (with-current-buffer buffer
>> > @@ -655,8 +656,16 @@ of the result."
>> > (insert "Incomplete search results (search process was
>> > killed).\n"))
>> > (when (eq status 'exit)
>> > (insert "End of search results.")
>> > - (unless (= exit-status 0)
>> > - (insert (format " (process returned %d)" exit-status)))
>> > + (cond ((or (= exit-status 20) (= exit-status 21))
>> > + (kill-buffer)
>> > + (condition-case err
>> > + (notmuch-version-mismatch-error exit-status)
>> > + ;; Strange things happen when you signal
>> > + ;; an error from a sentinel.
>> > + (error (throw 'return nil))))
>> > + ((/= exit-status 0)
>> > + (insert (format " (process returned %d)"
>> > + exit-status))))
>> > (insert "\n")
>> > (if (and atbob
>> > (not (string= notmuch-search-target-thread
>> > "found")))
>> > @@ -664,7 +673,7 @@ of the result."
>> > (when (and never-found-target-thread
>> > notmuch-search-target-line)
>> > (goto-char (point-min))
>> > - (forward-line (1- notmuch-search-target-line))))))))
>> > + (forward-line (1- notmuch-search-target-line)))))))))
>> >
>> > (defcustom notmuch-search-line-faces '(("unread" :weight bold)
>> > ("flagged" :foreground "blue"))
>> > @@ -938,7 +947,7 @@ Other optional parameters are used as follows:
>> > (let ((proc (start-process
>> > "notmuch-search" buffer
>> > notmuch-command "search"
>> > - "--format=json"
>> > + "--format=json" "--use-schema=1"
>> > (if oldest-first
>> > "--sort=oldest-first"
>> > "--sort=newest-first")
>> >
>> > _______________________________________________
>> > notmuch mailing list
>> > notmuch at notmuchmail.org
>> > http://notmuchmail.org/mailman/listinfo/notmuch
>
> --
> Austin Clements MIT/'06/PhD/CSAIL
> amdragon at mit.edu http://web.mit.edu/amdragon
> Somewhere in the dream we call reality you will find me,
> searching for the reality we call dreams.
