Re: [PATCH] notmuch: Configure mailing list archive links

[Kyle Meyer <kyle@kyleam.com>]

Xinglu Chen writes:

> This adds an entry to `notmuch-show-stash-ml-archive-link-alist` that
> reads the `piem-inboxes` variable and returns the public-inbox archive
> url.  This means that users don't have to manually add public-inbox
> archive urls to `notmuch-show-stash-ml-archive-link-alist`.

Nice idea.  I regularly use notmuch-show-stash-mlarchive-link with
public-inbox targets and will happily drop my manual entries :)

I've considered something related in the past: adding a command in the
piem-dispatch transient that essentially does

  (when-let ((inbox (piem-inbox)))
    (kill-new
     (message
      "%s"
      (concat (piem--ensure-trailing-slash (piem-inbox-get :url inbox))
              (piem-escape-mid
               (or (piem-mid)
                   (user-error
                    "No message ID found for the current buffer")))))))

In notmuch, I'm already too accustomed to using
notmuch-show-stash-mlarchive-link (and more generally
notmuch-show-stash-map), but I think I'd occasionally find the above
useful in Gnus.  Hmm, perhaps I'll add such a command this weekend,
along with a section in the manual where we can mention it as well as
the notmuch-show-stash-mlarchive-link support added by this patch.

> diff --git a/piem-notmuch.el b/piem-notmuch.el
> index 5c0cd62..52d9198 100644
> --- a/piem-notmuch.el
> +++ b/piem-notmuch.el
> @@ -106,6 +106,13 @@ (defun piem-notmuch-am-ready-mbox ()
>                      (insert patch)))
>                  "mbox"))))))
>  
> +(defun piem-notmuch-show-get-public-inbox-link (mid)
> +  "Given the message-id MID, return the public-inbox url.
> +This will lookup the url in the `piem-inboxes' variable."
> +  (let* ((inbox (piem-inbox-by-header-match))
> +        (link (piem-inbox-get :url inbox)))
> +    (concat link mid)))

This will usually work, but

  * mid should be escaped with piem-escape-mid.

  * piem-inbox-by-header-match should be executed within
    piem-notmuch--with-current-message so that it can match against the
    full set of headers (which is important for matching the list ID).

    Better yet, just use piem-notmuch-get-inbox, which already does
    that.

  * What about in cases where there is no inbox/url?  Right now it would
    just return the plain message ID.  Should it signal a user-error
    instead?

> +
>  ;;;###autoload
>  (define-minor-mode piem-notmuch-mode
>    "Toggle Notmuch support for piem.
> @@ -119,11 +126,18 @@ (define-minor-mode piem-notmuch-mode
>          (add-hook 'piem-am-ready-mbox-functions #'piem-notmuch-am-ready-mbox)
>          (add-hook 'piem-get-inbox-functions #'piem-notmuch-get-inbox)
>          (add-hook 'piem-get-mid-functions #'piem-notmuch-get-mid)
> -        (add-hook 'piem-mid-to-thread-functions #'piem-notmuch-mid-to-thread))
> +        (add-hook 'piem-mid-to-thread-functions #'piem-notmuch-mid-to-thread)
> +        (add-to-list 'notmuch-show-stash-mlarchive-link-alist
> +                     '("piem" . piem-notmuch-show-get-public-inbox-link))
> +        (setq notmuch-show-stash-mlarchive-link-default "piem"))

I'd rather not override the user's
notmuch-show-stash-mlarchive-link-default setting (even if we were to
only do so for the default value of "Gmane", which we know is
nonfunctional and not likely coming back at this point).  Instead, how
about just mentioning notmuch-show-stash-mlarchive-link support in
piem-notmuch-mode's docstring along with a suggestion to set
notmuch-show-stash-mlarchive-link-default to "piem"?