[PATCH 0/5] *** Resubmit: Warping via the registry ***

[PATCH 0/5] *** Resubmit: Warping via the registry ***

[Dave Abrahams]

Note: I submitted this patch series back in October
(http://permalink.gmane.org/gmane.emacs.gnus.general/80250).  It still
applies perfectly, but I rebased just in case.  I'd really appreciate
it if this series could get some attention.  Further explanation of
the motivation for this series is in
http://article.gmane.org/gmane.emacs.gnus.general/80277. Thanks!


This patch series implements the ability to warp to a message via
information stored in the Gnus registry.  From a user's point-of-view,
this means that articles brought in from other groups by
gnus-*-refer-* can be used as a jumping-off-point for further
references.  For example, I am using this code to jump to a given
message:

(defun gnus-goto-article (message-id)
  (with-temp-buffer
    (erase-buffer)
    ;; Insert dummy article
    (insert (format "From nobody Tue Sep 13 22:05:34 2011\n\n"))
    (gnus-group-read-ephemeral-group
     message-id
     `(nndoc ,message-id
             (nndoc-address ,(current-buffer))
             (nndoc-article-type mbox))
     :activate
     (cons (current-buffer) gnus-current-window-configuration)
     (not :request-only)
     '(-1) ; :select-articles
     (not :parameters)
     0     ; :number
     )
    (gnus-summary-refer-article message-id)
    ))

Before applying this patch series, I could not get to the whole thread
with `A T' because Gnus was unable to warp to the article in its
original group.

How it works
------------

Each time a message is fetched from a backend, its group is noted in
the registry.  Warping now consults the backend of the current group,
and if that fails, tries warping to the article in each group stored
for it in the registry until one succeeds.

Dave Abrahams (5):
  Allow gnus-summary-insert-subject to work in empty groups.
  Record information in the registry about each article retrieved
  Add `gnus-select-group-with-message-id'
  Add `gnus-try-warping-via-registry()'
  Enable registry-warping as a fallback if warping via the current
    backend fails.

 lisp/gnus-int.el |  101 ++++++++++++++++++++++++++++++++++++++++++++++++++++--
 lisp/gnus-sum.el |   11 +++++-
 2 files changed, 107 insertions(+), 5 deletions(-)

-- 
1.7.5.4

[PATCH 1/5] Allow gnus-summary-insert-subject to work in empty groups.

[Dave Abrahams]

In groups that haven't been populated yet, the minimum and maximum
article numbers are nil; that wasn't accounted for
---
 lisp/gnus-sum.el |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/lisp/gnus-sum.el b/lisp/gnus-sum.el
index 46e246f..8c7334a 100644
--- a/lisp/gnus-sum.el
+++ b/lisp/gnus-sum.el
@@ -6626,9 +6626,9 @@ too, instead of trying to fetch new headers."
       ;; article if ID is a number -- so that the next `P' or `N'
       ;; command will fetch the previous (or next) article even
       ;; if the one we tried to fetch this time has been canceled.
-      (when (> number gnus-newsgroup-end)
+      (unless (and gnus-newsgroup-end (< number gnus-newsgroup-end))
 	(setq gnus-newsgroup-end number))
-      (when (< number gnus-newsgroup-begin)
+      (unless (and gnus-newsgroup-begin (> number gnus-newsgroup-begin))
 	(setq gnus-newsgroup-begin number))
       (setq gnus-newsgroup-unselected
 	    (delq number gnus-newsgroup-unselected)))
-- 
1.7.5.4

[PATCH 2/5] Record information in the registry about each article retrieved

[Dave Abrahams]

---
 lisp/gnus-sum.el |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/lisp/gnus-sum.el b/lisp/gnus-sum.el
index 8c7334a..b37562d 100644
--- a/lisp/gnus-sum.el
+++ b/lisp/gnus-sum.el
@@ -12428,6 +12428,13 @@ If REVERSE, save parts that do not match TYPE."
 		(not (setq header (car (gnus-get-newsgroup-headers nil t)))))
 	    ()				; Malformed head.
 	  (unless (gnus-summary-article-sparse-p (mail-header-number header))
+            (when (and (bound-and-true-p gnus-registry-enabled)
+                       (not (gnus-ephemeral-group-p (car where))))
+              (gnus-registry-handle-action
+               (mail-header-id header) nil
+               (gnus-group-prefixed-name (car where) gnus-override-method)
+               (mail-header-subject header)
+               (mail-header-from header)))
 	    (when (and (stringp id)
 		       (or
 			(not (string= (gnus-group-real-name group)
-- 
1.7.5.4

[PATCH 3/5] Add `gnus-select-group-with-message-id'

[Dave Abrahams]

---
 lisp/gnus-int.el |   43 +++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 43 insertions(+), 0 deletions(-)

diff --git a/lisp/gnus-int.el b/lisp/gnus-int.el
index 1190d79..8a00c4a 100644
--- a/lisp/gnus-int.el
+++ b/lisp/gnus-int.el
@@ -533,6 +533,49 @@ If BUFFER, insert the article in that group."
 	     header
 	     (gnus-group-real-name group))))
 
+(defun gnus-select-group-with-message-id (group message-id)
+  "Activate and select GROUP with the given MESSAGE-ID selected.
+Returns the article number of the message.
+
+If GROUP is not already selected, the message will be the only one in
+the group's summary.
+"
+  ;; TODO: is there a way to know at this point whether the group will
+  ;; be newly-selected?  If so we could clean up the logic at the end
+  ;;
+  ;; save the new group's display parameter, if any, so we
+  ;; can replace it temporarily with zero.
+  (let ((saved-display
+         (gnus-group-get-parameter group 'display :allow-list)))
+
+    ;; Tell gnus we really don't want any articles 
+    (gnus-group-set-parameter group 'display 0)
+
+    (unwind-protect
+        (gnus-summary-read-group-1
+         group (not :show-all) :no-article (not :kill-buffer)
+         ;; The combination of no-display and this dummy list of
+         ;; articles to select somehow makes it possible to open a
+         ;; group with no articles in it.  Black magic.
+         :no-display '(-1); select-articles
+         )
+      ;; Restore the new group's display parameter
+      (gnus-group-set-parameter group 'display saved-display)))
+
+  ;; The summary buffer was suppressed by :no-display above.
+  ;; Create it now and insert the message
+  (let ((group-is-new (gnus-summary-setup-buffer group)))
+    (condition-case err
+        (let ((article-number 
+               (gnus-summary-insert-subject message-id)))
+          (unless article-number
+            (signal 'error "message-id not in group"))
+          (gnus-summary-select-article nil nil nil article-number)
+          article-number)
+      ;; Clean up the new summary and propagate the error
+      (error (when group-is-new (gnus-summary-exit))
+             (apply 'signal err)))))
+
 (defun gnus-warp-to-article ()
   "Warps from an article in a virtual group to the article in its
 real group. Does nothing on a real group."
-- 
1.7.5.4

[PATCH 4/5] Add `gnus-try-warping-via-registry()'

[Dave Abrahams]

The new function attempts to warp to the article based on group
information stored for the article in the registry.
---
 lisp/gnus-int.el |   50 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 50 insertions(+), 0 deletions(-)

diff --git a/lisp/gnus-int.el b/lisp/gnus-int.el
index 8a00c4a..4ae6e2a 100644
--- a/lisp/gnus-int.el
+++ b/lisp/gnus-int.el
@@ -576,6 +576,56 @@ the group's summary.
       (error (when group-is-new (gnus-summary-exit))
              (apply 'signal err)))))
 
+(defun gnus-simplify-group-name (group)
+  "Return the simplest representation of the name of GROUP.
+This is the string that Gnus uses to identify the group."
+  (gnus-group-prefixed-name
+   (gnus-group-real-name group)
+   (gnus-group-method group)))
+
+;; largely based on nnir-warp-to-article
+(defun gnus-try-warping-via-registry ()
+  "Attempt to warp to the current article's source group based on
+data stored in the registry."
+  (interactive)
+  (when (gnus-summary-article-header)
+    (let* ((message-id (mail-header-id (gnus-summary-article-header)))
+           ;; Retrieve the message's group(s) from the registry
+           (groups (gnus-registry-get-id-key message-id 'group))
+           ;; If starting from an ephemeral group, this describes
+           ;; how to restore the window configuration
+           (quit-config
+            (gnus-ephemeral-group-p gnus-newsgroup-name))
+           (seen-groups (list (gnus-group-group-name))))
+
+      (catch 'found
+        (dolist (group (mapcar 'gnus-simplify-group-name groups))
+
+          ;; skip over any groups we really don't want to warp to.
+          (unless (or (member group seen-groups)
+                      (gnus-ephemeral-group-p group)          ;; any ephemeral group
+                      (memq (car (gnus-find-method-for-group group))
+                            '(nnir))) ;; Specific methods; this list may need to expand.
+
+            ;; remember that we've seen this group already
+            (push group seen-groups)
+
+            ;; first exit from any ephemeral summary buffer.
+            (when quit-config
+              (gnus-summary-exit)
+              ;; and if the ephemeral summary buffer in turn came from another
+              ;; summary buffer we have to clean that summary up too.
+              (when (eq (cdr quit-config) 'summary)
+                (gnus-summary-exit))
+              ;; remember that we've already done this part
+              (setq quit-config nil))
+
+            ;; Try to activate the group.  If that fails, just move
+            ;; along.  We may have more groups to work with
+            (ignore-errors
+                (gnus-select-group-with-message-id group message-id))
+            (throw 'found t)))))))
+
 (defun gnus-warp-to-article ()
   "Warps from an article in a virtual group to the article in its
 real group. Does nothing on a real group."
-- 
1.7.5.4

[PATCH 5/5] Enable registry-warping as a fallback if warping via the current backend fails.

[Dave Abrahams]

---
 lisp/gnus-int.el |    8 +++++---
 1 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/lisp/gnus-int.el b/lisp/gnus-int.el
index 4ae6e2a..d858c3a 100644
--- a/lisp/gnus-int.el
+++ b/lisp/gnus-int.el
@@ -632,9 +632,11 @@ real group. Does nothing on a real group."
   (interactive)
   (let ((gnus-command-method
 	 (gnus-find-method-for-group gnus-newsgroup-name)))
-    (when (gnus-check-backend-function
-	   'warp-to-article (car gnus-command-method))
-      (funcall (gnus-get-function gnus-command-method 'warp-to-article)))))
+    (or
+     (when (gnus-check-backend-function
+            'warp-to-article (car gnus-command-method))
+       (funcall (gnus-get-function gnus-command-method 'warp-to-article)))
+     (gnus-try-warping-via-registry))))
 
 (defun gnus-request-head (article group)
   "Request the head of ARTICLE in GROUP."
-- 
1.7.5.4

Re: [PATCH 0/5] *** Resubmit: Warping via the registry ***

[Ted Zlatanov]

On Thu, 15 Mar 2012 14:23:08 -0400 Dave Abrahams <dave@boostpro.com> wrote: 

DA> Note: I submitted this patch series back in October
DA> (http://permalink.gmane.org/gmane.emacs.gnus.general/80250).  It still
DA> applies perfectly, but I rebased just in case.  I'd really appreciate
DA> it if this series could get some attention.  Further explanation of
DA> the motivation for this series is in
DA> http://article.gmane.org/gmane.emacs.gnus.general/80277. Thanks!

DA> This patch series implements the ability to warp to a message via
DA> information stored in the Gnus registry.  From a user's point-of-view,
DA> this means that articles brought in from other groups by
DA> gnus-*-refer-* can be used as a jumping-off-point for further
DA> references.

Sorry for forgetting about this.  I think you were still waiting on your
papers back then.  I'm OK with this patch.  If an XEmacs user could try
it too, that would be very helpful, but I think it's reasonable and
generally useful.

Ted

Re: [PATCH 0/5] *** Resubmit: Warping via the registry ***

[Lars Magne Ingebrigtsen]

Dave Abrahams <dave@boostpro.com> writes:

> Note: I submitted this patch series back in October
> (http://permalink.gmane.org/gmane.emacs.gnus.general/80250).  It still
> applies perfectly, but I rebased just in case.  I'd really appreciate
> it if this series could get some attention.  Further explanation of
> the motivation for this series is in
> http://article.gmane.org/gmane.emacs.gnus.general/80277. Thanks!

Thanks; applied.

I've rearranged the code a bit to silence the resulting compilation
warnings.

-- 
(domestic pets only, the antidote for overdose, milk.)
  bloggy blog http://lars.ingebrigtsen.no/