4 files changed, 69 insertions, 28 deletions

diff --git a/lisp/gnus/ChangeLog b/lisp/gnus/ChangeLog
index a8065fc5ca4..400abd51c27 100644
--- a/lisp/gnus/ChangeLog
+++ b/lisp/gnus/ChangeLog
@@ -1,3 +1,14 @@
+2011-07-23  Andrew Cohen  <cohen@andy.bu.edu>
+
+        * nnir.el (nnir-search-thread): New function to make an nnir group
+        based on a thread query.
+
+        * gnus-sum.el (gnus-refer-thread-use-nnir): New variable to control use
+        of nnir in thread referral.
+        (gnus-summary-refer-thread): Use it.
+
+        * nnimap.el (nnimap-request-thread): Use it.
+
 2011-07-20  Lars Magne Ingebrigtsen  <larsi@gnus.org>
 
         * shr.el (shr-tag-comment): Ignore HTML comments.
diff --git a/lisp/gnus/gnus-sum.el b/lisp/gnus/gnus-sum.el
index 6e8fc63d79f..5917c9d7cef 100644
--- a/lisp/gnus/gnus-sum.el
+++ b/lisp/gnus/gnus-sum.el
@@ -118,6 +118,13 @@ If t, fetch all the available old headers."
   :type '(choice number
                  (sexp :menu-tag "other" t)))
 
+(defcustom gnus-refer-thread-use-nnir nil
+  "*Use nnir to search an entire server when referring threads. A
+nil value will only search for thread-related articles in the
+current group."
+  :group 'gnus-thread
+  :type 'boolean)
+
 (defcustom gnus-summary-make-false-root 'adopt
   "*nil means that Gnus won't gather loose threads.
 If the root of a thread has expired or been read in a previous
@@ -8972,11 +8979,16 @@ Return the number of articles fetched."
     result))
 
 (defun gnus-summary-refer-thread (&optional limit)
-  "Fetch all articles in the current thread.
-If no backend-specific 'request-thread function is available
-fetch LIMIT (the numerical prefix) old headers. If LIMIT is nil
-fetch what's specified by the `gnus-refer-thread-limit'
-variable."
+  "Fetch all articles in the current thread. For backends that
+know how to search for threads (currently only 'nnimap) a
+non-numeric prefix arg will use nnir to search the entire
+server; without a prefix arg only the current group is
+searched. If the variable `gnus-refer-thread-use-nnir' is
+non-nil the prefix arg has the reverse meaning. If no
+backend-specific 'request-thread function is available fetch
+LIMIT (the numerical prefix) old headers. If LIMIT is
+non-numeric or nil fetch the number specified by the
+`gnus-refer-thread-limit' variable."
   (interactive "P")
   (gnus-warp-to-article)
   (let* ((header (gnus-summary-article-header))
@@ -8984,13 +8996,16 @@ variable."
          (gnus-inhibit-demon t)
          (gnus-summary-ignore-duplicates t)
          (gnus-read-all-available-headers t)
-         (limit (if limit (prefix-numeric-value limit)
-                  gnus-refer-thread-limit))
+         (gnus-refer-thread-use-nnir
+          (if (and (not (null limit)) (listp limit))
+              (not gnus-refer-thread-use-nnir) gnus-refer-thread-use-nnir))
          (new-headers
           (if (gnus-check-backend-function
                'request-thread gnus-newsgroup-name)
               (gnus-request-thread header gnus-newsgroup-name)
-            (let* ((last (if (numberp limit)
+            (let* ((limit (if (numberp limit) (prefix-numeric-value limit)
+                            gnus-refer-thread-limit))
+                   (last (if (numberp limit)
                              (min (+ (mail-header-number header)
                                      limit)
                                   gnus-newsgroup-highest)
@@ -9005,17 +9020,19 @@ variable."
                        (regexp-opt (append refs (list id subject)))))))
               (gnus-fetch-headers (list last) (if (numberp limit)
                                                   (* 2 limit) limit) t)))))
-    (dolist (header new-headers)
-      (when (member (mail-header-number header) gnus-newsgroup-unselected)
-        (push (mail-header-number header) gnus-newsgroup-unreads)
-        (setq gnus-newsgroup-unselected
-              (delete (mail-header-number header) gnus-newsgroup-unselected))))
-    (setq gnus-newsgroup-headers
-          (gnus-delete-duplicate-headers
-           (gnus-merge
-            'list gnus-newsgroup-headers new-headers
-            'gnus-article-sort-by-number)))
-    (gnus-summary-limit-include-thread id)))
+    (when (listp new-headers)
+      (dolist (header new-headers)
+        (when (member (mail-header-number header) gnus-newsgroup-unselected)
+          (push (mail-header-number header) gnus-newsgroup-unreads)
+          (setq gnus-newsgroup-unselected
+                (delete (mail-header-number header)
+                        gnus-newsgroup-unselected))))
+      (setq gnus-newsgroup-headers
+            (gnus-delete-duplicate-headers
+             (gnus-merge
+              'list gnus-newsgroup-headers new-headers
+              'gnus-article-sort-by-number)))
+      (gnus-summary-limit-include-thread id))))
 
 (defun gnus-summary-refer-article (message-id)
   "Fetch an article specified by MESSAGE-ID."
diff --git a/lisp/gnus/nnimap.el b/lisp/gnus/nnimap.el
index 385522759b6..8a0d635ef7b 100644
--- a/lisp/gnus/nnimap.el
+++ b/lisp/gnus/nnimap.el
@@ -1566,15 +1566,17 @@ textual parts.")
                   (articles &optional limit force-new dependencies))
 
 (deffoo nnimap-request-thread (header &optional group server)
-  (when (nnimap-possibly-change-group group server)
-    (let* ((cmd (nnimap-make-thread-query header))
-           (result (with-current-buffer (nnimap-buffer)
-                     (nnimap-command  "UID SEARCH %s" cmd))))
-      (when result
-        (gnus-fetch-headers
-         (and (car result) (delete 0 (mapcar #'string-to-number
-                                             (cdr (assoc "SEARCH" (cdr result))))))
-         nil t)))))
+  (if gnus-refer-thread-use-nnir 
+      (nnir-search-thread header)
+    (when (nnimap-possibly-change-group group server)
+      (let* ((cmd (nnimap-make-thread-query header))
+             (result (with-current-buffer (nnimap-buffer)
+                       (nnimap-command  "UID SEARCH %s" cmd))))
+        (when result
+          (gnus-fetch-headers
+           (and (car result) (delete 0 (mapcar #'string-to-number
+                                               (cdr (assoc "SEARCH" (cdr result))))))
+           nil t))))))
 
 (defun nnimap-possibly-change-group (group server)
   (let ((open-result t))
diff --git a/lisp/gnus/nnir.el b/lisp/gnus/nnir.el
index 9840dddcb66..e6420a4d7bb 100644
--- a/lisp/gnus/nnir.el
+++ b/lisp/gnus/nnir.el
@@ -289,6 +289,7 @@ is `(valuefunc member)'."
   (autoload 'nnimap-buffer "nnimap")
   (autoload 'nnimap-command "nnimap")
   (autoload 'nnimap-possibly-change-group "nnimap")
+  (autoload 'nnimap-make-thread-query "nnimap")
   (autoload 'gnus-registry-action "gnus-registry")
   (defvar gnus-registry-install))
 
@@ -1649,6 +1650,16 @@ server is of form 'backend:name'."
     (nnir-open-server server)))
 
 
+(defun nnir-search-thread (header)
+  "Make an nnir group based on the thread containing the article header"
+  (let ((parm (list
+               (cons 'query
+                     (nnimap-make-thread-query header))
+               (cons 'criteria "")
+               (cons 'server (gnus-method-to-server
+                              (gnus-find-method-for-group
+                               gnus-newsgroup-name))))))
+    (gnus-group-make-nnir-group nil parm)))
 
 ;; unused?
 (defun nnir-artlist-groups (artlist)