Provide new gnus-mode, derive all gnus major modes from this

* lisp/gnus/gnus.el (gnus-mode): New do-nothing major mode, derived
  from special mode.
* lisp/gnus/gnus-sum.el (gnus-summary-mode): Change from a function to
  a major mode, derive from gnus-mode.
  (gnus-summary-setup-buffer): Change call a bit -- can no longer pass
  an argument to the mode function.
* lisp/gnus/gnus-srvr.el (gnus-browse-mode): Derive from gnus-mode.
  (gnus-server-setup-buffer): Remove unnecessary function.
  (gnus-enter-server-buffer): Call gnus-server-mode here, and call it
  whether the server buffer already existed or not.
  (gnus-server-mode): Change from a function to a major mode.
  (gnus-server-mode-hook): Delete custom option, this is automatically
  created.
* lisp/gnus/gnus-salt.el (gnus-tree-mode): Derive from gnus-mode.
  (gnus-tree-mode-hook): Delete custom option, this is automatically
  created.
* lisp/gnus/gnus-kill.el (gnus-kill-file-mode-hook): Delete custom
  option.
* lisp/gnus/gnus-group.el (gnus-group-mode):
* lisp/gnus/gnus-art.el (gnus-article-mode):
* lisp/gnus/gnus-agent.el (gnus-category-mode): Derive from gnus-mode.
  (gnus-category-mode-hook): Delete custom option.

(Bug#33263)

1 files changed, 26 insertions, 25 deletions

diff --git a/lisp/gnus/gnus-sum.el b/lisp/gnus/gnus-sum.el
index f9fae3792b1..1c4be09e2e9 100644
--- a/lisp/gnus/gnus-sum.el
+++ b/lisp/gnus/gnus-sum.el
@@ -1842,8 +1842,6 @@ increase the score of each group you read."
 ;;; Gnus summary mode
 ;;;
 
-(put 'gnus-summary-mode 'mode-class 'special)
-
 (defvar gnus-article-commands-menu)
 
 ;; Non-orthogonal keys
@@ -3052,10 +3050,8 @@ When FORCE, rebuild the tool bar."
 
 (defvar bidi-paragraph-direction)
 
-(defun gnus-summary-mode (&optional group)
+(define-derived-mode gnus-summary-mode gnus-mode "Summary"
   "Major mode for reading articles.
-
-All normal editing commands are switched off.
 \\<gnus-summary-mode-map>
 Each line in this buffer represents one article.  To read an
 article, you can, for instance, type `\\[gnus-summary-next-page]'.  To move forwards
@@ -3072,24 +3068,16 @@ buffer; read the info pages for more information (`\\[gnus-info-find-node]').
 The following commands are available:
 
 \\{gnus-summary-mode-map}"
-  ;; FIXME: Use define-derived-mode.
-  (interactive)
-  (kill-all-local-variables)
   (let ((gnus-summary-local-variables gnus-newsgroup-variables))
     (gnus-summary-make-local-variables))
   (gnus-summary-make-local-variables)
-  (setq gnus-newsgroup-name group)
   (when (gnus-visual-p 'summary-menu 'menu)
     (gnus-summary-make-menu-bar)
     (gnus-summary-make-tool-bar))
   (gnus-make-thread-indent-array)
   (gnus-simplify-mode-line)
-  (setq major-mode 'gnus-summary-mode)
-  (setq mode-name "Summary")
-  (use-local-map gnus-summary-mode-map)
   (buffer-disable-undo)
-  (setq buffer-read-only t
-	show-trailing-whitespace nil
+  (setq show-trailing-whitespace nil
 	truncate-lines t
 	bidi-paragraph-direction 'left-to-right)
   (add-to-invisibility-spec '(gnus-sum . t))
@@ -3100,14 +3088,13 @@ The following commands are available:
   (make-local-variable 'gnus-summary-dummy-line-format)
   (make-local-variable 'gnus-summary-dummy-line-format-spec)
   (make-local-variable 'gnus-summary-mark-positions)
+  (make-local-variable 'gnus-article-buffer)
+  (make-local-variable 'gnus-article-current)
+  (make-local-variable 'gnus-original-article-buffer)
   (add-hook 'pre-command-hook 'gnus-set-global-variables nil t)
-  (gnus-run-mode-hooks 'gnus-summary-mode-hook)
-  (turn-on-gnus-mailing-list-mode)
   (mm-enable-multibyte)
   (set (make-local-variable 'bookmark-make-record-function)
-       'gnus-summary-bookmark-make-record)
-  (gnus-update-format-specifications nil 'summary 'summary-mode 'summary-dummy)
-  (gnus-update-summary-mark-positions))
+       'gnus-summary-bookmark-make-record))
 
 (defun gnus-summary-make-local-variables ()
   "Make all the local summary buffer variables."
@@ -3478,8 +3465,11 @@ display only a single character."
 					       (current-buffer))))))
 
 (defun gnus-summary-setup-buffer (group)
-  "Initialize summary buffer.
-If the setup was successful, non-nil is returned."
+  "Initialize summary buffer for GROUP.
+This function does all setup work that relies on the specific
+value of GROUP, and puts the buffer in `gnus-summary-mode'.
+
+Returns non-nil if the setup was successful."
   (let ((buffer (gnus-summary-buffer-name group))
 	(dead-name (concat "*Dead Summary "
 			   (gnus-group-decoded-name group) "*")))
@@ -3493,13 +3483,15 @@ If the setup was successful, non-nil is returned."
 	  (not gnus-newsgroup-prepared))
       (set-buffer (gnus-get-buffer-create buffer))
       (setq gnus-summary-buffer (current-buffer))
-      (gnus-summary-mode group)
+      (gnus-summary-mode)
       (when (gnus-group-quit-config group)
 	(set (make-local-variable 'gnus-single-article-buffer) nil))
-      (make-local-variable 'gnus-article-buffer)
-      (make-local-variable 'gnus-article-current)
-      (make-local-variable 'gnus-original-article-buffer)
       (setq gnus-newsgroup-name group)
+      (turn-on-gnus-mailing-list-mode)
+      ;; These functions don't currently depend on GROUP, but might in
+      ;; the future.
+      (gnus-update-format-specifications nil 'summary 'summary-mode 'summary-dummy)
+      (gnus-update-summary-mark-positions)
       ;; Set any local variables in the group parameters.
       (gnus-summary-set-local-parameters gnus-newsgroup-name)
       t)))
@@ -3935,6 +3927,15 @@ If SELECT-ARTICLES, only select those articles from GROUP."
 (defun gnus-summary-read-group-1 (group show-all no-article
 					kill-buffer no-display
 					&optional select-articles)
+  "Display articles and threads in a Summary buffer for GROUP."
+  ;; This function calls `gnus-summary-setup-buffer' to create the
+  ;; buffer, put it in `gnus-summary-mode', and set local variables;
+  ;; `gnus-select-newsgroup' to update the group's active and marks
+  ;; from the server; and `gnus-summary-prepare' to actually insert
+  ;; lines for articles.  The rest of the function is mostly concerned
+  ;; with limiting and positioning and windowing and other visual
+  ;; effects.
+
   ;; Killed foreign groups can't be entered.
   ;;  (when (and (not (gnus-group-native-p group))
   ;;	     (not (gnus-gethash group gnus-newsrc-hashtb)))