Patch for bug in w3m-generate-new-buffer

[Vladimir Sedach <vas@xxxxxxxxxx>]

Hello,

There was a serious bug introduced on 2017-10-13 to
w3m-generate-new-buffer: new buffers would always get number 1, there
would be duplicate buffers with number 1. You can verify this by opening
a new w3m buffer (via w3m-search-new-session, for example) when multiple
w3m buffers are already open, and trying to use w3m-previous-buffer.

This bug also masked a problem with the new LAST parameter to
w3m-copy-buffer in w3m-view-this-url-1.

A patch is attached.

Thank you,
Vladimir

Index: w3m.el
===================================================================
RCS file: /storage/cvsroot/emacs-w3m/w3m.el,v
retrieving revision 1.1700
diff -u -p -r1.1700 w3m.el
--- w3m.el	21 Jan 2018 23:05:45 -0000	1.1700
+++ w3m.el	8 Feb 2018 10:44:12 -0000
@@ -7192,7 +7192,7 @@ launches the current session, i.e., the
 	      (parent (current-buffer)))
 	  (setq pos (point-marker)
 		buffer (w3m-copy-buffer
-			nil nil nil empty w3m-new-session-in-background t))
+			nil nil nil empty w3m-new-session-in-background nil))
 	  (when w3m-new-session-in-background
 	    (set-buffer buffer))
 	  (setq w3m-parent-session-buffer parent)
Index: w3m-util.el
===================================================================
RCS file: /storage/cvsroot/emacs-w3m/w3m-util.el,v
retrieving revision 1.185
diff -u -p -r1.185 w3m-util.el
--- w3m-util.el	5 Feb 2018 01:26:09 -0000	1.185
+++ w3m-util.el	8 Feb 2018 10:44:12 -0000
@@ -446,33 +446,23 @@ An argument of nil means kill the curren
 (defun w3m-generate-new-buffer (name &optional next)
   "Create and return a buffer with a name based on NAME.
 Make the new buffer the next of the current buffer if NEXT is non-nil."
-  (when (string-match "<[0-9]+>\\'" name)
-    (setq name (substring name 0 (match-beginning 0))))
-  (let* ((w3m-fb-mode nil)
-	 (buffers (w3m-list-buffers))
-	 (regexp (concat "\\`" (regexp-quote name) "\\(?:<[0-9]+>\\)?\\'"))
-	 (siblings (delq nil
-			 (mapcar
-			  (lambda (buffer)
-			    (when (string-match regexp (buffer-name buffer))
-			      buffer))
-			  buffers)))
-	 youngers cur number num)
-    (if (and next
-	     (setq youngers (cdr (memq (setq cur (current-buffer)) siblings))))
-	(progn
-	  (setq number (1+ (w3m-buffer-number cur))
-		num (+ 1 (length youngers)
-		       (w3m-buffer-number (car (reverse youngers)))))
-	  (dolist (buffer (reverse youngers))
-	    (w3m-buffer-set-number buffer (setq num (1- num))))
-	  (setq num number)
-	  (dolist (buffer youngers)
-	    (w3m-buffer-set-number buffer (setq num (1+ num))))
-	  (generate-new-buffer (format "%s<%d>" name number)))
-      (if (setq number (w3m-buffer-number (car (nreverse siblings))))
-	  (generate-new-buffer (format "%s<%d>" name (1+ number)))
-	(generate-new-buffer name)))))
+  (if w3m-use-title-buffer-name
+      (let* ((tailbufs (let ((w3m-fb-mode nil))
+                         (let ((all-w3m-buffers (w3m-list-buffers)))
+                           (if next
+                               (memq (current-buffer) all-w3m-buffers)
+                             (last all-w3m-buffers)))))
+	     (new-buffer-number (w3m-buffer-number (car tailbufs))))
+	(when (string-match "\\*w3m\\*\\(<\\([0-9]+\\)>\\)?\\'" name)
+	  (setq name "*w3m*"))
+	(if (and tailbufs new-buffer-number)
+            (let ((n (1+ new-buffer-number)))
+              (dolist (buf (cdr tailbufs))
+                (w3m-buffer-set-number buf (setq n (1+ n))))
+              (generate-new-buffer
+               (format "%s<%d>" name (1+ new-buffer-number))))
+	  (generate-new-buffer name)))
+    (generate-new-buffer name)))

 (defun w3m-buffer-name-lessp (x y)
   "Return t if first arg buffer's name is less than second."
Index: ChangeLog
===================================================================
RCS file: /storage/cvsroot/emacs-w3m/ChangeLog,v
retrieving revision 1.3645
diff -u -p -r1.3645 ChangeLog
--- ChangeLog	5 Feb 2018 01:26:08 -0000	1.3645
+++ ChangeLog	8 Feb 2018 10:44:12 -0000
@@ -1,3 +1,12 @@
+2018-02-08  Vladimir Sedach  <vas@xxxxxxxxxx>
+
+	* w3m.el (w3m-view-this-url-1): Fix LAST parameter to w3m-copy-buffer
+	to make new buffer go after the current buffer, as intended in revision
+	1.1691 on 2017-10-13
+
+	* w3m-util.el (w3m-generate-new-buffer): Fix bug introduced in revision
+	1.3628 on 2017-10-13 where new buffers were always assigned number 1.
+
 2018-02-05  Katsumi Yamaoka  <yamaoka@xxxxxxx>

 	* w3m-util.el (w3m-string-match-url-components)