bug#19863: 20.0.50; browse-url.el: Add support for Conkeror

[vibhavp]

Conkeror[1] is a web browser with an Emacs-like navigation interface. The
following patch add's support for Conkeror to browse-url.el. The code
uses the words "buffer" instead of "tabs", to keep consistency with
Conkeror's interface. 

[1]: http://conkeror.org/

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 24cf80a..cccd57f 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,12 @@
+2015-02-14  Vibhav Pant  <vibhavp@gmail.com>
+
+       * net/browse-url.el (browse-url-browser-function): Add "Conkeror".
+       (browse-url-conkeror-program, browse-url-conkeror-arguments)
+       (browse-url-conkeror-new-window-is-buffer): New defcustoms.
+       (browse-url-default-browser): Check for `browse-url-conkeror'
+       and call `browse-url-conkeror-program'.
+       (browse-url-conkeror): New command.
+
 2015-02-14  Stefan Monnier  <monnier@iro.umontreal.ca>
 
        * emacs-lisp/cl-preloaded.el (cl-struct-define): Register as children
diff --git a/lisp/net/browse-url.el b/lisp/net/browse-url.el
index 42fb954..6cbf393 100644
--- a/lisp/net/browse-url.el
+++ b/lisp/net/browse-url.el
@@ -42,6 +42,7 @@
 ;; browse-url-netscape                Netscape    1.1b1
 ;; browse-url-mosaic                  XMosaic/mMosaic <= 2.4
 ;; browse-url-cci                     XMosaic     2.5
+;; browse-url-conkeror                Conkeror    Dont know
 ;; browse-url-w3                      w3          0
 ;; browse-url-w3-gnudoit              w3 remotely
 ;; browse-url-text-*                 Any text browser     0
@@ -236,6 +237,7 @@ regexp should probably be \".\" to specify a default 
browser."
          (function-item :tag "Netscape" :value  browse-url-netscape)
          (function-item :tag "Mosaic" :value  browse-url-mosaic)
          (function-item :tag "Mosaic using CCI" :value  browse-url-cci)
+         (function-item :tag "Conkeror" :value  browse-url-conkeror)
          (function-item :tag "Text browser in an xterm window"
                         :value browse-url-text-xterm)
          (function-item :tag "Text browser in an Emacs window"
@@ -413,6 +415,13 @@ functionality is not available there."
   :type 'boolean
   :group 'browse-url)
 
+(defcustom browse-url-conkeror-new-window-is-buffer nil
+  "Whether to open up new windows in a buffer or a new window.
+If non-nill, then open the URL in a new buffer rather than a new window if
+`browse-url-conkeror' is asked to open it in a new window"
+  :type 'boolean
+  :group 'browse-url)
+
 (defcustom browse-url-galeon-new-window-is-tab nil
   "Whether to open up new windows in a tab or a new window.
 If non-nil, then open the URL in a new tab rather than a new window if
@@ -459,6 +468,17 @@ commands reverses the effect of this variable.  Requires 
Netscape version
   :type 'string
   :group 'browse-url)
 
+(defcustom browse-url-conkeror-program "conkeror"
+  "The name by which to invoke Conkeror."
+  :type 'string
+  :version "25.1"
+  :group 'browse-url)
+
+(defcustom browse-url-conkeror-arguments nil
+  "A list of strings to pass to Conkeror as arguments."
+  :type '(repeat (string :tag "Argument"))
+  :group 'browse-url)
+
 (defcustom browse-url-filename-alist
   `(("^/\\(ftp@\\|anonymous@\\)?\\([^:]+\\):/*" . "ftp://\\2/";)
     ;; The above loses the username to avoid the browser prompting for
@@ -933,6 +953,7 @@ used instead of `browse-url-new-window-flag'."
     ((executable-find browse-url-kde-program) 'browse-url-kde)
     ((executable-find browse-url-netscape-program) 'browse-url-netscape)
     ((executable-find browse-url-mosaic-program) 'browse-url-mosaic)
+    ((executable-find browse-url-conkeror-program) 'browse-url-conkeror)
     ((executable-find browse-url-xterm-program) 'browse-url-text-xterm)
     ((locate-library "w3") 'browse-url-w3)
     (t
@@ -1392,6 +1413,41 @@ used instead of `browse-url-new-window-flag'."
   (process-send-string "browse-url" "disconnect\r\n")
   (delete-process "browse-url"))
 
+;; --- Conkeror ---
+;;;###autoload
+(defun browse-url-conkeror (url &optional new-window)
+  "Ask the Conkeror WWW browser to load URL.
+Default to the URL around or before point. The strings in the variable
+`browse-url-conkeror-arguments' are also passed to Conkeror.
+
+When called interactively, if variable `browse-url-new-window-flag'
+is non-nil, load the document in a new Conkeror window, otherwise use a random
+existing one. A non-nil interactive prefix argument reverses the effect of
+`browse-url-new-window-flag'
+
+If `browse-url-conkeror-new-window-is-buffer' then whenever a document would
+otherwise be loaded in a new window, it is loaded in a new buffer in an 
existing
+window instead.
+
+When called non-interatively, optional second argument NEW-WINDOW is used 
instead of
+`browse-url-new-window-flag'"
+  (interactive (browse-url-interactive-arg "URL: "))
+  (setq url (browse-url-encode-url url))
+  (let* ((process-environment (browse-url-process-environment)))
+    (apply 'start-process (format "conkeror %s" url)
+          nil
+          browse-url-conkeror-program
+          (append
+           browse-url-conkeror-arguments
+           (list
+            "-e"
+            (format "load_url_in_new_%s('%s')"
+                    (if (browse-url-maybe-new-window new-window)
+                        (if browse-url-conkeror-new-window-is-buffer
+                            "buffer"
+                          "window")
+                      "buffer")
+                    url))))))
 ;; --- W3 ---
 
 ;; External.