1 files changed, 14 insertions, 7 deletions

@@ -25,7 +25,8 @@ that the latter is deprecated in Emacs 28+."
     (viewer default-args &optional (prompt "URL: ")
             &key
             (custom-group '+browse-url)
-            (name (format "+browse-url-with-%s" viewer)))
+            (name (format "+browse-url-with-%s" viewer))
+            (fallback #'browse-url-generic))
   "Create a `browse-url' handler function that calls VIEWER on the url.
 Also create a `customize' setting in CUSTOM-GROUP for VIEWER's
 arguments.  DEFAULT-ARGS specifies the default arguments that
@@ -33,7 +34,10 @@ setting should have.  PROMPT will be shown to user in the
 function's `interactive' spec, as an argument to
 `browse-url-interactive-arg'.  The resulting function will be
 named NAME, defaulting to \"+browse-url-with-VIEWER\", and the variable
-\"NAME-args\"."
+\"NAME-args\".
+
+If FALLBACK is non-nil, it's a function to fallback on if the
+`start-process' call fails in anyway."
   (declare (indent 1))
   `(progn
      (defcustom ,(intern (format "%s-args" name))
@@ -41,16 +45,19 @@ named NAME, defaulting to \"+browse-url-with-VIEWER\", and the variable
        ,(format "Arguments to pass to %s in `%s'." viewer name)
        :type '(repeat :tag "Command-line argument" string)
        :group ',custom-group)
-     (defun ,(intern name) (url &optional _new-window)
+     (defun ,(intern name) (url &optional new-window)
        ,(format "Open URL in %s." viewer)
        (interactive (browse-url-interactive-arg ,prompt))
        (let* ((url (browse-url-encode-url url))
               (process-environment (browse-url-process-environment)))
          (message ,(format "Opening %%s in %s..." viewer) url)
-         (apply #'start-process
-                (concat ,viewer " " url) nil
-                ,viewer
-                (append ,(intern (format "%s-args" name)) (list url)))))))
+         (unless (ignore-errors
+                   (apply #'start-process
+                          (concat ,viewer " " url) nil
+                          ,viewer
+                          (append ,(intern (format "%s-args" name))
+                                  (list url))))
+           (funcall fallback url new-window))))))
 
 ;; Reference implementation: mpv
 (+browse-url-make-external-viewer-handler "mpv" nil "Video URL: ")