feat(wpcarro/emacs): Support calling sudo on a remote buffer

While pattern-matching in Elisp is a bit unsightly, it works :)

Change-Id: I6766147095823f1a4e233832b0ef21f4c486e023
Reviewed-on: https://cl.tvl.fyi/c/depot/+/5452
Tested-by: BuildkiteCI
Reviewed-by: wpcarro <wpcarro@gmail.com>
Autosubmit: wpcarro <wpcarro@gmail.com>

users/wpcarro/emacs/.emacs.d/wpc/ssh.el

@@ -41,7 +41,9 @@
 ;; enables ControlMaster.
 (setq tramp-use-ssh-controlmaster-options nil)
 
-(defcustom ssh-hosts '("wpcarro@wpcarro.dev")
+(defcustom ssh-hosts '("wpcarro@wpcarro.dev"
+                       "foundation"
+                       "edge")
   "List of hosts to which I commonly connect.")
 
 (defun ssh-sudo-buffer ()
@@ -49,7 +51,10 @@
   (interactive)
   (with-current-buffer (current-buffer)
     (if (s-starts-with? "/ssh:" buffer-file-name)
-        (message "[ssh.el] calling ssh-sudo-buffer for remote files isn't currently supported")
+        (pcase (s-split ":" buffer-file-name)
+          (`(,one ,two ,three) (find-file (format "/ssh:%s|sudo:%s:%s" two two three))))
+        (find-file
+         (s-join ":" (-insert-at 2 "|sudo" (s-split ":" buffer-file-name))))
       (find-file (format "/sudo::%s" buffer-file-name)))))
 
 (defun ssh-cd-home ()