Use connection-local setting for tramp-remote-path

* doc/misc/tramp.texi (Remote programs): Mention connection-local
settings for `tramp-remote-path'.

* lisp/net/tramp-sh.el (tramp-get-remote-path): Expand connection-local
variables.

2 files changed, 117 insertions, 81 deletions

diff --git a/doc/misc/tramp.texi b/doc/misc/tramp.texi
index ea6ad15dc3d..ac5aa680d5e 100644
--- a/doc/misc/tramp.texi
+++ b/doc/misc/tramp.texi
@@ -1979,6 +1979,39 @@ preserves the path value, which can be used to update
 shell supports the login argument @samp{-l}.
 @end defopt
 
+Starting with Emacs 26, @code{tramp-remote-path} can be set per host
+via connection-local
+@ifinfo
+variables, @xref{Connection Variables, , , emacs}.
+@end ifinfo
+@ifnotinfo
+variables.
+@end ifnotinfo
+You could define your own search directories like this:
+
+@lisp
+@group
+(connection-local-set-profile-variables 'remote-path-with-bin
+   '((tramp-remote-path . ("~/bin" tramp-default-remote-path))))
+@end group
+
+@group
+(connection-local-set-profile-variables 'remote-path-with-apply-pub-bin
+   '((tramp-remote-path . ("/appli/pub/bin" tramp-default-remote-path))))
+@end group
+
+@group
+(connection-local-set-profiles
+   '(:application tramp :machine "randomhost") 'remote-path-with-bin)
+@end group
+
+@group
+(connection-local-set-profiles
+   '(:application tramp :user "anotheruser" :machine "anotherhost")
+     'remote-path-with-apply-pub-bin)
+@end group
+@end lisp
+
 When remote search paths are changed, local @value{tramp} caches must
 be recomputed.  To force @value{tramp} to recompute afresh, call
 @kbd{M-x tramp-cleanup-this-connection @key{RET}} or friends
diff --git a/lisp/net/tramp-sh.el b/lisp/net/tramp-sh.el
index 2b4399f8de7..edd9af489e2 100644
--- a/lisp/net/tramp-sh.el
+++ b/lisp/net/tramp-sh.el
@@ -5314,87 +5314,90 @@ Return ATTR."
 (defun tramp-get-remote-path (vec)
   "Compile list of remote directories for $PATH.
 Nonexistent directories are removed from spec."
-  (with-tramp-connection-property
-      ;; When `tramp-own-remote-path' is in `tramp-remote-path', we
-      ;; cache the result for the session only.  Otherwise, the result
-      ;; is cached persistently.
-      (if (memq 'tramp-own-remote-path tramp-remote-path)
-	  (tramp-get-connection-process vec)
-	vec)
-      "remote-path"
-    (let* ((remote-path (copy-tree tramp-remote-path))
-	   (elt1 (memq 'tramp-default-remote-path remote-path))
-	   (elt2 (memq 'tramp-own-remote-path remote-path))
-	   (default-remote-path
-	     (when elt1
-	       (or
-		(tramp-send-command-and-read
-		 vec "echo \\\"`getconf PATH 2>/dev/null`\\\"" 'noerror)
-		;; Default if "getconf" is not available.
-		(progn
-		  (tramp-message
-		   vec 3
-		   "`getconf PATH' not successful, using default value \"%s\"."
-		   "/bin:/usr/bin")
-		  "/bin:/usr/bin"))))
-	   (own-remote-path
-	    ;; The login shell could return more than just the $PATH
-	    ;; string.  So we use `tramp-end-of-heredoc' as marker.
-	    (when elt2
-	      (or
-	       (tramp-send-command-and-read
-		vec
-		(format
-		 "%s %s %s 'echo %s \\\"$PATH\\\"'"
-		 (tramp-get-method-parameter vec 'tramp-remote-shell)
-		 (mapconcat
-		  #'identity
-		  (tramp-get-method-parameter vec 'tramp-remote-shell-login)
-		  " ")
-		 (mapconcat
-		  #'identity
-		  (tramp-get-method-parameter vec 'tramp-remote-shell-args)
-		  " ")
-		 (tramp-shell-quote-argument tramp-end-of-heredoc))
-		'noerror (regexp-quote tramp-end-of-heredoc))
-	       (progn
-		 (tramp-message
-		  vec 2 "Could not retrieve `tramp-own-remote-path'")
-		 nil)))))
-
-      ;; Replace place holder `tramp-default-remote-path'.
-      (when elt1
-	(setcdr elt1
-		(append
-                 (split-string (or default-remote-path "") ":" 'omit)
-		 (cdr elt1)))
-	(setq remote-path (delq 'tramp-default-remote-path remote-path)))
-
-      ;; Replace place holder `tramp-own-remote-path'.
-      (when elt2
-	(setcdr elt2
-		(append
-                 (split-string (or own-remote-path "") ":" 'omit)
-		 (cdr elt2)))
-	(setq remote-path (delq 'tramp-own-remote-path remote-path)))
-
-      ;; Remove double entries.
-      (setq elt1 remote-path)
-      (while (consp elt1)
-	(while (and (car elt1) (setq elt2 (member (car elt1) (cdr elt1))))
-	  (setcar elt2 nil))
-	(setq elt1 (cdr elt1)))
-
-      ;; Remove non-existing directories.
-      (delq
-       nil
-       (mapcar
-	(lambda (x)
-	  (and
-	   (stringp x)
-	   (file-directory-p (tramp-make-tramp-file-name vec x 'nohop))
-	   x))
-	remote-path)))))
+  (with-current-buffer (tramp-get-connection-buffer vec)
+    ;; Expand connection-local variables.
+    (tramp-set-connection-local-variables vec)
+    (with-tramp-connection-property
+	;; When `tramp-own-remote-path' is in `tramp-remote-path', we
+	;; cache the result for the session only.  Otherwise, the
+	;; result is cached persistently.
+	(if (memq 'tramp-own-remote-path tramp-remote-path)
+	    (tramp-get-connection-process vec)
+	  vec)
+	"remote-path"
+      (let* ((remote-path (copy-tree tramp-remote-path))
+	     (elt1 (memq 'tramp-default-remote-path remote-path))
+	     (elt2 (memq 'tramp-own-remote-path remote-path))
+	     (default-remote-path
+	       (when elt1
+		 (or
+		  (tramp-send-command-and-read
+		   vec "echo \\\"`getconf PATH 2>/dev/null`\\\"" 'noerror)
+		  ;; Default if "getconf" is not available.
+		  (progn
+		    (tramp-message
+		     vec 3
+		     "`getconf PATH' not successful, using default value \"%s\"."
+		     "/bin:/usr/bin")
+		    "/bin:/usr/bin"))))
+	     (own-remote-path
+	      ;; The login shell could return more than just the $PATH
+	      ;; string.  So we use `tramp-end-of-heredoc' as marker.
+	      (when elt2
+		(or
+		 (tramp-send-command-and-read
+		  vec
+		  (format
+		   "%s %s %s 'echo %s \\\"$PATH\\\"'"
+		   (tramp-get-method-parameter vec 'tramp-remote-shell)
+		   (mapconcat
+		    #'identity
+		    (tramp-get-method-parameter vec 'tramp-remote-shell-login)
+		    " ")
+		   (mapconcat
+		    #'identity
+		    (tramp-get-method-parameter vec 'tramp-remote-shell-args)
+		    " ")
+		   (tramp-shell-quote-argument tramp-end-of-heredoc))
+		  'noerror (regexp-quote tramp-end-of-heredoc))
+		 (progn
+		   (tramp-message
+		    vec 2 "Could not retrieve `tramp-own-remote-path'")
+		   nil)))))
+
+	;; Replace place holder `tramp-default-remote-path'.
+	(when elt1
+	  (setcdr elt1
+		  (append
+                   (split-string (or default-remote-path "") ":" 'omit)
+		   (cdr elt1)))
+	  (setq remote-path (delq 'tramp-default-remote-path remote-path)))
+
+	;; Replace place holder `tramp-own-remote-path'.
+	(when elt2
+	  (setcdr elt2
+		  (append
+                   (split-string (or own-remote-path "") ":" 'omit)
+		   (cdr elt2)))
+	  (setq remote-path (delq 'tramp-own-remote-path remote-path)))
+
+	;; Remove double entries.
+	(setq elt1 remote-path)
+	(while (consp elt1)
+	  (while (and (car elt1) (setq elt2 (member (car elt1) (cdr elt1))))
+	    (setcar elt2 nil))
+	  (setq elt1 (cdr elt1)))
+
+	;; Remove non-existing directories.
+	(delq
+	 nil
+	 (mapcar
+	  (lambda (x)
+	    (and
+	     (stringp x)
+	     (file-directory-p (tramp-make-tramp-file-name vec x 'nohop))
+	     x))
+	  remote-path))))))
 
 (defun tramp-get-remote-locale (vec)
   "Determine remote locale, supporting UTF8 if possible."