Fix shell-for/backward-command to exclude spaces

* lisp/shell.el (shell-forward-command, shell-backward-command):
  Handle the 'move case from re-search-forward/backward.

  fixes debbugs:20873

1 files changed, 15 insertions, 10 deletions

diff --git a/lisp/shell.el b/lisp/shell.el
index f71d1407a49..f5cb3215a0a 100644
--- a/lisp/shell.el
+++ b/lisp/shell.el
@@ -83,8 +83,8 @@
 ;; tab     completion-at-point          Complete filename/command/history
 ;; m-?     comint-dynamic-list-filename-completions
 ;;                                      List completions in help buffer
-;; m-c-f   shell-forward-command        Forward a shell command
-;; m-c-b   shell-backward-command       Backward a shell command
+;; c-c c-f shell-forward-command        Forward a shell command
+;; c-c c-b shell-backward-command       Backward a shell command
 ;;         dirs                         Resync the buffer's dir stack
 ;;         shell-dirtrack-mode          Turn dir tracking on/off
 ;;         comint-strip-ctrl-m          Remove trailing ^Ms from output
@@ -1092,10 +1092,12 @@ Copy Shell environment variable to Emacs: ")))
   "Move forward across ARG shell command(s).  Does not cross lines.
 See `shell-command-regexp'."
   (interactive "p")
-  (let ((limit (line-end-position)))
-    (if (re-search-forward (concat shell-command-regexp "\\([;&|][\t ]*\\)+")
-                           limit 'move arg)
-        (skip-syntax-backward " "))))
+  (let ((limit (line-end-position))
+        (pt (point)))
+    (re-search-forward (concat shell-command-regexp "\\([;&|][\t ]*\\)+")
+                       limit 'move arg)
+    (and (/= pt (point))
+         (skip-syntax-backward " " pt))))
 
 
 (defun shell-backward-command (&optional arg)
@@ -1106,10 +1108,13 @@ See `shell-command-regexp'."
     (when (> limit (point))
       (setq limit (line-beginning-position)))
     (skip-syntax-backward " " limit)
-    (if (re-search-backward
-         (format "[;&|]+[\t ]*\\(%s\\)" shell-command-regexp) limit 'move arg)
-        (progn (goto-char (match-beginning 1))
-               (skip-chars-forward ";&|")))))
+    (let ((pt (point)))
+      (if (re-search-backward
+           (format "[;&|]+[\t ]*\\(%s\\)" shell-command-regexp) limit 'move arg)
+          (progn (goto-char (match-beginning 1))
+                 (skip-chars-forward ";&|")))
+      (and (/= pt (point))
+           (skip-syntax-forward " " pt)))))
 
 (defun shell-dynamic-complete-command ()
   "Dynamically complete the command at point.