[elpa] externals/idlwave 8b462f73d9 256/360: Let arrows work correctly if no process in *idl*

[ELPA Syncer]

branch: externals/idlwave
commit 8b462f73d9ed45dd3427e863d485a86f668fc9cc
Author: JD Smith <jdtsmith@gmail.com>
Commit: JD Smith <jdtsmith@gmail.com>

    Let arrows work correctly if no process in *idl*
---
 idlw-shell.el | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/idlw-shell.el b/idlw-shell.el
index 332616fc98..7ee3f3b74c 100644
--- a/idlw-shell.el
+++ b/idlw-shell.el
@@ -1472,12 +1472,14 @@ when the IDL prompt gets displayed again after the 
current IDL command."
   "When in last line of process buffer, do `comint-previous-input'.
 Otherwise just move the line.  Move down unless UP is non-nil.
 Move normally inside of blocks, unless NOBLOCK-MOVE is non-nil."
-  (let* ((proc-pos (marker-position
-                   (process-mark (get-buffer-process (current-buffer)))))
+  (let* ((proc (get-buffer-process (current-buffer)))
+        (proc-pos (if proc (marker-position (process-mark proc))))
         (arg (or arg 1))
         (arg (if up arg (- arg))))
+    
     (if (eq t idlwave-shell-arrows-do-history) (goto-char proc-pos))
-    (if (and idlwave-shell-arrows-do-history
+    (if (and proc
+            idlwave-shell-arrows-do-history
             (or noblock-move
                 (if up
                     (= (line-number-at-pos) (line-number-at-pos proc-pos))