From c998149b40c3eabb278dd9793503403f3a855a12 Mon Sep 17 00:00:00 2001
From: Ken Manheimer <ken.manheimer@gmail.com>
Date: Sat, 16 Jan 2016 14:16:22 -0500
Subject: [PATCH] multishell - prevent multiple history entries for the same
 name.

We probably can organize our maintenance of the history to coordinate
with completion's parallel maintenance, but for now we're going quick
and dirty.
---
 multishell.el | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/multishell.el b/multishell.el
index bb713db97..1fb32e56f 100644
--- a/multishell.el
+++ b/multishell.el
@@ -140,18 +140,20 @@ current-buffer behavior.)"
 (defun multishell-register-name-to-path (name path)
   "Add or replace entry associating NAME with PATH in `multishell-history'."
   ;; Add or promote to the front, tracking path changes in the process.
-  (let* ((entry (multishell-history-entry name))
+  (let* ((entries (multishell-history-entries name))
          (becomes (concat name path)))
-    (when entry
+    (dolist (entry entries)
       (setq multishell-history (delete entry multishell-history)))
-    (push becomes multishell-history)))
+    (setq multishell-history (push becomes multishell-history))))
 
-(defun multishell-history-entry (name)
+(defun multishell-history-entries (name)
   "Return `multishell-history' entry that starts with NAME, or nil if none."
-  (let ((match-expr (concat "^" name "\\\(/.*$\\\)?")))
+  (let ((match-expr (concat "^" name "\\\(/.*$\\\)?"))
+        got)
     (dolist (entry multishell-history)
       (when (string-match match-expr entry)
-        (return entry)))))
+        (setq got (cons entry got))))
+    got))
 
 (defun multishell-pop-to-shell (&optional arg)
   "Easily navigate to and within multiple shell buffers, local and remote.
@@ -329,7 +331,7 @@ customize the savehist group to activate savehist."
   ;; activity.  kill-buffer happens behind the scenes a whole lot.)
   (condition-case anyerr
       (let ((entry (and (derived-mode-p 'shell-mode)
-                        (multishell-history-entry
+                        (multishell-history-entries
                          (multishell-unbracket-asterisks (buffer-name))))))
         (when (and entry
                    (y-or-n-p (format "Remove multishell history entry `%s'? "
@@ -369,7 +371,7 @@ on empty input."
                              (and (with-current-buffer buffer
                                     ;; Shell mode buffers.
                                     (derived-mode-p 'shell-mode))
-                                  (not (multishell-history-entry name))
+                                  (not (multishell-history-entries name))
                                   name)))
                          (buffer-list)))
            multishell-history))
-- 
2.39.2