From 19d74ecfff802694c5170bdf0574e2771bb28322 Mon Sep 17 00:00:00 2001
From: Kris Maglione <maglione.k@gmail.com>
Date: Tue, 25 Oct 2011 21:14:21 -0400
Subject: [PATCH] Fix bug.

---
 common/content/commandline.js | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/common/content/commandline.js b/common/content/commandline.js
index bc1b0e56..c535e812 100644
--- a/common/content/commandline.js
+++ b/common/content/commandline.js
@@ -441,7 +441,12 @@ var CommandExMode = Class("CommandExMode", CommandMode, {
     prompt: ["Normal", ":"],
 
     complete: function CEM_complete(context) {
-        context.fork("ex", 0, completion, "ex");
+        try {
+            context.fork("ex", 0, completion, "ex");
+        }
+        catch (e) {
+            context.message = _("error.error", e);
+        }
     },
 
     onSubmit: function CEM_onSubmit(command) {
@@ -945,7 +950,7 @@ var CommandLine = Module("commandline", {
             dactyl.trapErrors(function () {
                 this.store.push({ value: str, timestamp: Date.now()*1000, privateData: this.checkPrivate(str) });
             }, this);
-            this.store = this.store.slice(this.store.length - options["history"]);
+            this.store = this.store.slice(Math.max(0, this.store.length - options["history"]));
         },
         /**
          * @property {function} Returns whether a data item should be