From 68a6a14d909f58e84b58199f6c8a267f49883a21 Mon Sep 17 00:00:00 2001
From: nightwing <amirjanyan@gmail.com>
Date: Sun, 3 May 2015 14:55:08 +0400
Subject: [PATCH] fix clearUndo

---
 plugins/c9.ide.editors/undomanager.js      | 15 +++++++--------
 plugins/c9.ide.editors/undomanager_test.js |  2 +-
 2 files changed, 8 insertions(+), 9 deletions(-)

diff --git a/plugins/c9.ide.editors/undomanager.js b/plugins/c9.ide.editors/undomanager.js
index 6ab1adc9..6560de05 100644
--- a/plugins/c9.ide.editors/undomanager.js
+++ b/plugins/c9.ide.editors/undomanager.js
@@ -10,7 +10,7 @@ define(function(require, module, exports) {
             var plugin = new Plugin("Ajax.org", main.consumes);
             var emit = plugin.getEmitter();
             
-            var position = -1, mark = null, stack = [];
+            var position = -1, mark = -2, stack = [];
 
             if (options)
                 setState(options);
@@ -55,7 +55,7 @@ define(function(require, module, exports) {
                 position = 0;
                 
                 if (mark < position)
-                    mark = -1;
+                    mark = -2;
                 
                 emit("change");
             }
@@ -64,7 +64,7 @@ define(function(require, module, exports) {
                 stack = stack.slice(0, position + 1);
                 
                 if (mark > position)
-                    mark = -1;
+                    mark = -2;
                 
                 if (!noEvent)
                     emit("change");
@@ -91,7 +91,7 @@ define(function(require, module, exports) {
                     position--;
                 
                 if (mark == idx)
-                    mark = -1;
+                    mark = -2;
                 else if (mark > idx)
                     mark--;
                 
@@ -105,8 +105,7 @@ define(function(require, module, exports) {
             }
             
             function isAtBookmark(){
-                return mark !== null && mark == position 
-                    || mark === null && position == -1;
+                return mark == position;
             }
             
             function item(idx) {
@@ -133,7 +132,7 @@ define(function(require, module, exports) {
                     return; // guard against broken stack 
                 stack = state.stack;
                 
-                emit("change"); //If you remove this again, change the test
+                emit("change"); // If you remove this again, change the test
             }
             
             function findItem(compressedItem) {
@@ -146,7 +145,7 @@ define(function(require, module, exports) {
 
                 position = -1;
                 stack = [];
-                mark = null;
+                mark = -1;
                 
                 emit("change");
             }
diff --git a/plugins/c9.ide.editors/undomanager_test.js b/plugins/c9.ide.editors/undomanager_test.js
index b7624924..a3c57ada 100644
--- a/plugins/c9.ide.editors/undomanager_test.js
+++ b/plugins/c9.ide.editors/undomanager_test.js
@@ -133,7 +133,7 @@ require(["lib/architect/architect", "lib/chai/chai"], function (architect, chai)
                 expect(undo.position).to.equal(4);
                 undo.undo(); check++;
                 
-                undo.setState({ position : -1, stack : stack, mark : null }); check++;
+                undo.setState({ position : -1, stack : stack, mark : -1 }); check++;
                 expect(undo.isAtBookmark()).to.equal(true);
                 expect(data).to.deep.equal(["a", "q"]);
                 checkCount();