From eec012b24e8a39fef32631aab509d7e363f296ab Mon Sep 17 00:00:00 2001
From: nightwing <amirjanyan@gmail.com>
Date: Thu, 20 Nov 2014 23:28:09 +0400
Subject: [PATCH] fix ignoring empty delta

---
 lib/ace/document.js      |  2 +-
 lib/ace/document_test.js | 10 ++++++++++
 lib/ace/worker/mirror.js |  8 ++++----
 3 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/lib/ace/document.js b/lib/ace/document.js
index a06e3e33..cc72bc63 100644
--- a/lib/ace/document.js
+++ b/lib/ace/document.js
@@ -570,7 +570,7 @@ var Document = function(textOrLines) {
     this.applyDelta = function(delta, doNotValidate) {
         var isInsert = delta.action == "insert";
         // An empty range is a NOOP.
-        if (isInsert ? !delta.lines.length
+        if (isInsert ? delta.lines.length <= 1 && !delta.lines[0]
             : !Range.comparePoints(delta.start, delta.end))
             return;
         
diff --git a/lib/ace/document_test.js b/lib/ace/document_test.js
index d7cc7ccb..ada56cd2 100644
--- a/lib/ace/document_test.js
+++ b/lib/ace/document_test.js
@@ -298,6 +298,16 @@ module.exports = {
         assert.equal(doc.$lines.length, 1);
     },
     
+    "test: ignore empty delta": function() {
+        var doc = new Document("");
+        doc.on("change", function() {
+            throw "should ignore empty delta";
+        })
+        doc.insert({row: 0, column: 0}, "");
+        doc.insert({row: 1, column: 1}, "");
+        doc.remove({start: {row: 1, column: 1}, end: {row: 1, column: 1}});
+    },
+    
     "test: inserting huge delta": function() {
         var doc = new Document("");
         var val = "";
diff --git a/lib/ace/worker/mirror.js b/lib/ace/worker/mirror.js
index 514d377f..ef6e2aa3 100644
--- a/lib/ace/worker/mirror.js
+++ b/lib/ace/worker/mirror.js
@@ -18,11 +18,11 @@ var Mirror = exports.Mirror = function(sender) {
             doc.applyDeltas(data);
         } else {
             for (var i = 0; i < data.length; i += 2) {
-                if (Array.isArray(data[i+1]))
+                if (Array.isArray(data[i+1])) {
                     var d = {action: "insert", start: data[i], lines: data[i+1]};
-                else
-                    var d = {action: "remove", start: data[i],end: data[i+1]};
-                
+                } else {
+                    var d = {action: "remove", start: data[i], end: data[i+1]};
+                }
                 doc.applyDelta(d, true);
             }
         }