From 27264bb9d93e24c8c1c8a8eae54b0828d1bd57f4 Mon Sep 17 00:00:00 2001
From: nightwing <amirjanyan@gmail.com>
Date: Thu, 20 Nov 2014 23:01:53 +0400
Subject: [PATCH] fix infinite loop when inserting more than 0xF000 lines at
 once

---
 lib/ace/document.js      | 36 ++++++++++++++++++++++++------------
 lib/ace/document_test.js | 19 +++++++++++++++++++
 2 files changed, 43 insertions(+), 12 deletions(-)

diff --git a/lib/ace/document.js b/lib/ace/document.js
index e92aa969..9207b3f5 100644
--- a/lib/ace/document.js
+++ b/lib/ace/document.js
@@ -575,14 +575,14 @@ var Document = function(textOrLines) {
             return;
         
         if (isInsert && delta.lines.length > 0xF000)
-            this.$splitAndapplyLargeDelta(delta);
+            this.$splitAndapplyLargeDelta(delta, 0xF000);
         
         // Apply.
         applyDelta(this.$lines, delta, doNotValidate);
         this._signal("change", delta);
     };
     
-    this.$splitAndapplyLargeDelta = function(delta) {
+    this.$splitAndapplyLargeDelta = function(delta, MAX) {
         // Split large insert deltas. This is necessary because:
         //    1. We need to support splicing delta lines into the document via $lines.splice.apply(...)
         //    2. fn.apply() doesn't work for a large number of params. The smallest threshold is on safari 0xFFFF.
@@ -592,18 +592,30 @@ var Document = function(textOrLines) {
         //        delta handling is too slow. If we make delete delta handling faster we can split all large deltas
         //        as shown in https://gist.github.com/aldendaniels/8367109#file-document-snippet-js
         //        If we do this, update validateDelta() to limit the number of lines in a delete delta.
-        while (delta.lines.length > 0xF000) {
-            // Get split deltas.
-            var lines = delta.lines.splice(0, 0xF000);
-            lines.push("");
-            var start = delta.start;
+        var lines = delta.lines;
+        var l = lines.length;
+        var row = delta.start.row; 
+        var column = delta.start.column;
+        var from = 0, to = 0;
+        do {
+            from = to;
+            to += MAX - 1;
+            var chunk = lines.slice(from, to);
+            if (to > l) {
+                // Update remaining delta.
+                delta.lines = chunk;
+                delta.start.row = row + from;
+                delta.start.column = column;
+                break;
+            }
+            chunk.push("");
             this.applyDelta({
-                start: this.pos(start.row, start.column),
-                end: this.pos(start.row += 0xF000, start.column = 0), // Updates remaining delta.
+                start: this.pos(row + from, column),
+                end: this.pos(row + to, column = 0),
                 action: delta.action,
-                lines: lines
+                lines: chunk
             }, true);
-        }
+        } while(true);
     };
     
     /**
@@ -615,7 +627,7 @@ var Document = function(textOrLines) {
         this.applyDelta({
             start: range.start,
             end: range.end,
-            action: delta.action == "insert" ? "remove" : "insert",
+            action: (delta.action == "insert" ? "remove" : "insert"),
             lines: delta.lines.slice()
         });
     };
diff --git a/lib/ace/document_test.js b/lib/ace/document_test.js
index ee27f00b..d7cc7ccb 100644
--- a/lib/ace/document_test.js
+++ b/lib/ace/document_test.js
@@ -296,6 +296,25 @@ module.exports = {
     "test: empty document has to contain one line": function() {
         var doc = new Document("");
         assert.equal(doc.$lines.length, 1);
+    },
+    
+    "test: inserting huge delta": function() {
+        var doc = new Document("");
+        var val = "";
+        var MAX = 0xF000;
+        for (var i = 0; i < 10 * MAX; i++) {
+            val += i + "\n"
+        }
+        doc.setValue(val);
+        assert.equal(doc.getValue(), val);
+        
+        for (var i = 3 * MAX + 2; i >= 3 * MAX - 2; i--) {
+            val = doc.getLines(0, i).join("\n");
+            doc.setValue("\nab");
+            assert.equal(doc.getValue(), "\nab");
+            doc.insert({row: 1, column: 1}, val);
+            assert.equal(doc.getValue(), "\na" + val + "b");
+        }
     }
 };