From e3518c29b1a9ea07748a713e12a3dd49e9af491d Mon Sep 17 00:00:00 2001
From: Jonathan Puckey <me@jonathanpuckey.com>
Date: Sat, 6 Oct 2012 13:08:07 +0200
Subject: [PATCH] Fix issue where adding the children of one group to another
 using Item#insertChildren / Item#addChildren does not work.

This fixes #119. To avoid duplication I chose to call
Item#insertChildren from Item#addChildren.
---
 src/item/Item.js    |  7 +++++--
 test/tests/Group.js | 18 ++++++++++++++++++
 2 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/src/item/Item.js b/src/item/Item.js
index d3a2b99d..51c8688b 100644
--- a/src/item/Item.js
+++ b/src/item/Item.js
@@ -1143,8 +1143,7 @@ function(name) {
 	 * @param {item[]} items The items to be added as children
 	 */
 	addChildren: function(items) {
-		for (var i = 0, l = items && items.length; i < l; i++)
-			this.insertChild(undefined, items[i]);
+		this.insertChildren(this._children.length, items);
 	},
 
 	/**
@@ -1156,6 +1155,10 @@ function(name) {
 	 * @param {Item[]} items The items to be appended as children
 	 */
 	insertChildren: function(index, items) {
+		// We need to clone items because it might be
+		// an Item#children array. Use Array.prototype.slice because
+		// in certain cases items is an arguments object
+		items = items && Array.prototype.slice.apply(items);
 		for (var i = 0, l = items && items.length; i < l; i++) {
 			if (this.insertChild(index, items[i]))
 				index++;
diff --git a/test/tests/Group.js b/test/tests/Group.js
index 413d134a..5dc66c0f 100644
--- a/test/tests/Group.js
+++ b/test/tests/Group.js
@@ -70,4 +70,22 @@ test('group.addChildren(otherGroup.children)', function() {
 	equals(function() {
 		return group.children.length;
 	}, 0);
+});
+
+test('group.insertChildren(0, otherGroup.children)', function() {
+	var group = new Group();
+	group.addChild(new Path());
+	group.addChild(new Path());
+	equals(function() {
+		return group.children.length;
+	}, 2);
+
+	var secondGroup = new Group();
+	secondGroup.insertChildren(0, group.children);
+	equals(function() {
+		return secondGroup.children.length;
+	}, 2);
+	equals(function() {
+		return group.children.length;
+	}, 0);
 });
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