editor: status bar
[fnpeditor.git] / src / smartxml / smartxml.test.js
index 0826458..5d1ca3e 100644 (file)
@@ -1,12 +1,13 @@
 define([
     'libs/chai',
     'libs/sinon',
+    'libs/underscore',
     './smartxml.js'
-], function(chai, sinon, smartxml) {
+], function(chai, sinon, _, smartxml) {
     
 'use strict';
 /*jshint expr:true */
-/* global describe, it, beforeEach */
+/* global describe, it, beforeEach, Node, DOMParser */
 
 var expect = chai.expect;
 
@@ -40,6 +41,93 @@ describe('smartxml', function() {
             doc.loadXML('<header></header>');
             expect(doc.root.getTagName()).to.equal('header');
         });
+
+        it('knows if it contains an ElementNode in its tree', function() {
+            var doc = getDocumentFromXML('<root><a></a>text</root>'),
+                root = doc.root,
+                a = root.contents()[0],
+                text = root.contents()[1];
+
+            expect(doc.containsNode(root)).to.equal(true, 'contains its root');
+            expect(doc.containsNode(a)).to.equal(true, 'contains Element Node');
+            expect(doc.containsNode(text)).to.equal(true, 'contains Text Node');
+        });
+
+        it('creates text nodes', function() {
+            var doc = getDocumentFromXML('<div></div>'),
+                emptyTextNode = doc.createDocumentNode({text:''}),
+                nonEmptyTextNode = doc.createDocumentNode({text: 'alice'});
+            expect(emptyTextNode.getText()).to.equal('', 'empty ok');
+            expect(nonEmptyTextNode.getText()).to.equal('alice', 'non empty ok');
+        });
+
+        it('creates nodes from xml strings', function() {
+            var doc = getDocumentFromXML('<div></div>'),
+                node = doc.createDocumentNode('<a>Alice<b></b></a>');
+            expect(node.getTagName()).to.equal('a');
+            expect(node.contents().length).to.equal(2);
+            expect(node.contents()[0].getText()).to.equal('Alice');
+            expect(node.contents()[1].getTagName()).to.equal('b');
+        });
+    });
+
+    describe('DocumentNode', function() {
+        it('can be cloned', function() {
+            var doc = getDocumentFromXML('<div>Alice</div>'),
+                text = doc.root.contents()[0],
+                clone, suffix;
+
+            [doc.root, text].forEach(function(node) {
+                suffix = ' (' + (node.nodeType === Node.TEXT_NODE ? 'text' : 'element')  + ')';
+                clone = node.clone();
+                expect(doc.containsNode(clone)).to.equal(false, 'clone is not contained in a document' + suffix);
+                expect(node.sameNode(clone)).to.equal(false, 'clone is not same node as its originator' + suffix);
+                expect(node.nativeNode.isEqualNode(clone.nativeNode)).to.equal(true, 'clone is identical as its originator' + suffix);
+            });
+        });
+
+        it('can be cloned with its contents and its contents data', function() {
+            var doc = getDocumentFromXML('<root><div></div></root>'),
+                root = doc.root,
+                div = root.contents()[0];
+
+            var ClonableObject = function(arg) {
+                this.arg = arg;
+            };
+            ClonableObject.prototype.clone = function() {
+                return new ClonableObject(this.arg);
+            };
+
+            div.setData('key', 'value');
+            div.setData('clonableObject', new ClonableObject('test'));
+
+            var rootClone = root.clone(),
+                divClone = rootClone.contents()[0],
+                stringClone = divClone.getData('key'),
+                objClone = divClone.getData('clonableObject');
+
+            expect(stringClone).to.equal('value');
+            expect(objClone.arg).to.equal('test', 'clonable object got copied');
+            expect(objClone !== div.getData('clonableObject')).to.be.equal(true, 'copy of the clonable object is a new object');
+        });
+
+        it('knows its path in the document tree', function() {
+            var doc = getDocumentFromXML('<root><a><b><c></c>text</b></a></root>'),
+                root = doc.root,
+                a = root.contents()[0],
+                b = a.contents()[0],
+                text = b.contents()[1];
+
+            expect(root.getPath()).to.eql([], 'path of the root element is empty');
+            expect(a.getPath()).to.eql([0]);
+            expect(b.getPath()).to.eql([0, 0]);
+            expect(text.getPath()).to.eql([0,0,1]);
+
+            /* Paths relative to a given ancestor */
+            expect(text.getPath(root)).to.eql([0,0,1]);
+            expect(text.getPath(a)).to.eql([0,1]);
+            expect(text.getPath(b)).to.eql([1]);
+        });
     });
 
     describe('Basic ElementNode properties', function() {
@@ -81,40 +169,16 @@ describe('smartxml', function() {
 
             it('can change tag name', function() {
                 var node = elementNodeFromXML('<div></div>');
-                node.setTag('span');
+                node = node.setTag('span');
                 expect(node.getTagName()).to.equal('span');
             });
 
-            it('emits nodeTagChange event', function() {
-                var node = elementNodeFromXML('<div></div>'),
-                    spy = sinon.spy();
-
-                node.document.on('change', spy);
-                node.setTag('span');
-                var event = spy.args[0][0];
-
-                expect(event.type).to.equal('nodeTagChange');
-                expect(event.meta.node.sameNode(node)).to.be.true;
-                expect(event.meta.oldTagName).to.equal('div');
-            });
-
             describe('Implementation specific expectations', function() {
-                // DOM specifies ElementNode tag as a read-only property, so
-                // changing it in a seamless way is a little bit tricky. For this reason
-                // the folowing expectations are required, despite the fact that they actually are
-                // motivated by implemetation details.
-
-                it('keeps node in the document', function() {
-                    var doc = getDocumentFromXML('<div><header></header></div>'),
-                        header = doc.root.contents()[0];
-                    header.setTag('span');
-                    expect(header.parent().sameNode(doc.root)).to.be.true;
-                });
                 it('keeps custom data', function() {
                     var node = elementNodeFromXML('<div></div>');
 
                     node.setData('key', 'value');
-                    node.setTag('header');
+                    node = node.setTag('header');
                     
                     expect(node.getTagName()).to.equal('header');
                     expect(node.getData()).to.eql({key: 'value'});
@@ -126,12 +190,13 @@ describe('smartxml', function() {
                     expect(doc.root.getTagName()).to.equal('span');
                 });
 
-                it('keeps contents', function() {
+                it('keeps node contents', function() {
                     var node = elementNodeFromXML('<div><div></div></div>');
-                    node.setTag('header');
+                    node = node.setTag('header');
                     expect(node.contents()).to.have.length(1);
                 });
             });
+        });
 
         describe('Setting node attributes', function() {
             it('can set node attribute', function() {
@@ -154,8 +219,6 @@ describe('smartxml', function() {
                 expect(event.meta.oldVal).to.equal('value1');
             });
         });
-
-        });
     });
 
     describe('Basic TextNode properties', function() {
@@ -247,10 +310,118 @@ describe('smartxml', function() {
             });
         });
 
+        describe('Dividing text node into two with element node', function() {
+                it('can divide text node with element node, splitting text node into two', function() {
+                    var doc = getDocumentFromXML('<div>Alice has a cat</div>'),
+                        text = doc.root.contents()[0];
+
+                    var returned = text.divideWithElementNode({tagName: 'aside'}, {offset: 5}),
+                        contents = doc.root.contents(),
+                        lhsText = contents[0],
+                        rhsText = contents[2];
+
+                    expect(lhsText.getText()).to.equal('Alice');
+                    expect(returned.sameNode(contents[1]));
+                    expect(rhsText.getText()).to.equal(' has a cat');
+                });
+
+                it('treats dividing at the very end as appending after it', function() {
+                    var doc = getDocumentFromXML('<div>Alice has a cat</div>'),
+                        text = doc.root.contents()[0];
+
+
+                    var returned = text.divideWithElementNode({tagName: 'aside'}, {offset: 15}),
+                        contents = doc.root.contents(),
+                        textNode = contents[0],
+                        elementNode = contents[1];
+
+                    expect(contents.length).to.equal(2);
+                    expect(textNode.getText()).to.equal('Alice has a cat');
+                    expect(returned.sameNode(elementNode)).to.be.true;
+                    expect(elementNode.getTagName()).to.equal('aside');
+                });
+
+                it('treats dividing at the very beginning as prepending before it', function() {
+                    var doc = getDocumentFromXML('<div>Alice has a cat</div>'),
+                        text = doc.root.contents()[0];
+
+                    var returned = text.divideWithElementNode({tagName: 'aside'}, {offset: 0}),
+                        contents = doc.root.contents(),
+                        textNode = contents[1],
+                        elementNode = contents[0];
+
+                    expect(contents.length).to.equal(2);
+                    expect(textNode.getText()).to.equal('Alice has a cat');
+                    expect(returned.sameNode(elementNode)).to.be.true;
+                    expect(elementNode.getTagName()).to.equal('aside');
+                });
+        });
     });
 
     describe('Manipulations', function() {
 
+        describe('detaching nodes', function() {
+            it('can detach document root node', function() {
+                var doc = getDocumentFromXML('<div></div>');
+
+                doc.root.detach();
+                expect(doc.root).to.equal(null);
+            });
+        });
+
+        describe('replacing node with another one', function() {
+            it('replaces node with another one', function() {
+                var doc = getDocumentFromXML('<div><a></a></div>'),
+                    a = doc.root.contents()[0];
+
+                var c = a.replaceWith({tagName: 'b', attrs: {b:'1'}});
+
+                expect(doc.root.contents()[0].sameNode(c));
+                expect(c.getTagName()).to.equal('b');
+                expect(c.getAttr('b')).to.equal('1');
+            });
+            it('can replace document root', function() {
+                var doc = getDocumentFromXML('<div></div>');
+
+                var header = doc.root.replaceWith({tagName: 'header'});
+
+                expect(doc.root.sameNode(header)).to.be.true;
+                expect(doc.containsNode(header)).to.be.true;
+            });
+        });
+
+        it('merges adjacent text nodes resulting from detaching an element node in between', function() {
+            var doc = getDocumentFromXML('<div>Alice <span>has</span>a cat</div>'),
+                span = doc.root.contents()[1];
+
+            span.detach();
+
+            var rootContents = doc.root.contents();
+            expect(rootContents).to.have.length(1, 'one child left');
+            expect(rootContents[0].getText()).to.equal('Alice a cat');
+        });
+
+        it('inserts node at index', function() {
+            var doc = getDocumentFromXML('<div><a></a><b></b><c></c></div>'),
+                b = doc.root.contents()[1];
+
+            var inserted = doc.root.insertAtIndex({tagName: 'test'}, 1);
+
+            expect(doc.root.contents()[1].sameNode(inserted)).to.equal(true, 'inserted node returned');
+            expect(b.getIndex()).to.equal(2, 'b node shifted right');
+        });
+
+        it('appends node when inserting node at index out of range', function() {
+            var doc = getDocumentFromXML('<div></div>');
+
+            var test1 = doc.root.insertAtIndex({tagName: 'test1'}, 0),
+                test2 = doc.root.insertAtIndex({tagName: 'test1'}, 10);
+
+            expect(doc.root.contents()[0].sameNode(test1)).to.equal(true, 'inserting at index 0 of empty nodes appends node');
+            expect(doc.root.contents().length).to.equal(1, 'inserting at index out of range does nothing');
+            expect(test2).to.equal(undefined, 'inserting at index out of range returns undefined');
+        });
+
         it('appends element node to another element node', function() {
             var node1 = elementNodeFromParams({tag: 'div'}),
                 node2 = elementNodeFromParams({tag: 'a'}),
@@ -271,12 +442,95 @@ describe('smartxml', function() {
             expect(node1.contents()[1].sameNode(node2)).to.be.true;
         });
 
-        it('wraps element node with another element node', function() {
+        describe('adding text nodes', function() {
+            it('merges text nodes on append', function() {
+                var doc = getDocumentFromXML('<root>text1</root>'),
+                    returned;
+                returned = doc.root.append({text: 'text2'});
+                expect(doc.root.contents().length).to.equal(1);
+                expect(returned.sameNode(doc.root.contents()[0])).to.equal(true, 'modified node returned');
+                expect(doc.root.contents()[0].getText()).to.equal('text1text2');
+            });
+
+            it('merges text nodes on prepend', function() {
+                var doc = getDocumentFromXML('<root>text1</root>'),
+                    returned;
+                returned = doc.root.prepend({text: 'text2'});
+                expect(doc.root.contents().length).to.equal(1);
+                expect(returned.sameNode(doc.root.contents()[0])).to.equal(true, 'modified node returned');
+                expect(doc.root.contents()[0].getText()).to.equal('text2text1');
+            });
+
+            it('merges text nodes on before text node', function() {
+                var doc = getDocumentFromXML('<root>text1</root>'),
+                    textNode = doc.root.contents()[0],
+                    returned;
+                returned = textNode.before({text: 'text2'});
+                expect(doc.root.contents().length).to.equal(1);
+                expect(returned.sameNode(doc.root.contents()[0])).to.equal(true, 'modified node returned');
+                expect(doc.root.contents()[0].getText()).to.equal('text2text1');
+            });
+
+            it('merges text nodes on after text node', function() {
+                var doc = getDocumentFromXML('<root>text1</root>'),
+                    textNode = doc.root.contents()[0],
+                    returned;
+                returned = textNode.after({text: 'text2'});
+                expect(doc.root.contents().length).to.equal(1);
+                expect(returned.sameNode(doc.root.contents()[0])).to.equal(true, 'modified node returned');
+                expect(doc.root.contents()[0].getText()).to.equal('text1text2');
+            });
+
+            it('merges text nodes on before element node', function() {
+                var doc = getDocumentFromXML('<root>text1<div></div></root>'),
+                    textNode = doc.root.contents()[0],
+                    div = doc.root.contents()[1],
+                    returned;
+                returned = div.before({text: 'text2'});
+                expect(doc.root.contents().length).to.equal(2);
+                expect(returned.sameNode(doc.root.contents()[0])).to.equal(true, 'modified node returned');
+                expect(textNode.getText()).to.equal('text1text2');
+            });
+
+            it('merges text nodes on after element node', function() {
+                var doc = getDocumentFromXML('<root><div></div>text1</root>'),
+                    textNode = doc.root.contents()[1],
+                    div = doc.root.contents()[0],
+                    returned;
+                returned = div.after({text: 'text2'});
+                expect(doc.root.contents().length).to.equal(2);
+                expect(returned.sameNode(doc.root.contents()[1])).to.equal(true, 'modified node returned');
+                expect(textNode.getText()).to.equal('text2text1');
+            });
+        });
+
+        it('wraps root element node with another element node', function() {
             var node = elementNodeFromXML('<div></div>'),
                 wrapper = elementNodeFromXML('<wrapper></wrapper>');
 
             node.wrapWith(wrapper);
             expect(node.parent().sameNode(wrapper)).to.be.true;
+            expect(node.document.root.sameNode(wrapper)).to.be.true;
+        });
+
+        it('wraps element node with another element node', function() {
+            var doc = getDocumentFromXML('<section><div></div></section>'),
+                div = doc.root.contents()[0];
+
+            var wrapper = div.wrapWith({tagName: 'wrapper'});
+            expect(wrapper.sameNode(doc.root.contents()[0])).to.equal(true, '1');
+            expect(div.parent().sameNode(wrapper)).to.equal(true, '2');
+            expect(wrapper.contents()[0].sameNode(div)).to.equal(true, '3');
+        });
+
+        it('wraps element outside of document tree', function() {
+            var doc = getDocumentFromXML('<section><div></div></section>'),
+                node = doc.createDocumentNode({tagName: 'node'});
+
+            node.wrapWith({tagName: 'wrapper'});
+            expect(node.parent().getTagName()).to.equal('wrapper');
+            expect(node.parent().contents()[0].sameNode(node)).to.be.true;
+            expect(doc.root.getTagName()).to.equal('section');
         });
 
         it('unwraps element node contents', function() {
@@ -291,11 +545,37 @@ describe('smartxml', function() {
             expect(node.contents()[2].getText()).to.equal(' a cat!');
         });
 
+        it('unwrap single element node from its parent', function() {
+            var doc = getDocumentFromXML('<div><a><b></b></a></div>'),
+                div = doc.root,
+                a = div.contents()[0],
+                b = a.contents()[0];
+
+            var parent = b.unwrap();
+
+            expect(parent.sameNode(div)).to.equal(true, 'returns new parent');
+            expect(div.contents()).to.have.length(1, 'root contains only one node');
+            expect(div.contents()[0].sameNode(b)).to.equal(true, 'node got unwrapped');
+        });
+
+        it('unwrap single text node from its parent', function() {
+            var doc = getDocumentFromXML('<div>Some <span>text</span>!</div>'),
+                div = doc.root,
+                span = div.contents()[1],
+                text = span.contents()[0];
+
+            var parent = text.unwrap();
+
+            expect(parent.sameNode(div)).to.equal(true, 'returns new parent');
+            expect(div.contents()).to.have.length(1, 'root contains only one node');
+            expect(div.contents()[0].getText()).to.equal('Some text!');
+        });
+
         describe('Wrapping text', function() {
             it('wraps text spanning multiple sibling TextNodes', function() {
                 var section = elementNodeFromXML('<section>Alice has a <span>small</span> cat</section>'),
                     wrapper = section.wrapText({
-                        _with: {tag: 'span', attrs: {'attr1': 'value1'}},
+                        _with: {tagName: 'span', attrs: {'attr1': 'value1'}},
                         offsetStart: 6,
                         offsetEnd: 4,
                         textNodeIdx: [0,2]
@@ -307,6 +587,7 @@ describe('smartxml', function() {
 
                 var wrapper2 = section.contents()[1];
                 expect(wrapper2.sameNode(wrapper)).to.be.true;
+                expect(wrapper.getTagName()).to.equal('span');
 
                 var wrapperContents = wrapper.contents();
                 expect(wrapperContents.length).to.equal(3);
@@ -326,16 +607,16 @@ describe('smartxml', function() {
                     lastDiv = section.contents()[section.contents().length -1];
 
                 var returned = section.document.wrapNodes({
-                        element1: aliceText,
-                        element2: lastDiv,
+                        node1: aliceText,
+                        node2: lastDiv,
                         _with: {tagName: 'header'}
                     });
 
-                var sectionContents = section.contents(),
-                    header = sectionContents[0],
+                var sectionContentss = section.contents(),
+                    header = sectionContentss[0],
                     headerContents = header.contents();
 
-                expect(sectionContents).to.have.length(1);
+                expect(sectionContentss).to.have.length(1);
                 expect(header.sameNode(returned)).to.equal(true, 'wrapper returned');
                 expect(header.parent().sameNode(section)).to.be.true;
                 expect(headerContents).to.have.length(3);
@@ -350,16 +631,16 @@ describe('smartxml', function() {
                     div3 = section.contents()[2];
 
                 section.document.wrapNodes({
-                        element1: div2,
-                        element2: div3,
+                        node1: div2,
+                        node2: div3,
                         _with: {tagName: 'header'}
                     });
 
-                var sectionContents = section.contents(),
-                    header = sectionContents[1],
+                var sectionContentss = section.contents(),
+                    header = sectionContentss[1],
                     headerChildren = header.contents();
 
-                expect(sectionContents).to.have.length(3);
+                expect(sectionContentss).to.have.length(3);
                 expect(headerChildren).to.have.length(2);
                 expect(headerChildren[0].sameNode(div2)).to.equal(true, 'first node wrapped');
                 expect(headerChildren[1].sameNode(div3)).to.equal(true, 'second node wrapped');
@@ -368,6 +649,487 @@ describe('smartxml', function() {
 
     });
 
+    var getTextNodes = function(text, doc) {
+        /* globals Node */
+        var toret = [];
+        var search = function(node) {
+            node.contents().forEach(function(node) {
+                if(node.nodeType === Node.TEXT_NODE) {
+                    if(node.getText() === text) {
+                        toret.push(node);
+                    }
+                } else {
+                    search(node);
+                }
+            });
+        };
+        search(doc.root);
+        return toret;
+    };
+
+    var getTextNode = function(text, doc) {
+        var nodes = getTextNodes(text, doc),
+            error;
+        if(nodes.length === 0) {
+            error = 'Text not found';
+        } else if(nodes.length > 1) {
+            error = 'Text not unique';
+        } else if(nodes[0].getText() !== text) {
+            error = 'I was trying to cheat your test :(';
+        }
+        if(error) {
+            throw new Error(error);
+        }
+        return nodes[0];
+    };
+
+    describe('Removing arbitrary text', function() {
+        it('removes within single text element', function() {
+            var doc = getDocumentFromXML('<div>Alice</div>'),
+                text = getTextNode('Alice', doc);
+            doc.deleteText({
+                from: {
+                    node: text,
+                    offset: 1
+                },
+                to: {
+                    node: text,
+                    offset: 4
+                }
+            });
+            expect(doc.root.contents().length).to.equal(1);
+            expect(doc.root.contents()[0].getText()).to.equal('Ae');
+        });
+        it('removes across elements - 1', function() {
+            var doc = getDocumentFromXML('<div><a>aaa</a><b>bbb</b></div>');
+
+            doc.deleteText({
+                from: {
+                    node: getTextNode('aaa', doc),
+                    offset: 2
+                },
+                to: {
+                    node: getTextNode('bbb', doc),
+                    offset: 2
+                }
+            });
+
+            var contents = doc.root.contents();
+            expect(contents.length).to.equal(2);
+            expect(contents[0].contents()[0].getText()).to.equal('aa');
+            expect(contents[1].contents()[0].getText()).to.equal('b');
+        });
+        it('removes across elements - 2', function() {
+            var doc = getDocumentFromXML('<a><b><c>ccc</c></b>xxx</a>');
+            doc.deleteText({
+                from: {
+                    node: getTextNode('ccc', doc),
+                    offset: 2
+                },
+                to: {
+                    node: getTextNode('xxx', doc),
+                    offset: 2
+                }
+            });
+
+            var contents = doc.root.contents();
+            expect(contents.length).to.equal(2);
+            expect(contents[0].getTagName()).to.equal('b');
+            expect(contents[1].getText()).to.equal('x');
+            
+            var bContents = contents[0].contents();
+            expect(bContents.length).to.equal(1);
+            expect(bContents[0].getTagName()).to.equal('c');
+            expect(bContents[0].contents().length).to.equal(1);
+            expect(bContents[0].contents()[0].getText()).to.equal('cc');
+        });
+        it('remove across elements - 3 (merged text nodes)', function() {
+            var doc = getDocumentFromXML('<div>Alice <span>has</span> a cat</div>');
+            doc.deleteText({
+                from: {
+                    node: getTextNode('Alice ', doc),
+                    offset: 1
+                },
+                to: {
+                    node: getTextNode(' a cat', doc),
+                    offset: 3
+                }
+            });
+            var contents = doc.root.contents();
+            expect(contents.length).to.equal(1);
+            expect(contents[0].getText()).to.equal('Acat');
+        });
+        it('remove across elements - 4', function() {
+            var doc = getDocumentFromXML('<div>Alice <div>has <span>a</span> cat</div></div>');
+            doc.deleteText({
+                from: {
+                    node: getTextNode('Alice ', doc),
+                    offset: 1
+                },
+                to: {
+                    node: getTextNode(' cat', doc),
+                    offset: 1
+                }
+            });
+            var contents = doc.root.contents();
+            expect(contents.length).to.equal(2);
+            expect(contents[0].getText()).to.equal('A');
+            expect(contents[1].getTagName()).to.equal('div');
+            expect(contents[1].contents().length).to.equal(1);
+            expect(contents[1].contents()[0].getText()).to.equal('cat');
+        });
+        it('removes across elements - 5 (whole document)', function() {
+            var doc = getDocumentFromXML('<div>Alice <div>has <span>a</span> cat</div>!!!</div>');
+            doc.deleteText({
+                from: {
+                    node: getTextNode('Alice ', doc),
+                    offset: 0
+                },
+                to: {
+                    node: getTextNode('!!!', doc),
+                    offset: 3
+                }
+            });
+
+            expect(doc.root.getTagName()).to.equal('div');
+            expect(doc.root.contents().length).to.equal(1);
+            expect(doc.root.contents()[0].getText()).to.equal('');
+        });
+        it('removes nodes in between', function() {
+            var doc = getDocumentFromXML('<div><a>aaa<x>!</x></a>xxx<x></x><b><x>!</x>bbb</b></div>');
+            doc.deleteText({
+                from: {
+                    node: getTextNode('aaa', doc),
+                    offset: 2
+                },
+                to: {
+                    node: getTextNode('bbb', doc),
+                    offset: 2
+                }
+            });
+
+            var contents = doc.root.contents();
+            expect(contents.length).to.equal(2, 'two nodes survived');
+            expect(contents[0].getTagName()).to.equal('a');
+            expect(contents[1].getTagName()).to.equal('b');
+            expect(contents[0].contents().length).to.equal(1);
+            expect(contents[0].contents()[0].getText()).to.equal('aa');
+            expect(contents[1].contents().length).to.equal(1);
+            expect(contents[1].contents()[0].getText()).to.equal('b');
+        });
+    });
+
+    describe('Splitting text', function() {
+    
+        it('splits TextNode\'s parent into two ElementNodes', function() {
+            var doc = getDocumentFromXML('<section><header>Some header</header></section>'),
+                section = doc.root,
+                text = section.contents()[0].contents()[0];
+
+            var returnedValue = text.split({offset: 5});
+            expect(section.contents().length).to.equal(2, 'section has two children');
+            
+            var header1 = section.contents()[0];
+            var header2 = section.contents()[1];
+
+            expect(header1.getTagName()).to.equal('header', 'first section child ok');
+            expect(header1.contents().length).to.equal(1, 'first header has one child');
+            expect(header1.contents()[0].getText()).to.equal('Some ', 'first header has correct content');
+            expect(header2.getTagName()).to.equal('header', 'second section child ok');
+            expect(header2.contents().length).to.equal(1, 'second header has one child');
+            expect(header2.contents()[0].getText()).to.equal('header', 'second header has correct content');
+
+            expect(returnedValue.first.sameNode(header1)).to.equal(true, 'first node returned');
+            expect(returnedValue.second.sameNode(header2)).to.equal(true, 'second node returned');
+        });
+
+        it('leaves empty copy of ElementNode if splitting at the very beginning', function() {
+                var doc = getDocumentFromXML('<section><header>Some header</header></section>'),
+                section = doc.root,
+                text = section.contents()[0].contents()[0];
+
+                text.split({offset: 0});
+                
+                var header1 = section.contents()[0];
+                var header2 = section.contents()[1];
+
+                expect(header1.contents().length).to.equal(0);
+                expect(header2.contents()[0].getText()).to.equal('Some header');
+        });
+
+        it('leaves empty copy of ElementNode if splitting at the very end', function() {
+                var doc = getDocumentFromXML('<section><header>Some header</header></section>'),
+                section = doc.root,
+                text = section.contents()[0].contents()[0];
+
+                text.split({offset: 11});
+                
+                var header1 = section.contents()[0];
+                var header2 = section.contents()[1];
+
+                expect(header1.contents()[0].getText()).to.equal('Some header');
+                expect(header2.contents().length).to.equal(0);
+        });
+
+        it('keeps TextNodes\'s parent\'s children elements intact', function() {
+            var doc = getDocumentFromXML('<section><header>A <span>fancy</span> and <span>nice</span> header</header></section>'),
+                section = doc.root,
+                header = section.contents()[0],
+                textAnd = header.contents()[2];
+
+            textAnd.split({offset: 2});
+            
+            var sectionContents = section.contents();
+            expect(sectionContents.length).to.equal(2, 'Section has two children');
+            expect(sectionContents[0].getTagName()).to.equal('header', 'First section node is a header');
+            expect(sectionContents[1].getTagName()).to.equal('header', 'Second section node is a header');
+
+            var firstHeaderContents = sectionContents[0].contents();
+            expect(firstHeaderContents.length).to.equal(3, 'First header has three children');
+            expect(firstHeaderContents[0].getText()).to.equal('A ', 'First header starts with a text');
+            expect(firstHeaderContents[1].getTagName()).to.equal('span', 'First header has span in the middle');
+            expect(firstHeaderContents[2].getText()).to.equal(' a', 'First header ends with text');
+
+            var secondHeaderContents = sectionContents[1].contents();
+            expect(secondHeaderContents.length).to.equal(3, 'Second header has three children');
+            expect(secondHeaderContents[0].getText()).to.equal('nd ', 'Second header starts with text');
+            expect(secondHeaderContents[1].getTagName()).to.equal('span', 'Second header has span in the middle');
+            expect(secondHeaderContents[2].getText()).to.equal(' header', 'Second header ends with text');
+        });
+    });
+
+    describe('Events', function() {
+        it('emits nodeDetached event on node detach', function() {
+            var node = elementNodeFromXML('<div><div></div></div>'),
+                innerNode = node.contents()[0],
+                spy = sinon.spy();
+            node.document.on('change', spy);
+            
+            var detached = innerNode.detach(),
+                event = spy.args[0][0];
+
+            expect(event.type).to.equal('nodeDetached');
+            expect(event.meta.node.sameNode(detached, 'detached node in event meta'));
+            expect(event.meta.parent.sameNode(node), 'original parent node in event meta');
+        }),
+
+        it('emits nodeAdded event when appending new node', function() {
+            var node = elementNodeFromXML('<div></div>'),
+                spy = sinon.spy();
+            node.document.on('change', spy);
+            
+            var appended = node.append({tagName:'div'}),
+                event = spy.args[0][0];
+            expect(event.type).to.equal('nodeAdded');
+            expect(event.meta.node.sameNode(appended)).to.be.true;
+        });
+        
+        it('emits nodeMoved when appending aready existing node', function() {
+            var node = elementNodeFromXML('<div><a></a><b></b></div>'),
+                a = node.contents()[0],
+                b = node.contents()[1],
+                spy = sinon.spy();
+            node.document.on('change', spy);
+            
+            var appended = a.append(b),
+                event = spy.args[0][0];
+
+            expect(spy.callCount).to.equal(1);
+            expect(event.type).to.equal('nodeMoved');
+            expect(event.meta.node.sameNode(appended)).to.be.true;
+            expect(node.document.root.sameNode(event.meta.parent)).to.equal(true, 'previous parent attached to event meta');
+        });
+        
+        it('emits nodeAdded event when prepending new node', function() {
+            var node = elementNodeFromXML('<div></div>'),
+                spy = sinon.spy();
+            node.document.on('change', spy);
+            
+            var prepended = node.prepend({tagName:'div'}),
+                event = spy.args[0][0];
+            expect(event.type).to.equal('nodeAdded');
+            expect(event.meta.node.sameNode(prepended)).to.be.true;
+        });
+        
+        it('emits nodeMoved when prepending aready existing node', function() {
+            var node = elementNodeFromXML('<div><a></a><b></b></div>'),
+                a = node.contents()[0],
+                b = node.contents()[1],
+                spy = sinon.spy();
+            node.document.on('change', spy);
+            
+            var prepended = a.prepend(b),
+                event = spy.args[0][0];
+            expect(spy.callCount).to.equal(1);
+            expect(event.type).to.equal('nodeMoved');
+            expect(event.meta.node.sameNode(prepended)).to.be.true;
+        });
+        
+        it('emits nodeAdded event when inserting node after another', function() {
+            var node = elementNodeFromXML('<div><a></a></div>').contents()[0],
+                spy = sinon.spy();
+            node.document.on('change', spy);
+            
+            var inserted = node.after({tagName:'div'}),
+                event = spy.args[0][0];
+            expect(event.type).to.equal('nodeAdded');
+            expect(event.meta.node.sameNode(inserted)).to.be.true;
+        });
+        
+        it('emits nodeMoved when inserting aready existing node after another', function() {
+            var node = elementNodeFromXML('<div><a></a><b></b></div>'),
+                a = node.contents()[0],
+                b = node.contents()[1],
+                spy = sinon.spy();
+            node.document.on('change', spy);
+            var inserted = b.after(a),
+                event = spy.args[0][0];
+
+            expect(spy.callCount).to.equal(1);
+            expect(event.type).to.equal('nodeMoved');
+            expect(event.meta.node.sameNode(inserted)).to.be.true;
+        });
+
+        it('emits nodeAdded event when inserting node before another', function() {
+            var node = elementNodeFromXML('<div><a></a></div>').contents()[0],
+                spy = sinon.spy();
+            node.document.on('change', spy);
+            
+            var inserted = node.before({tagName:'div'}),
+                event = spy.args[0][0];
+            expect(event.type).to.equal('nodeAdded');
+            expect(event.meta.node.sameNode(inserted)).to.be.true;
+        });
+        
+        it('emits nodeAdded when inserting aready existing node before another', function() {
+            var node = elementNodeFromXML('<div><a></a><b></b></div>'),
+                a = node.contents()[0],
+                b = node.contents()[1],
+                spy = sinon.spy();
+            node.document.on('change', spy);
+            var inserted = a.before(b),
+                event = spy.args[0][0];
+
+            expect(spy.callCount).to.equal(1);
+            expect(event.type).to.equal('nodeMoved');
+            expect(event.meta.node.sameNode(inserted)).to.be.true;
+        });
+
+        it('emits nodeDetached and nodeAdded when replacing root node with another', function() {
+            var doc = getDocumentFromXML('<a></a>'),
+                oldRoot = doc.root,
+                spy = sinon.spy();
+
+            doc.on('change', spy);
+
+            doc.root.replaceWith({tagName: 'b'});
+
+            expect(spy.callCount).to.equal(2);
+
+            var event1 = spy.args[0][0],
+                event2 = spy.args[1][0];
+
+            expect(event1.type).to.equal('nodeDetached');
+            expect(event1.meta.node.sameNode(oldRoot)).to.equal(true, 'root node in nodeDetached event metadata');
+            expect(event2.type).to.equal('nodeAdded');
+            expect(event2.meta.node.sameNode(doc.root)).to.equal(true, 'new root node in nodelAdded event meta');
+        });
+
+
+        ['append', 'prepend', 'before', 'after'].forEach(function(insertionMethod) {
+            it('emits nodeDetached for node moved from a document tree to out of document node ' + insertionMethod, function() {
+                var doc = getDocumentFromXML('<div><a></a></div>'),
+                    a = doc.root.contents()[0],
+                    spy = sinon.spy();
+
+                doc.on('change', spy);
+
+                var newNode = doc.createDocumentNode({tagName: 'b'}),
+                    newNodeInner = newNode.append({tagName:'c'});
+
+                newNodeInner[insertionMethod](a);
+
+                var event = spy.args[0][0];
+                expect(event.type).to.equal('nodeDetached');
+                expect(event.meta.node.sameNode(a));
+            });
+
+            it('doesn\'t emit nodeDetached event for already out of document node moved to out of document node' + insertionMethod, function() {
+                var doc = getDocumentFromXML('<div><a></a></div>'),
+                    spy = sinon.spy();
+
+                doc.on('change', spy);
+
+                var newNode = doc.createDocumentNode({tagName: 'b'});
+                newNode.append({tagName:'c'});
+
+                expect(spy.callCount).to.equal(0);
+            });
+        });
+
+
+    });
+
+    describe('Traversing', function() {
+        describe('Basic', function() {
+            it('can access node parent', function() {
+                var doc = getDocumentFromXML('<a><b></b></a>'),
+                    a = doc.root,
+                    b = a.contents()[0];
+
+                expect(a.parent()).to.equal(null, 'parent of a root is null');
+                expect(b.parent().sameNode(a)).to.be.true;
+            });
+            it('can access node parents', function() {
+                var doc = getDocumentFromXML('<a><b><c></c></b></a>'),
+                    a = doc.root,
+                    b = a.contents()[0],
+                    c = b.contents()[0];
+
+                var parents = c.parents();
+                // @@
+                expect(parents[0].sameNode(b)).to.be.true;
+                expect(parents[1].sameNode(a)).to.be.true;
+            });
+        });
+
+        describe('finding sibling parents of two elements', function() {
+            it('returns elements themself if they have direct common parent', function() {
+                var doc = getDocumentFromXML('<section><div><div>A</div><div>B</div></div></section>'),
+                    wrappingDiv = doc.root.contents()[0],
+                    divA = wrappingDiv.contents()[0],
+                    divB = wrappingDiv.contents()[1];
+
+                var siblingParents = doc.getSiblingParents({node1: divA, node2: divB});
+
+                expect(siblingParents.node1.sameNode(divA)).to.equal(true, 'divA');
+                expect(siblingParents.node2.sameNode(divB)).to.equal(true, 'divB');
+            });
+
+            it('returns sibling parents - example 1', function() {
+                var doc = getDocumentFromXML('<section>Alice <span>has a cat</span></section>'),
+                    aliceText = doc.root.contents()[0],
+                    span = doc.root.contents()[1],
+                    spanText = span.contents()[0];
+
+                var siblingParents = doc.getSiblingParents({node1: aliceText, node2: spanText});
+
+                expect(siblingParents.node1.sameNode(aliceText)).to.equal(true, 'aliceText');
+                expect(siblingParents.node2.sameNode(span)).to.equal(true, 'span');
+            });
+
+            it('returns node itself for two same nodes', function() {
+                var doc = getDocumentFromXML('<section><div></div></section>'),
+                    div = doc.root.contents()[0];
+
+                var siblingParents = doc.getSiblingParents({node1: div, node2: div});
+                expect(!!siblingParents.node1 && !!siblingParents.node2).to.equal(true, 'nodes defined');
+                expect(siblingParents.node1.sameNode(div)).to.be.equal(true, 'node1');
+                expect(siblingParents.node2.sameNode(div)).to.be.equal(true, 'node2');
+            });
+        });
+    });
+
     describe('Serializing document to WLXML', function() {
         it('keeps document intact when no changes have been made', function() {
             var xmlIn = '<section>Alice<div>has</div>a <span class="uri" meta-uri="http://cat.com">cat</span>!</section>',
@@ -395,6 +1157,554 @@ describe('smartxml', function() {
         });
     });
 
+    describe('Extension API', function() {
+        var doc, extension, elementNode, textNode;
+
+        beforeEach(function() {
+            doc = getDocumentFromXML('<section>Alice<div class="test_class"></div></section>');
+            elementNode = doc.root;
+            textNode = doc.root.contents()[0];
+            extension = {};
+            
+            expect(elementNode.testTransformation).to.be.undefined;
+            expect(textNode.testTransformation).to.be.undefined;
+            expect(doc.testTransformation).to.be.undefined;
+            
+            expect(doc.testMethod).to.be.undefined;
+            expect(elementNode.testMethod).to.be.undefined;
+            expect(textNode.testMethod).to.be.undefined;
+            expect(elementNode.elementTestMethod).to.be.undefined;
+            expect(textNode.textTestMethod).to.be.undefined;
+        });
+
+        it('allows adding method to a document', function() {
+            extension = {document: {methods: {
+                testMethod: function() { return this; }
+            }}};
+
+            doc.registerExtension(extension);
+            expect(doc.testMethod()).to.equal(doc, 'context is set to a document instance');
+        });
+
+        it('allows adding transformation to a document', function() {
+            extension = {document: {transformations: {
+                testTransformation: function() { return this; },
+                testTransformation2: {impl: function() { return this;}}
+            }}};
+
+            doc.registerExtension(extension);
+            expect(doc.testTransformation()).to.equal(doc, 'context is set to a document instance');
+            expect(doc.testTransformation2()).to.equal(doc, 'context is set to a document instance');
+        });
+
+        it('allows adding method to a DocumentNode instance', function() {
+            extension = {
+                documentNode: {
+                    methods: {
+                        testMethod: function() { return this; }
+                    }
+                },
+                textNode: {
+                    methods: {
+                        textTestMethod: function() { return this; }
+                    }
+                },
+                elementNode: {
+                    methods: {
+                        elementTestMethod: function() { return this; }
+                    }
+                }
+            };
+
+            doc.registerExtension(extension);
+
+            /* refresh */
+            elementNode = doc.root;
+            textNode = doc.root.contents()[0];
+
+            expect(elementNode.testMethod().sameNode(elementNode)).to.equal(true, 'context is set to a node instance');
+            expect(textNode.testMethod().sameNode(textNode)).to.equal(true, 'context is set to a node instance');
+
+            expect(elementNode.elementTestMethod().sameNode(elementNode)).to.be.true;
+            expect(elementNode.textTestMethod).to.be.undefined;
+        
+            expect(textNode.textTestMethod().sameNode(textNode)).to.be.true;
+            expect(textNode.elementTestMethod).to.be.undefined;
+        });
+
+        it('allows adding transformation to a DocumentNode', function() {
+            extension = {
+                documentNode: {
+                    transformations: {
+                        testTransformation: function() { return this; },
+                        testTransformation2: {impl: function() { return this;}}
+                    }
+                },
+                textNode: {
+                    transformations: {
+                        textTestTransformation: function() { return this; }
+                    }
+                },
+                elementNode: {
+                    transformations: {
+                        elementTestTransformation: function() { return this; }
+                    }
+                }
+            };
+            
+            doc.registerExtension(extension);
+
+            /* refresh */
+            elementNode = doc.root;
+            textNode = doc.root.contents()[0];
+            
+            expect(elementNode.testTransformation().sameNode(elementNode)).to.equal(true, '1');
+            expect(elementNode.testTransformation2().sameNode(elementNode)).to.equal(true, '2');
+            expect(textNode.testTransformation().sameNode(textNode)).to.equal(true, '3');
+            expect(textNode.testTransformation2().sameNode(textNode)).to.equal(true, '4');
+
+            expect(elementNode.elementTestTransformation().sameNode(elementNode)).to.be.true;
+            expect(elementNode.textTestTransformation).to.be.undefined;
+        
+            expect(textNode.textTestTransformation().sameNode(textNode)).to.be.true;
+            expect(textNode.elementTestTransfomation).to.be.undefined;
+        });
+
+        it('allows text/element node methods and transformations to access node and transormations on document node', function() {
+
+            var doc = getDocumentFromXML('<div>text</div>');
+
+            doc.registerExtension({
+                documentNode: {
+                    methods: {
+                        test: function() {
+                            return 'super';
+                        }
+                    },
+                    transformations: {
+                        testT: function() {
+                            return 'super_trans';
+                        }
+                    }
+                },
+                elementNode: {
+                    methods: {
+                        test: function() {
+                            return 'element_sub_' + this.__super__.test();
+                        }
+                    },
+                    transformations: {
+                        testT: function() {
+                            return 'element_trans_sub_' + this.__super__.testT();
+                        }
+                    }
+                },
+                textNode: {
+                    methods: {
+                        test: function() {
+                            return 'text_sub_' + this.__super__.test();
+                        }
+                    },
+                    transformations: {
+                        testT: function() {
+                            return 'text_trans_sub_' + this.__super__.testT();
+                        }
+                    }
+                }
+            });
+
+            var textNode = doc.root.contents()[0];
+
+            expect(doc.root.test()).to.equal('element_sub_super');
+            expect(textNode.test()).to.equal('text_sub_super');
+            expect(doc.root.testT()).to.equal('element_trans_sub_super_trans');
+            expect(textNode.testT()).to.equal('text_trans_sub_super_trans');
+        });
+    });
+
+    describe('Undo/redo', function() {
+
+        it('smoke tests', function() {
+            var doc = getDocumentFromXML('<div>Alice</div>'),
+                textNode = doc.root.contents()[0];
+
+            expect(doc.undoStack).to.have.length(0);
+            
+            textNode.wrapWith({tagName: 'span', start:1, end:2});
+            expect(doc.undoStack).to.have.length(1, '1');
+            expect(doc.toXML()).to.equal('<div>A<span>l</span>ice</div>');
+
+            doc.undo();
+            expect(doc.undoStack).to.have.length(0, '2');
+            expect(doc.toXML()).to.equal('<div>Alice</div>');
+
+            doc.redo();
+            expect(doc.undoStack).to.have.length(1, '3');
+            expect(doc.toXML()).to.equal('<div>A<span>l</span>ice</div>');
+
+            doc.undo();
+            expect(doc.undoStack).to.have.length(0, '4');
+            expect(doc.toXML()).to.equal('<div>Alice</div>');
+
+            doc.undo();
+            expect(doc.undoStack).to.have.length(0, '5');
+            expect(doc.toXML()).to.equal('<div>Alice</div>');
+        });
+
+        it('smoke tests 2', function() {
+            var doc = getDocumentFromXML('<div>Alice</div>'),
+                textNode = doc.root.contents()[0],
+                path = textNode.getPath();
+
+            textNode.setText('Alice ');
+            textNode.setText('Alice h');
+            textNode.setText('Alice ha');
+            textNode.setText('Alice has');
+
+            expect(textNode.getText()).to.equal('Alice has');
+
+            doc.undo();
+            expect(doc.root.contents()[0].getText()).to.equal('Alice ha', '1');
+
+            doc.undo();
+            expect(doc.root.contents()[0].getText()).to.equal('Alice h', '2');
+
+            doc.redo();
+            expect(doc.root.contents()[0].getText()).to.equal('Alice ha', '3');
+
+            doc.redo();
+            expect(doc.root.contents()[0].getText()).to.equal('Alice has', '4');
+
+            doc.undo();
+            doc.undo();
+            textNode = doc.getNodeByPath(path);
+            textNode.setText('Cat');
+            doc.undo();
+            textNode = doc.getNodeByPath(path);
+            expect(textNode.getText()).to.equal('Alice h');
+        });
+
+        
+        var sampleMethod = function(val) {
+            this._$.attr('x', val);
+            this.triggerChangeEvent();
+        };
+
+        var transformations = {
+            'unaware': sampleMethod,
+            'returning change root': {
+                impl: sampleMethod,
+                getChangeRoot: function() {
+                    return this.context;
+                }
+            },
+            'implementing undo operation': {
+                impl: function(t, val) {
+                    t.oldVal = this.getAttr('x');
+                    sampleMethod.call(this, val);
+                },
+                undo: function(t) {
+                    this.setAttr('x', t.oldVal);
+                }
+            }
+        };
+
+        _.pairs(transformations).forEach(function(pair) {
+            var name = pair[0],
+                transformaton = pair[1];
+
+            describe(name + ' transformation: ', function() {
+                var doc, node, nodePath;
+
+                beforeEach(function() {
+                    doc = getDocumentFromXML('<div><test x="old"></test></div>');
+
+                    doc.registerExtension({elementNode: {transformations: {
+                        test: transformaton
+                    }}});
+
+                    node = doc.root.contents()[0];
+                    nodePath = node.getPath();
+                });
+
+                it('transforms as expected', function() {
+                    node.test('new');
+                    expect(node.getAttr('x')).to.equal('new');
+                });
+
+                it('can be undone', function() {
+                    node.test('new');
+                    doc.undo();
+                    node = doc.getNodeByPath(nodePath);
+                    expect(node.getAttr('x')).to.equal('old');
+                });
+
+                it('can be undone and then redone', function() {
+                    node.test('new');
+                    doc.undo();
+                    doc.redo();
+                    node = doc.getNodeByPath(nodePath);
+                    expect(node.getAttr('x')).to.equal('new');
+                });
+
+                it('handles a sample scenario', function() {
+                    doc.root.contents()[0].test('1');
+                    doc.root.contents()[0].test('2');
+                    doc.root.contents()[0].test('3');
+                    doc.root.contents()[0].test('4');
+                    doc.root.contents()[0].test('5');
+
+                    expect(doc.root.contents()[0].getAttr('x')).to.equal('5', 'after initial transformations');
+                    doc.undo();
+                    expect(doc.root.contents()[0].getAttr('x')).to.equal('4', 'undo 1.1');
+                    doc.undo();
+                    expect(doc.root.contents()[0].getAttr('x')).to.equal('3', 'undo 1.2');
+                    doc.redo();
+                    expect(doc.root.contents()[0].getAttr('x')).to.equal('4', 'redo 1.1');
+                    doc.redo();
+                    expect(doc.root.contents()[0].getAttr('x')).to.equal('5', 'redo 1.2');
+                    doc.undo();
+                    expect(doc.root.contents()[0].getAttr('x')).to.equal('4', 'undo 2.1');
+                    doc.root.contents()[0].test('10');
+                    expect(doc.root.contents()[0].getAttr('x')).to.equal('10', 'additional transformation');
+                    expect(doc.redoStack.length).to.equal(0, 'transformation cleared redo stack');
+                    doc.redo();
+                    expect(doc.root.contents()[0].getAttr('x')).to.equal('10', 'empty redoStack so redo was noop');
+                    doc.undo();
+                    expect(doc.root.contents()[0].getAttr('x')).to.equal('4', 'undoing additional transformation');
+                    doc.redo();
+                    expect(doc.root.contents()[0].getAttr('x')).to.equal('10', 'redoing additional transformation');
+                });
+            });
+        });
+
+        it('smoke tests nested transformations', function() {
+            var doc = getDocumentFromXML('<div></div>');
+
+            doc.registerExtension({elementNode: {transformations: {
+                nested: function(v) {
+                    this._$.attr('innerAttr', v);
+                    this.triggerChangeEvent();
+                },
+                outer: function(v) {
+                    this.nested(v);
+                    this._$.attr('outerAttr', v);
+                    this.triggerChangeEvent();
+                }
+            }}});
+
+            doc.root.outer('test1');
+            doc.root.outer('test2');
+
+            expect(doc.root.getAttr('innerAttr')).to.equal('test2');
+            expect(doc.root.getAttr('outerAttr')).to.equal('test2');
+
+            doc.undo();
+
+            expect(doc.root.getAttr('innerAttr')).to.equal('test1');
+            expect(doc.root.getAttr('outerAttr')).to.equal('test1');
+
+            doc.undo();
+
+            expect(doc.root.getAttr('innerAttr')).to.equal(undefined);
+            expect(doc.root.getAttr('outerAttr')).to.equal(undefined);
+
+            doc.redo();
+
+            expect(doc.root.getAttr('innerAttr')).to.equal('test1');
+            expect(doc.root.getAttr('outerAttr')).to.equal('test1');
+
+            doc.redo();
+
+            expect(doc.root.getAttr('innerAttr')).to.equal('test2');
+            expect(doc.root.getAttr('outerAttr')).to.equal('test2');
+
+        });
+
+        it('ignores transformation if document didn\'t emit change event', function() {
+            var doc = getDocumentFromXML('<div></div>');
+
+            doc.registerExtension({elementNode: {transformations: {
+                test: function() {
+                    // empty
+                }
+            }}});
+
+            doc.root.test();
+            expect(doc.undoStack.length).to.equal(0);
+
+        });
+
+        describe('Transactions', function() {
+            it('allows to undo/redo series of transformations at once', function() {
+                var doc = getDocumentFromXML('<div></div>');
+
+                doc.registerExtension({
+                    elementNode: {transformations: {
+                        test: function(v) {
+                            this.setAttr('test', v);
+                        }
+                    }}
+                });
+
+                doc.startTransaction();
+                doc.root.test('1');
+                doc.root.test('2');
+                doc.root.test('3');
+                doc.endTransaction();
+
+                doc.undo();
+                expect(doc.root.getAttr('test'), '1');
+                doc.redo();
+                expect(doc.root.getAttr('test'), '3');
+                doc.undo();
+                expect(doc.root.getAttr('test'), '1');
+                doc.redo();
+                expect(doc.root.getAttr('test'), '3');
+            });
+
+            it('ignores empty transactions', function() {
+                var doc = getDocumentFromXML('<div></div>');
+                doc.startTransaction();
+                doc.endTransaction();
+                expect(doc.undoStack).to.have.length(0, 'empty transaction doesn\'t get pushed into undo stack');
+            });
+
+            it('doesn\'t break on optimizations', function() {
+                // This is a smoke test checking if optimizations made to transaction undoing
+                // doesnt't break anything.
+                var doc = getDocumentFromXML('<div smart="1" unaware="1"></div>');
+
+                doc.registerExtension({
+                    elementNode: {transformations: {
+                        unaware: function(v) {
+                            this.setAttr('unware', v);
+                            this.triggerChangeEvent();
+                        },
+                        smart: {
+                            impl: function(t, v) {
+                                t.oldVal = this.getAttr('smart');
+                                this.setAttr('smart', v);
+                                this.triggerChangeEvent();
+                            },
+                            undo: function(t) {
+                                this.setAttr('smart', t.oldVal);
+                                this.triggerChangeEvent();
+                            }
+                        }
+                    }}
+                });
+
+                doc.startTransaction();
+                doc.root.smart('2');
+                doc.root.unaware('2');
+                doc.root.smart('3');
+                doc.root.unaware('3');
+                doc.endTransaction();
+
+                doc.undo();
+
+                expect(doc.root.getAttr('smart')).to.equal('1');
+                expect(doc.root.getAttr('unaware')).to.equal('1');
+            });
+
+            it('can have associated metadata', function() {
+                var doc = getDocumentFromXML('<div></div>'),
+                    metadata = Object.create({});
+
+                doc.registerExtension({document: {transformations: {
+                    test: function() {
+                        this.trigger('change');
+                    }
+                }}});
+
+                doc.startTransaction(metadata);
+                doc.test();
+                doc.endTransaction();
+
+                var transaction = doc.undoStack[0];
+                expect(transaction.metadata).to.equal(metadata);
+            });
+
+            it('can be rolled back', function() {
+                var doc = getDocumentFromXML('<root></root>');
+
+                doc.startTransaction();
+                doc.root.append({tagName: 'div'});
+                doc.rollbackTransaction();
+
+                expect(doc.undoStack.length).to.equal(0, 'nothing to undo');
+                expect(doc.root.contents().length).to.equal(0);
+            });
+
+            it('rollbacks and calls error handleor if error gets thrown', function() {
+                var doc = getDocumentFromXML('<root></root>'),
+                    err = new Error(),
+                    spy = sinon.spy();
+                
+                doc.transaction(function() {
+                    doc.root.append({tagName: 'div'});
+                    throw err;
+                }, {error: spy});
+
+                expect(spy.args[0][0]).to.equal(err);
+                expect(doc.root.contents().length).to.equal(0);
+                expect(doc.undoStack.length).to.equal(0);
+            });
+        });
+
+        describe('Regression tests', function() {
+            it('redos correctly after running its own undo followed by unaware transformation undo', function() {
+                var doc = getDocumentFromXML('<section t="0"></section>');
+                
+                doc.registerExtension({elementNode: {transformations: {
+                    unaware: function() {
+                        this.triggerChangeEvent();
+                    },
+                    test: {
+                        impl: function() {
+                            this._$.attr('t', 1);
+                            this.triggerChangeEvent();
+                        },
+                        undo: function() {
+                            this._$.attr('t', 0);
+                        }
+                    }
+                }}});
+                doc.root.unaware();
+                doc.root.test();
+                doc.undo();
+                doc.undo();
+                doc.redo();
+                doc.redo();
+                expect(doc.root.getAttr('t')).to.equal('1');
+            });
+            it('can perform undo of an operation performed after automatic transaction rollback', function() {
+                var doc = getDocumentFromXML('<section></section>'),
+                    extension = {document: {transformations: {
+                        throwingTransformation: function() { throw new Error(); }
+                    }}};
+
+                doc.registerExtension(extension);
+
+                doc.throwingTransformation();
+
+                doc.transaction(function() {
+                    doc.root.setAttr('x', '2');
+                });
+
+                expect(doc.undoStack.length).to.equal(1);
+                expect(doc.root.getAttr('x')).to.equal('2');
+
+                doc.undo();
+
+                expect(doc.undoStack.length).to.equal(0);
+                expect(doc.root.getAttr('x')).to.be.undefined;
+
+            });
+        });
+    });
+
 });
 
 });
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