Synnefo » Pithos MS Client

// -----------------------------------------------------------------------

// <copyright file="TestDifferencer.cs" company="Microsoft">

// TODO: Update copyright text.

// </copyright>

// -----------------------------------------------------------------------

using System.Collections;

using NUnit.Framework;

using Pithos.Interfaces;

using Pithos.Network;

namespace Pithos.Core.Test

{

    using System;

    using System.Collections.Generic;

    using System.Linq;

    using System.Text;

    using Pithos.Core.Agents;

    [TestFixture]

    public class SnapshotDifferencerTest

    {

        private ObjectInfo[] _previous;

        private ObjectInfo[] _current;

        readonly IEqualityComparer<ObjectInfo> _comparer = new ObjectInfoComparer();

        private readonly Uri _testUri = new Uri("http://test");

        [SetUp]

        public void Setup()

        {

            _previous = new []{

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="1"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="2"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name3",Bytes=123,Hash="aa3",Version=1,UUID="3"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name4",Bytes=123,Hash="aa4",Version=1,UUID="4"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Folder1/Name1",Bytes=123,Hash="aa4",Version=1,UUID="5"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont1",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="6"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont1",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="7"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="8"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="9"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name3",Bytes=123,Hash="aa3",Version=1,UUID="10"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name4",Bytes=123,Hash="aa4",Version=1,UUID="11"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont2",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="12"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont2",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="13"},

                            };

            _current = new []{

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="2"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name3",Bytes=123,Hash="aa3",Version=1,UUID="3"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name4",Bytes=1234,Hash="aa45",Version=1,UUID="4"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name5",Bytes=123,Hash="aa5",Version=1,UUID="14"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Folder1/Name1",Bytes=123,Hash="aa4",Version=1,UUID="5"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont1",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="6"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont1",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="7"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="9"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name3",Bytes=123,Hash="aa3",Version=1,UUID="10"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name4",Bytes=1234,Hash="aa45",Version=1,UUID="11"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name5",Bytes=123,Hash="aa5",Version=1,UUID="15"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont2",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="12"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont2",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="13"},

                           };

        }

        [Test]

        public void when_adding_a_snapshot_for_the_first_time()

        {

            var d1 = new SnapshotDifferencer();            

            var differencer=d1.Post(_previous);

            Assert.That(differencer.Deleted,Is.Empty);

            Assert.That(differencer.Created,Is.EquivalentTo(_previous));

            Assert.That(differencer.Changed,Is.Empty);

            Assert.That(differencer.Moved, Is.Empty, "should have no moves");

            Assert.That(differencer.Unchanged,Is.Empty);

        }

        [Test]

        public void when_adding_a_second_snapshot_with_a_deletion()

        {

            var d1 = new SnapshotDifferencer();            

            var differencer=d1.Post(_previous).Post(_current);

            var deleted=new[]

                            {

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="1"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="8"},

                            };

            Assert.That(differencer.Deleted.ToList(),Is.EquivalentTo(deleted)

                .Using((IEqualityComparer) new ObjectInfoComparer()));

        }

        [Test]

        public void when_adding_a_second_snapshot_with_an_addition()

        {

            var d1 = new SnapshotDifferencer();            

            var differencer=d1.Post(_previous).Post(_current);

            var created = new[]

                              {

                                  new ObjectInfo { Account = "acc1", Container = "Cont1", Name = "Name5", Bytes = 123, Hash = "aa5", Version = 1,UUID="14" },

                                  new ObjectInfo { Account = "acc1", Container = "Cont2", Name = "Name5", Bytes = 123, Hash = "aa5", Version = 1,UUID="15" },

                              };

            Assert.That(differencer.Created.ToList(), Is.EquivalentTo(created)

                .Using((IEqualityComparer)new ObjectInfoComparer()));

        }

        [Test]

        public void when_adding_a_second_snapshot_with_a_change()

        {

            var d1 = new SnapshotDifferencer();            

            var differencer=d1.Post(_previous).Post(_current);

            var changed = new[] { 

                new ObjectInfo { Account = "acc1", Container = "Cont1", Name = "Name4", Bytes = 1234, Hash = "aa45", PreviousHash="aa4", Version = 1,UUID="4" },

                new ObjectInfo { Account = "acc1", Container = "Cont2", Name = "Name4", Bytes = 1234, Hash = "aa45", PreviousHash="aa4", Version = 1,UUID="11" },

            };

            Comparison<ObjectInfo> comparer = (x, y) =>

                                                  {

                                                      if (x.Account == y.Account

                                                          && x.Container == y.Container

                                                          && x.Name == y.Name

                                                          && x.Hash == y.Hash

                                                          && x.PreviousHash == y.PreviousHash)

                                                          return 0;

                                                      return 1;

                                                  };

            Assert.That(differencer.Changed.ToList(), Is.EquivalentTo(changed).Using(comparer));

        }

        [Test]

        public void when_adding_a_second_snapshot_with_a_rename()

        {

            var d1 = new SnapshotDifferencer();

            var current = new[]{

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="1"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="2"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name3a",Bytes=123,Hash="aa3",Version=1,UUID="3"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name4",Bytes=123,Hash="aa4",Version=1,UUID="4"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Folder1/Name1",Bytes=123,Hash="aa4",Version=1,UUID="5"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont1",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="6"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont1",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="7"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="8"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="9"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name3",Bytes=123,Hash="aa3",Version=1,UUID="10"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name4",Bytes=123,Hash="aa4",Version=1,UUID="11"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont2",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="12"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont2",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="13"},

                            };

            var differencer=d1.Post(_previous).Post(current);

            var moved = new[] { 

                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name3a",Bytes=123,Hash="aa3",PreviousHash="aa3",Version=1,UUID="3"}

            };

            Comparison<ObjectInfo> comparer = (x, y) =>

                                                  {

                                                      if (x.Account == y.Account

                                                          && x.Container == y.Container

                                                          && x.Name == y.Name

                                                          && x.Hash == y.Hash

                                                          && x.PreviousHash == y.PreviousHash)

                                                          return 0;

                                                      return 1;

                                                  };

            Assert.That(differencer.Moved.ToList(), Is.EquivalentTo(moved).Using(comparer));

            Assert.That(differencer.Deleted, Is.Empty);

            Assert.That(differencer.Created, Is.Empty);

            Assert.That(differencer.Changed, Is.Empty);

            //Assert.That(differencer.Unchanged, Is.Empty);

            Assert.That(differencer.Moved.ToList(), Is.EquivalentTo(moved).Using(comparer));

        }

        [Test]

        public void when_adding_a_second_snapshot_with_a_changed_rename()

        {

            var d1 = new SnapshotDifferencer();

            var current = new[]{

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="1"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="2"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name3a",Bytes=123,Hash="aa35",Version=1,UUID="3"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name4",Bytes=123,Hash="aa4",Version=1,UUID="4"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Folder1/Name1",Bytes=123,Hash="aa4",Version=1,UUID="5"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont1",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="6"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont1",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="7"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="8"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="9"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name3",Bytes=123,Hash="aa3",Version=1,UUID="10"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name4",Bytes=123,Hash="aa4",Version=1,UUID="11"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont2",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="12"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont2",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="13"},

                            };

            var unchanged = new[]{

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="1",PreviousHash="aa1"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="2",PreviousHash="aa2"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name4",Bytes=123,Hash="aa4",Version=1,UUID="4",PreviousHash="aa4"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Folder1/Name1",Bytes=123,Hash="aa4",Version=1,UUID="5",PreviousHash="aa4"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont1",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="6",PreviousHash="aa1"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont1",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="7",PreviousHash="aa2"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="8",PreviousHash="aa1"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="9",PreviousHash="aa2"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name3",Bytes=123,Hash="aa3",Version=1,UUID="10",PreviousHash="aa3"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name4",Bytes=123,Hash="aa4",Version=1,UUID="11",PreviousHash="aa4"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont2",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="12",PreviousHash="aa1"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont2",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="13",PreviousHash="aa2"},

                            };

            var differencer = d1.Post(_previous).Post(current);

            var moved = new[] { 

                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name3a",Bytes=123,Hash="aa35",PreviousHash="aa3",Version=1,UUID="3"}

            };

            Comparison<ObjectInfo> comparer = (x, y) =>

            {

                if (x.Account == y.Account

                    && x.Container == y.Container

                    && x.Name == y.Name

                    && x.Hash == y.Hash

                    && x.PreviousHash == y.PreviousHash)

                    return 0;

                return 1;

            };

            Assert.That(differencer.Moved.ToList(), Is.EquivalentTo(moved).Using(comparer));

            Assert.That(differencer.Deleted, Is.Empty);

            Assert.That(differencer.Created, Is.Empty);

            Assert.That(differencer.Changed, Is.Empty);

            Assert.That(differencer.Unchanged, Is.EquivalentTo(unchanged).Using(comparer));

        }

        [Test]

        public void when_adding_a_second_snapshot_with_a_move()

        {

            var d1 = new SnapshotDifferencer();

            var current = new[]{

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="1"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="2"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Folder1/Name3",Bytes=123,Hash="aa3",Version=1,UUID="3"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name4",Bytes=123,Hash="aa4",Version=1,UUID="4"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Folder1/Name1",Bytes=123,Hash="aa4",Version=1,UUID="5"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont1",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="6"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont1",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="7"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="8"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="9"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name3",Bytes=123,Hash="aa3",Version=1,UUID="10"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name4",Bytes=123,Hash="aa4",Version=1,UUID="11"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont2",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="12"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont2",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="13"},

                            };

            var differencer=d1.Post(_previous).Post(current);

            var moved = new[] { 

                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Folder1/Name3",Bytes=123,Hash="aa3",PreviousHash="aa3",Version=1},

            };

            Comparison<ObjectInfo> comparer = (x, y) =>

                                                  {

                                                      if (x.Account == y.Account

                                                          && x.Container == y.Container

                                                          && x.Name == y.Name

                                                          && x.Hash == y.Hash

                                                          && x.PreviousHash == y.PreviousHash)

                                                          return 0;

                                                      return 1;

                                                  };

            Assert.That(differencer.Deleted, Is.Empty);

            Assert.That(differencer.Created, Is.Empty);

            Assert.That(differencer.Changed, Is.Empty);

            //Assert.That(differencer.Unchanged, Is.Empty);

            Assert.That(differencer.Moved.ToList(), Is.EquivalentTo(moved).Using(comparer));

        }

        [Test]

        public void when_adding_a_second_snapshot_with_unchanged()

        {

            var d1 = new SnapshotDifferencer();            

            var differencer=d1.Post(_previous).Post(_current);

            var unchanged = new[]

                                {

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="2"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name3",Bytes=123,Hash="aa3",Version=1,UUID="3"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont1",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="6"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont1",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="7"},  

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Folder1/Name1",Bytes=123,Hash="aa4",Version=1,UUID="5"},  

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="9"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name3",Bytes=123,Hash="aa3",Version=1,UUID="10"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont2",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="12"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont2",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="13"},                                    

                                };            

            Assert.That(differencer.Unchanged.ToList(), Is.EquivalentTo(unchanged)

                .Using((IEqualityComparer)new ObjectInfoComparer()));

        }

        [Test]

        public void when_adding_a_null_first_snapshot()

        {

            var d1 = new SnapshotDifferencer();            

            var differencer=d1.Post(null);

            Assert.That(differencer.Deleted, Is.Empty);

            Assert.That(differencer.Created, Is.Empty);

            Assert.That(differencer.Changed, Is.Empty);

            Assert.That(differencer.Moved, Is.Empty, "should have no moves");

            Assert.That(differencer.Unchanged, Is.Empty);

        }

        [Test]

        public void when_adding_a_null_second_snapshot()

        {

            var d1 = new SnapshotDifferencer();            

            var differencer=d1.Post(_previous).Post(null);

            Assert.That(differencer.Deleted, Is.EquivalentTo(_previous));

            Assert.That(differencer.Created, Is.Empty);

            Assert.That(differencer.Changed, Is.Empty);

            Assert.That(differencer.Moved, Is.Empty, "should have no moves");

            Assert.That(differencer.Unchanged, Is.Empty);

        }

        [Test]

        public void when_adding_no_modifications()

        {

            var d1 = new SnapshotDifferencer();

            //NOTE: Must post nomods for all accounts and contaienrs, otherwise the missing

            //containers will appear deleted

            var noModItem = new[]{

                                    new NoModificationInfo("acc1", "Cont1"),

                                    new NoModificationInfo("acc1", "Cont2"),

                                    new NoModificationInfo("acc2", "Cont1"),

                                    new NoModificationInfo("acc2", "Cont2"),

                                };

            var differencer = d1.Post(_previous)

                .Post(noModItem);

            Assert.That(differencer.Deleted, Is.Empty,"should have no deletions");

            Assert.That(differencer.Created, Is.Empty,"should have no insertions");

            Assert.That(differencer.Changed, Is.Empty,"should have no changes");

            Assert.That(differencer.Moved, Is.Empty, "should have no moves");

            Assert.That(differencer.Unchanged, Is.EquivalentTo(_previous),"should be equivalent to previous");

        }

        [Test]

        public void when_adding_no_mod_for_a_folder()

        {

            var d1 = new SnapshotDifferencer();

            //NOTE: Must post nomods for all accounts and contaienrs, otherwise the missing

            //containers will appear deleted

            var noModItems = new[]{

                                    new NoModificationInfo("acc1", "Cont1","Folder1"),

                                    new NoModificationInfo("acc1", "Cont2"),

                                    new NoModificationInfo("acc2", "Cont1"),

                                    new NoModificationInfo("acc2", "Cont2"),

                                };

            var deleted = new[]

                            {

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="1"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="2"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name3",Bytes=123,Hash="aa3",Version=1,UUID="3"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Name4",Bytes=123,Hash="aa4",Version=1,UUID="4"},

                            };

            var unchanged = new[]{

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont1",Name="Folder1/Name1",Bytes=123,Hash="aa4",Version=1,UUID="5",PreviousHash="aa4"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont1",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="6",PreviousHash="aa1"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont1",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="7",PreviousHash="aa2"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="8",PreviousHash="aa1"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="9",PreviousHash="aa2"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name3",Bytes=123,Hash="aa3",Version=1,UUID="10",PreviousHash="aa3"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc1",Container="Cont2",Name="Name4",Bytes=123,Hash="aa4",Version=1,UUID="11",PreviousHash="aa4"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont2",Name="Name1",Bytes=123,Hash="aa1",Version=1,UUID="12",PreviousHash="aa1"},

                                new ObjectInfo{StorageUri=_testUri,Account="acc2",Container="Cont2",Name="Name2",Bytes=123,Hash="aa2",Version=1,UUID="13",PreviousHash="aa2"},

                            };

            var differencer = d1.Post(_previous)

                .Post(noModItems);

            Assert.That(differencer.Deleted.ToList(), Is.EquivalentTo(deleted).Using(_comparer), "should have deletions only from acc1/cont1");

            Assert.That(differencer.Created, Is.Empty,"should have no insertions");

            Assert.That(differencer.Changed, Is.Empty,"should have no changes");

            Assert.That(differencer.Moved, Is.Empty, "should have no moves");

            var actualUnchanged = differencer.Unchanged.OrderBy(i => i.Uri.ToString()).ToArray();

            var expectedUnchanged = unchanged.OrderBy(i => i.Uri.ToString()).ToArray();

            Assert.That(actualUnchanged, Is.EquivalentTo(expectedUnchanged).Using(_comparer),"should be equivalent to previous except the direct leafs of acc1/cont1");

        }

    }

}