Merge pull request #230 from chuuddo/fix-missing-parent

Fix adding parent after child in TransformToTree
reactivemarbles · Jun 10, 2019 · 16d5a9c · 16d5a9c
2 parents b6d60da + de94676
commit 16d5a9c
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Showing 2 changed files with 41 additions and 21 deletions.
diff --git a/DynamicData.Tests/Cache/TransformTreeFixture.cs b/DynamicData.Tests/Cache/TransformTreeFixture.cs
@@ -126,19 +126,33 @@ public void AddMissingChild()
         [Fact]
         public void AddMissingParent()
         {
-            var minion = new EmployeeDto(1) { BossId = 2, Name = "DogsBody" };
-            var boss = new EmployeeDto(2) { BossId = 0, Name = "Boss" };
+            var emp10 = new EmployeeDto(10) { BossId = 11, Name = "Employee10" };
+            var emp11 = new EmployeeDto(11) { BossId = 0, Name = "Employee11" };
+            var emp12 = new EmployeeDto(12) { BossId = 13, Name = "Employee12" };
+            var emp13 = new EmployeeDto(13) { BossId = 11, Name = "Employee13" };
 
-            _sourceCache.AddOrUpdate(boss);
-            _sourceCache.AddOrUpdate(minion);
+            _sourceCache.AddOrUpdate(emp10);
+            _sourceCache.AddOrUpdate(emp11);
+            _sourceCache.AddOrUpdate(emp12);
+            _sourceCache.AddOrUpdate(emp13);
 
             _result.Count.Should().Be(1);
 
-            var firstNode = _result.Items.First();
-            firstNode.Item.Should().Be(boss);
+            var emp11Node = _result.Lookup(11);
+            emp11Node.HasValue.Should().BeTrue();
+            emp11Node.Value.Children.Count.Should().Be(2);
 
-            var childNode = firstNode.Children.Items.First();
-            childNode.Item.Should().Be(minion);
+            var emp10Node = emp11Node.Value.Children.Lookup(10);
+            emp10Node.HasValue.Should().BeTrue();
+            emp10Node.Value.Children.Count.Should().Be(0);
+
+            var emp13Node = emp11Node.Value.Children.Lookup(13);
+            emp13Node.HasValue.Should().BeTrue();
+            emp13Node.Value.Children.Count.Should().Be(1);
+
+            var emp12Node = emp13Node.Value.Children.Lookup(12);
+            emp12Node.HasValue.Should().BeTrue();
+            emp12Node.Value.Children.Count.Should().Be(0);
         }
 
         [Fact]
@@ -165,19 +179,6 @@ public void ChangeParent()
             emp3.Children.Lookup(4).HasValue.Should().BeFalse();
         }
 
-        [Fact]
-        public void AddParent()
-        {
-            _sourceCache.AddOrUpdate(new EmployeeDto(1) { BossId = 2, Name = "E1" });
-            _sourceCache.AddOrUpdate(new EmployeeDto(2) { BossId = 1, Name = "E2" });
-
-            //we expect the children of node 4  to be pushed up become new roots
-            _result.Count.Should().Be(1);
-
-            var firstNode = _result.Items.First();
-            firstNode.Item.Id.Should().Be(1);
-        }
-
         [Fact]
         public void UseCustomFilter()
         {

diff --git a/DynamicData/Cache/Internal/TreeBuilder.cs b/DynamicData/Cache/Internal/TreeBuilder.cs
@@ -41,6 +41,22 @@ public TreeBuilder([NotNull] IObservable<IChangeSet<TObject, TKey>> source, [Not
                                       .Transform((t, v) => new Node<TObject, TKey>(t, v))
                                       .AsObservableCache();
 
+                var groupedByPivot = allNodes.Connect()
+                                             .Synchronize(locker)
+                                             .Group(x => _pivotOn(x.Item))
+                                             .AsObservableCache();
+                
+                void UpdateChildren(Node<TObject, TKey> parentNode)
+                {
+                    var lookup = groupedByPivot.Lookup(parentNode.Key);
+                    if (lookup.HasValue)
+                    {
+                        var children = lookup.Value.Cache.Items;
+                        parentNode.Update(u => u.AddOrUpdate(children));
+                        children.ForEach(x => x.Parent = parentNode);
+                    }
+                }
+
                 //as nodes change, maintain parent and children
                 var parentSetter = allNodes.Connect()
                                            .Do(changes =>
@@ -65,6 +81,7 @@ public TreeBuilder([NotNull] IObservable<IChangeSet<TObject, TKey>> source, [Not
                                                            switch (change.Reason)
                                                            {
                                                                case ChangeReason.Add:
+                                                                   UpdateChildren(change.Current);
                                                                    break;
                                                                case ChangeReason.Update:
                                                                    {
@@ -129,6 +146,7 @@ public TreeBuilder([NotNull] IObservable<IChangeSet<TObject, TKey>> source, [Not
                                                                            // update the parent node
                                                                            node.Parent = p;
                                                                            updater.AddOrUpdate(node);
+                                                                           UpdateChildren(node);
 
                                                                            break;
                                                                        }
@@ -198,6 +216,7 @@ public TreeBuilder([NotNull] IObservable<IChangeSet<TObject, TKey>> source, [Not
                     parentSetter.Dispose();
                     allData.Dispose();
                     allNodes.Dispose();
+                    groupedByPivot.Dispose();
                     refilterObservable.OnCompleted();
                 });
             });