From 33032f7b76f171427aa580ca9049c9710ba09114 Mon Sep 17 00:00:00 2001
From: Jtfk <Jtfk@users.noreply.github.com>
Date: Sun, 4 Jun 2023 16:30:48 +0800
Subject: [PATCH] fix(module: tree): fix IList `DataSource` cannot be modify in
 place (#3275)

* fix(module: tree): skip `ToList()` when type is `IList`

This allow DataSource to be modify by TreeNode draggable methods.

* test(module: tree): add test for TreeNode modify DataSource
---
 components/tree/TreeNode.razor.cs          |  11 ++-
 tests/AntDesign.Tests/Tree/TreeTests.razor | 104 +++++++++++++++++++++
 2 files changed, 113 insertions(+), 2 deletions(-)
 create mode 100644 tests/AntDesign.Tests/Tree/TreeTests.razor

diff --git a/components/tree/TreeNode.razor.cs b/components/tree/TreeNode.razor.cs
index 9f5ed796..44041f72 100644
--- a/components/tree/TreeNode.razor.cs
+++ b/components/tree/TreeNode.razor.cs
@@ -713,7 +713,14 @@ namespace AntDesign
             get
             {
                 if (TreeComponent.ChildrenExpression != null)
-                    return TreeComponent.ChildrenExpression(this)?.ToList() ?? new List<TItem>();
+                {
+                    var childItems = TreeComponent.ChildrenExpression(this);
+                    if (childItems is IList<TItem> list)
+                    {
+                        return list;
+                    }
+                    return childItems?.ToList() ?? new List<TItem>();
+                }
                 else
                     return new List<TItem>();
             }
@@ -728,7 +735,7 @@ namespace AntDesign
             if (this.ParentNode != null)
                 return this.ParentNode.ChildDataItems;
             else
-                return this.TreeComponent.DataSource.ToList();
+                return this.TreeComponent.DataSource as IList<TItem> ?? this.TreeComponent.DataSource.ToList();
         }
 
         #endregion data binding
diff --git a/tests/AntDesign.Tests/Tree/TreeTests.razor b/tests/AntDesign.Tests/Tree/TreeTests.razor
new file mode 100644
index 00000000..cca1116f
--- /dev/null
+++ b/tests/AntDesign.Tests/Tree/TreeTests.razor
@@ -0,0 +1,104 @@
+@inherits AntDesignTestBase
+
+@code {
+
+    record Item(string Name)
+    {
+        public List<Item> Children { get; set; } = new();
+    };
+
+    [Fact]
+    public async Task Parent_MoveDown_item_mutate_datasource()
+    {
+        var data = new List<Item>
+        {
+            new Item("Item 1"),
+            new Item("Item 2"),
+        };
+
+        var cut = Render<Tree<Item>>(@<Tree TItem="Item" DataSource="data"/>);
+        var firstItem = cut.FindComponent<TreeNode<Item>>();
+
+        var firstItemIndex = data.IndexOf(firstItem.Instance.DataItem) + 1;
+        firstItem.Instance.MoveDown();
+
+        var resultList = firstItem.Instance.GetParentChildDataItems();
+        resultList.Should().HaveElementAt(firstItemIndex, firstItem.Instance.DataItem, "DataSource should be mutated");
+    }
+
+    [Fact]
+    public async Task Parent_Remove_item_mutate_datasource()
+    {
+        var data = new List<Item>
+        {
+            new Item("Item 1"),
+            new Item("Item 2"),
+        };
+
+        var cut = Render<Tree<Item>>(@<Tree TItem="Item" DataSource="data"/>);
+        var firstItem = cut.FindComponent<TreeNode<Item>>();
+        firstItem.Instance.Remove();
+
+        data.Should().NotContain(firstItem.Instance.DataItem, "Item should be removed in DataSource");
+    }
+
+    [Fact]
+    public async Task Children_MoveDown_item_mutate_datasource()
+    {
+        var data = new List<Item>
+        {
+            new Item("Item 1")
+            {
+                Children = new List<Item>
+                {
+                    new Item("Child 1-1"),
+                    new Item("Child 1-2"),
+                }
+            },
+        };
+
+        var cut = Render<Tree<Item>>(
+            @<Tree TItem="Item"
+                   DataSource="data"
+                   ChildrenExpression="node => node.DataItem.Children">
+            </Tree>);
+
+        var treeNodes = cut.FindComponents<TreeNode<Item>>();
+        var childComponent = treeNodes.First(component => component.Instance.DataItem.Name.Equals("Child 1-1"));
+
+        var childItemIndex = data[0].Children.IndexOf(childComponent.Instance.DataItem) + 1;
+        childComponent.Instance.MoveDown();
+
+        var resultList = childComponent.Instance.GetParentChildDataItems();
+        resultList.Should().HaveElementAt(childItemIndex, childComponent.Instance.DataItem, "DataSource should be mutated");
+    }
+
+    [Fact]
+    public async Task Children_Remove_item_mutate_datasource()
+    {
+        var data = new List<Item>
+        {
+            new Item("Item 1")
+            {
+                Children = new List<Item>
+                {
+                    new Item("Child 1-1"),
+                    new Item("Child 1-2"),
+                }
+            },
+        };
+
+        var cut = Render<Tree<Item>>(
+            @<Tree TItem="Item"
+                   DataSource="data"
+                   ChildrenExpression="node => node.DataItem.Children">
+            </Tree>);
+
+        var treeNodes = cut.FindComponents<TreeNode<Item>>();
+        var childComponent = treeNodes.First(component => component.Instance.DataItem.Name.Equals("Child 1-2"));
+        childComponent.Instance.Remove();
+
+        data[0].Children.Should().NotContain(childComponent.Instance.DataItem, "Item should be removed in DataSource");
+    }
+
+}