Add Tests

tests/Avalonia.Controls.UnitTests/Primitives/SelectingItemsControlTests_SelectedValue.cs

@@ -0,0 +1,330 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using Avalonia.Controls.Presenters;
+using Avalonia.Controls.Primitives;
+using Avalonia.Controls.Templates;
+using Avalonia.Data;
+using Avalonia.Styling;
+using Avalonia.UnitTests;
+using Xunit;
+
+namespace Avalonia.Controls.UnitTests.Primitives
+{
+    public class SelectingItemsControlTests_SelectedValue
+    {
+        [Fact]
+        public void Setting_SelectedItem_Sets_SelectedValue()
+        {
+            var items = TestClass.GetItems();
+            var sic = new SelectingItemsControl
+            {
+                Items = items,
+                SelectedValueBinding = new Binding("Name"),
+                Template = Template()
+            };
+
+            sic.SelectedItem = items[0];
+
+            Assert.Equal(items[0].Name, sic.SelectedValue);
+        }
+
+        [Fact]
+        public void Setting_SelectedIndex_Sets_SelectedValue()
+        {
+            var items = TestClass.GetItems();
+            var sic = new SelectingItemsControl
+            {
+                Items = items,
+                SelectedValueBinding = new Binding("Name"),
+                Template = Template()
+            };
+
+            sic.SelectedIndex = 0;
+
+            Assert.Equal(items[0].Name, sic.SelectedValue);
+        }
+
+        [Fact]
+        public void Setting_SelectedItems_Sets_SelectedValue()
+        {
+            var items = TestClass.GetItems();
+            var sic = new ListBox
+            {
+                Items = items,
+                SelectedValueBinding = new Binding("Name"),
+                Template = Template()
+            };
+
+            sic.SelectedItems = new List<TestClass>
+            {
+                items[1],
+                items[3],
+                items[4]
+            };
+
+            // When interacting, SelectedItem is the first item in the SelectedItems collection
+            // But when set here, it's the last
+            Assert.Equal(items[4].Name, sic.SelectedValue);
+        }
+
+        [Fact]
+        public void Setting_SelectedValue_Sets_SelectedIndex()
+        {
+            using (UnitTestApplication.Start(TestServices.StyledWindow))
+            {
+                var items = TestClass.GetItems();
+                var sic = new SelectingItemsControl
+                {
+                    Items = items,
+                    SelectedValueBinding = new Binding("Name"),
+                    Template = Template()
+                };
+
+                Prepare(sic);
+
+                sic.SelectedValue = items[1].Name;
+
+                Assert.Equal(1, sic.SelectedIndex);
+            }                
+        }
+
+        [Fact]
+        public void Setting_SelectedValue_Sets_SelectedItem()
+        {
+            using (UnitTestApplication.Start(TestServices.StyledWindow))
+            {
+                var items = TestClass.GetItems();
+                var sic = new SelectingItemsControl
+                {
+                    Items = items,
+                    SelectedValueBinding = new Binding("Name"),
+                    Template = Template()
+                };
+
+                Prepare(sic);
+
+                sic.SelectedValue = "Item2";
+
+                Assert.Equal(items[1], sic.SelectedItem);
+            }                
+        }
+
+        [Fact]
+        public void Changing_SelectedValueBinding_Updates_SelectedValue()
+        {
+            using (UnitTestApplication.Start(TestServices.StyledWindow))
+            {
+                var items = TestClass.GetItems();
+                var sic = new SelectingItemsControl
+                {
+                    Items = items,
+                    SelectedValueBinding = new Binding("Name"),
+                    Template = Template()
+                };
+
+                sic.SelectedValue = "Item2";
+
+                sic.SelectedValueBinding = new Binding("AltProperty");
+
+                // Ensure SelectedItem didn't change
+                Assert.Equal(items[1], sic.SelectedItem);
+
+
+                Assert.Equal("Alt2", sic.SelectedValue);
+            }                         
+        }
+
+        [Fact]
+        public void SelectedValue_With_Null_SelectedValueBinding_Is_Item()
+        {
+            var items = TestClass.GetItems();
+            var sic = new SelectingItemsControl
+            {
+                Items = items,
+                Template = Template()
+            };
+
+            sic.SelectedIndex = 0;
+
+            Assert.Equal(items[0], sic.SelectedValue);
+        }
+
+        [Fact]
+        public void Setting_SelectedValue_Before_Initialize_Should_Retain_Selection()
+        {
+            var items = TestClass.GetItems();
+            var sic = new SelectingItemsControl
+            {
+                Items = items,
+                Template = Template(),
+                SelectedValueBinding = new Binding("Name"),
+                SelectedValue = "Item2"
+            };
+
+            sic.BeginInit();
+            sic.EndInit();
+
+            Assert.Equal(items[1].Name, sic.SelectedValue);
+        }
+
+        [Fact]
+        public void Setting_SelectedValue_During_Initialize_Should_Take_Priority_Over_Previous_Value()
+        {
+            var items = TestClass.GetItems();
+            var sic = new SelectingItemsControl
+            {
+                Items = items,
+                Template = Template(),
+                SelectedValueBinding = new Binding("Name"),
+                SelectedValue = "Item2"
+            };
+
+            sic.BeginInit();
+            sic.SelectedValue = "Item1";
+            sic.EndInit();
+
+            Assert.Equal(items[0].Name, sic.SelectedValue);
+        }
+
+        [Fact]
+        public void Changing_Items_Should_Clear_SelectedValue()
+        {
+            using (UnitTestApplication.Start(TestServices.StyledWindow))
+            {
+                var items = TestClass.GetItems();
+                var sic = new SelectingItemsControl
+                {
+                    Items = items,
+                    Template = Template(),
+                    SelectedValueBinding = new Binding("Name"),
+                    SelectedValue = "Item2"
+                };
+
+                Prepare(sic);
+
+                sic.Items = new List<TestClass>
+                {
+                    new TestClass("NewItem", string.Empty)
+                };
+
+                Assert.Equal(null, sic.SelectedValue);
+            }
+        }
+
+        [Fact]
+        public void Setting_SelectedValue_Should_Raise_SelectionChanged_Event()
+        {
+            // Unlike SelectedIndex/SelectedItem tests, we need the ItemsControl to
+            // initialize so that SelectedValue can actually be looked up
+            using (UnitTestApplication.Start(TestServices.StyledWindow))
+            {
+                var items = TestClass.GetItems();
+                var sic = new SelectingItemsControl
+                {
+                    Items = items,
+                    Template = Template(),
+                    SelectedValueBinding = new Binding("Name"),
+                };
+
+                Prepare(sic);
+
+                var called = false;
+                sic.SelectionChanged += (s, e) =>
+                {
+                    Assert.Same(items[1], e.AddedItems.Cast<object>().Single());
+                    Assert.Empty(e.RemovedItems);
+                    called = true;
+                };
+
+                sic.SelectedValue = "Item2";
+                Assert.True(called);
+            }
+        }
+
+        [Fact]
+        public void Clearing_SelectedValue_Should_Raise_SelectionChanged_Event()
+        {
+            var items = TestClass.GetItems();
+            var sic = new SelectingItemsControl
+            {
+                Items = items,
+                Template = Template(),
+                SelectedValueBinding = new Binding("Name"),
+                SelectedValue = "Item2"
+            };
+
+            var called = false;
+            sic.SelectionChanged += (s, e) =>
+            {
+                Assert.Same(items[1], e.RemovedItems.Cast<object>().Single());
+                Assert.Empty(e.AddedItems);
+                called = true;
+            };
+
+            sic.SelectedValue = null;
+            Assert.True(called);
+        }
+
+        private static FuncControlTemplate Template()
+        {
+            return new FuncControlTemplate<SelectingItemsControl>((control, scope) =>
+                new ItemsPresenter
+                {
+                    Name = "itemsPresenter",
+                    [~ItemsPresenter.ItemsPanelProperty] = control[~ItemsControl.ItemsPanelProperty],
+                }.RegisterInNameScope(scope));
+        }
+
+        private static void Prepare(SelectingItemsControl target)
+        {
+            var root = new TestRoot
+            {
+                Child = target,
+                Width = 100,
+                Height = 100,
+                Styles =
+                {
+                    new Style(x => x.Is<SelectingItemsControl>())
+                    {
+                        Setters =
+                        {
+                            new Setter(ListBox.TemplateProperty, Template()),
+                        },
+                    },
+                },
+            };
+
+            root.LayoutManager.ExecuteInitialLayoutPass();
+        }
+    }
+
+    internal class TestClass
+    {
+        public TestClass(string name, string alt)
+        {
+            Name = name;
+            AltProperty = alt;
+        }
+
+        public string Name { get; set; }
+
+        public string AltProperty { get; set; }
+
+        public static List<TestClass> GetItems()
+        {
+            return new List<TestClass>
+            {
+                new TestClass("Item1", "Alt1"),
+                new TestClass("Item2", "Alt2"),
+                new TestClass("Item3", "Alt3"),
+                new TestClass("Item4", "Alt4"),
+                new TestClass("Item5", "Alt5"),
+            };
+        }
+    }
+}
+
+