Add code coverage for ControlCommandSet.cs file (#13130)

Related #10773

## Proposed changes

- Add unit test file: ControlCommandSetTests.cs for public methods and 2
protected methods of the ControlCommandSet.cs.




###### Microsoft Reviewers: [Open in
CodeFlow](https://microsoft.github.io/open-pr/?codeflow=https://github.com/dotnet/winforms/pull/13130)

Author: LeafShi1

Diff for: src/System.Windows.Forms.Design/tests/UnitTests/System/Windows/Forms/Design/ControlCommandSetTests.cs

@@ -0,0 +1,192 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System.ComponentModel;
+using System.ComponentModel.Design;
+using System.Drawing;
+using Moq;
+
+namespace System.Windows.Forms.Design.Tests;
+
+public class ControlCommandSetTests : IDisposable
+{
+    private readonly Mock<ISite> _siteMock;
+    private readonly Mock<IDesignerHost> _designerHostMock;
+    private readonly Mock<IMenuCommandService> _menuServiceMock;
+    private readonly Mock<IEventHandlerService> _eventHandlerServiceMock;
+    private readonly Mock<ISelectionService> _selectionServiceMock;
+    private readonly Mock<IDictionaryService> _dictionaryServiceMock;
+    private readonly ControlCommandSet _controlCommandSet;
+    private readonly Control _baseControl;
+
+    public ControlCommandSetTests()
+    {
+        _siteMock = new();
+        _designerHostMock = new();
+        _menuServiceMock = new();
+        _eventHandlerServiceMock = new();
+        _selectionServiceMock = new();
+        _dictionaryServiceMock = new();
+        _baseControl = new();
+
+        _siteMock.Setup(s => s.GetService(typeof(IDesignerHost))).Returns(_designerHostMock.Object);
+        _siteMock.Setup(s => s.GetService(typeof(IMenuCommandService))).Returns(_menuServiceMock.Object);
+        _siteMock.Setup(s => s.GetService(typeof(IEventHandlerService))).Returns(_eventHandlerServiceMock.Object);
+        _siteMock.Setup(s => s.GetService(typeof(ISelectionService))).Returns(_selectionServiceMock.Object);
+        _siteMock.Setup(s => s.GetService(typeof(IDictionaryService))).Returns(_dictionaryServiceMock.Object);
+        _designerHostMock.Setup(h => h.RootComponent).Returns(_baseControl);
+
+        _controlCommandSet = new(_siteMock.Object);
+    }
+
+    public void Dispose()
+    {
+        _controlCommandSet.Dispose();
+        _baseControl.Dispose();
+    }
+
+    [Fact]
+    public void Constructor_ShouldInitializeCommandSet()
+    {
+        _controlCommandSet.Should().NotBeNull();
+
+        StatusCommandUI statusCommandUI = _controlCommandSet.TestAccessor().Dynamic._statusCommandUI;
+        statusCommandUI.Should().NotBeNull();
+
+        MenuCommand[] commandSet = _controlCommandSet.TestAccessor().Dynamic._commandSet;
+        commandSet.Should().NotBeNull();
+        commandSet.Should().NotBeEmpty();
+
+        TabOrder tabOrder = _controlCommandSet.TestAccessor().Dynamic._tabOrder;
+        tabOrder.Should().BeNull();
+    }
+
+    [Fact]
+    public void Dispose_ShouldRemoveCommandsFromMenuService()
+    {
+        _controlCommandSet.Dispose();
+
+        _menuServiceMock.Verify(m => m.RemoveCommand(It.IsAny<MenuCommand>()), Times.AtLeastOnce);
+    }
+
+    [Fact]
+    public void OnMenuLockControls_ShouldToggleLockControls()
+    {
+        using Control component = new();
+        Mock<IContainer> containerMock = new();
+        _siteMock.Setup(s => s.Container).Returns(containerMock.Object);
+        component.Site = _siteMock.Object;
+
+        _designerHostMock.Setup(h => h.RootComponent).Returns(_baseControl);
+        _designerHostMock.Setup(h => h.Container.Components).Returns(new ComponentCollection([component]));
+
+        CommandID commandID = new(Guid.NewGuid(), 0);
+        MenuCommand menuCommand = new(null, commandID) { Checked = false };
+
+        _controlCommandSet.TestAccessor().Dynamic.OnMenuLockControls(menuCommand, EventArgs.Empty);
+
+        menuCommand.Checked.Should().BeTrue();
+    }
+
+    [Fact]
+    public void GetSnapInformation_WithSnapToGridPropertyInParent_ShouldReturnThatProperty()
+    {
+        using Control childComponent = new();
+        using Control parentComponent = new();
+
+        childComponent.Parent = parentComponent;
+
+        Mock<IContainer> containerMock = new();
+        _siteMock.Setup(s => s.Container).Returns(containerMock.Object);
+        childComponent.Site = _siteMock.Object;
+        parentComponent.Site = _siteMock.Object;
+
+        _designerHostMock.Setup(h => h.RootComponent).Returns(_baseControl);
+
+        Mock<IDesigner> designerMock = new();
+        designerMock.Setup(d => d.Component).Returns(childComponent);
+        _designerHostMock.Setup(h => h.GetDesigner(childComponent)).Returns(designerMock.Object);
+
+        Mock<PropertyDescriptor> snapPropertyDescriptorMock = new("SnapToGrid", Array.Empty<Attribute>());
+        snapPropertyDescriptorMock.Setup(p => p.PropertyType).Returns(typeof(bool));
+        snapPropertyDescriptorMock.Setup(p => p.ComponentType).Returns(typeof(Control));
+        snapPropertyDescriptorMock.Setup(p => p.Name).Returns("SnapToGrid");
+
+        var originalProvider = TypeDescriptor.GetProvider(parentComponent);
+        var mockProvider = new MockTypeDescriptionProvider(originalProvider, snapPropertyDescriptorMock.Object);
+        TypeDescriptor.AddProvider(mockProvider, parentComponent);
+
+        try
+        {
+            _controlCommandSet.TestAccessor().Dynamic.GetSnapInformation(
+                _designerHostMock.Object,
+                childComponent,
+                out Size snapSize,
+                out IComponent snapComponent,
+                out PropertyDescriptor snapProperty);
+
+            snapComponent.Should().Be(parentComponent);
+            snapProperty.Should().NotBeNull();
+            snapProperty.Name.Should().Be("SnapToGrid");
+            snapSize.Should().Be(Size.Empty);
+        }
+        finally
+        {
+            TypeDescriptor.RemoveProvider(mockProvider, parentComponent);
+        }
+    }
+
+    /// <summary>
+    ///  Helper class to provide mock property descriptors.
+    /// </summary>
+    private class MockTypeDescriptionProvider : TypeDescriptionProvider
+    {
+        private readonly TypeDescriptionProvider _baseProvider;
+        private readonly PropertyDescriptor _snapToGridProperty;
+
+        public MockTypeDescriptionProvider(TypeDescriptionProvider baseProvider, PropertyDescriptor snapToGridProperty)
+        {
+            _baseProvider = baseProvider;
+            _snapToGridProperty = snapToGridProperty;
+        }
+
+        public override ICustomTypeDescriptor? GetTypeDescriptor(Type objectType, object? instance)
+        {
+            var baseDescriptor = _baseProvider.GetTypeDescriptor(objectType, instance);
+            return baseDescriptor is not null ? new MockCustomTypeDescriptor(baseDescriptor, _snapToGridProperty) : null;
+        }
+    }
+
+    private class MockCustomTypeDescriptor : CustomTypeDescriptor
+    {
+        private readonly PropertyDescriptor _snapToGridProperty;
+
+        public MockCustomTypeDescriptor(ICustomTypeDescriptor parent, PropertyDescriptor snapToGridProperty)
+            : base(parent)
+        {
+            _snapToGridProperty = snapToGridProperty;
+        }
+
+        public override PropertyDescriptorCollection GetProperties()
+        {
+            PropertyDescriptorCollection baseProperties = base.GetProperties();
+
+            PropertyDescriptor[] allProperties = new PropertyDescriptor[baseProperties.Count + 1];
+            baseProperties.CopyTo(allProperties, 0);
+            allProperties[baseProperties.Count] = _snapToGridProperty;
+
+            return new PropertyDescriptorCollection(allProperties);
+        }
+
+        public override PropertyDescriptorCollection GetProperties(Attribute[]? attributes)
+        {
+            PropertyDescriptorCollection baseProperties = base.GetProperties(attributes);
+
+            PropertyDescriptor[] allProperties = new PropertyDescriptor[baseProperties.Count + 1];
+            baseProperties.CopyTo(allProperties, 0);
+            allProperties[baseProperties.Count] = _snapToGridProperty;
+
+            return new PropertyDescriptorCollection(allProperties);
+        }
+    }
+}