Add unit tests for DesignerFrame

src/System.Windows.Forms.Design/tests/UnitTests/System/Windows/Forms/Design/DesignerFrameTests.cs

@@ -0,0 +1,112 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+#nullable enable
+
+using System.ComponentModel;
+using System.Drawing;
+using Moq;
+
+namespace System.Windows.Forms.Design.Tests;
+
+public class DesignerFrameTests
+{
+    [Fact]
+    public void DesignerFrame_Constructor_SetsProperties()
+    {
+        Mock<ISite> mockSite = new();
+        Mock<IUIService> mockUIService = new();
+        mockUIService.Setup(ui => ui.Styles["ArtboardBackground"]).Returns(Color.Red);
+        mockSite.Setup(site => site.GetService(typeof(IUIService))).Returns(mockUIService.Object);
+
+        DesignerFrame designerFrame = new(mockSite.Object);
+
+        designerFrame.Text.Should().Be("DesignerFrame");
+        designerFrame.BackColor.Should().Be(Color.Red);
+
+        designerFrame.Controls.Cast<Control>().Should().HaveCount(1);
+    }
+
+    [Fact]
+    public void DesignerFrame_Initialize_SetsDesignerProperties()
+    {
+        Mock<ISite> mockSite = new();
+        Control control = new();
+        DesignerFrame designerFrame = new(mockSite.Object);
+
+        designerFrame.Initialize(control);
+
+        List<Control> controls = designerFrame.Controls.Cast<Control>().ToList();
+        Control? designerRegion = controls.FirstOrDefault(c => c is ScrollableControl);
+
+        designerRegion.Should().NotBeNull();
+
+        Control? designer = designerRegion?.Controls.Cast<Control>().FirstOrDefault();
+        designer.Should().Be(control);
+
+        control.Visible.Should().BeTrue();
+        control.Enabled.Should().BeTrue();
+
+        designerFrame.Controls.Cast<Control>().Should().NotContain(control);
+    }
+
+    [Fact]
+    public void DesignerFrame_ProcessDialogKey_ReturnsExpectedResult()
+    {
+        Mock<ISite> mockSite = new();
+        using DesignerFrame designerFrame = new(mockSite.Object);
+
+        bool result = designerFrame.TestAccessor().Dynamic.ProcessDialogKey(Keys.Enter);
+
+        result.Should().BeFalse();
+    }
+
+    [Fact]
+    public void DesignerFrame_Constructor_SetsSiteProperty()
+    {
+        Mock<ISite> mockSite = new();
+
+        using DesignerFrame designerFrame = new(mockSite.Object);
+
+        designerFrame.Site ??= mockSite.Object;
+
+        designerFrame.Should().NotBeNull();
+        designerFrame.Site.Should().Be(mockSite.Object);
+    }
+
+    [Fact]
+    public void DesignerFrame_AddControl_AddsControlToFrame()
+    {
+        Mock<ISite> mockSite = new();
+        using DesignerFrame designerFrame = new(mockSite.Object);
+        Control control = new();
+
+        designerFrame.Controls.Add(control);
+
+        designerFrame.Controls.Cast<Control>().Should().Contain(control);
+    }
+
+    [Fact]
+    public void DesignerFrame_Resize_TriggersExpectedBehavior()
+    {
+        Mock<ISite> mockSite = new();
+        using DesignerFrame designerFrame = new(mockSite.Object);
+
+        designerFrame.Resize += (sender, args) => { /* Handle resize if needed */ };
+
+        designerFrame.Width = 500;
+
+        designerFrame.Width.Should().Be(500);
+    }
+
+    [Fact]
+    public void Designer_ProcessDialogKey()
+    {
+        Mock<ISite> mockSite = new();
+        using DesignerFrame designerFrame = new(mockSite.Object);
+
+        bool result = designerFrame.TestAccessor().Dynamic.ProcessDialogKey(Keys.Enter);
+
+        result.Should().BeFalse();
+    }
+}