Add code coverage for RadioButtonRenderer

src/test/unit/System.Windows.Forms/System/Windows/Forms/RadioButtonRendererTests.cs

@@ -1,8 +1,6 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
-#nullable disable
-
 using System.Drawing;
 using System.Runtime.InteropServices;
 using System.Windows.Forms.Metafiles;
@@ -157,5 +155,234 @@ public void RadioButtonRenderer_DrawRadioButton_OverloadWithHandle(bool focus)
             );
     }
 
+    [WinFormsTheory]
+    [InlineData(RadioButtonState.CheckedNormal)]
+    [InlineData(RadioButtonState.CheckedPressed)]
+    [InlineData(RadioButtonState.CheckedDisabled)]
+    [InlineData(RadioButtonState.UncheckedNormal)]
+    [InlineData(RadioButtonState.UncheckedPressed)]
+    [InlineData(RadioButtonState.UncheckedDisabled)]
+    public void IsBackgroundPartiallyTransparent_ReturnsExpected(RadioButtonState state)
+    {
+        bool original = RadioButtonRenderer.RenderMatchingApplicationState;
+
+        try
+        {
+            RadioButtonRenderer.RenderMatchingApplicationState = false;
+            bool resultWithVisualStyles = RadioButtonRenderer.IsBackgroundPartiallyTransparent(state);
+
+            RadioButtonRenderer.RenderMatchingApplicationState = true;
+            bool resultWithoutVisualStyles = RadioButtonRenderer.IsBackgroundPartiallyTransparent(state);
+
+            if (Application.RenderWithVisualStyles)
+            {
+                resultWithVisualStyles.Should().BeTrue();
+            }
+            else
+            {
+                resultWithVisualStyles.Should().BeFalse();
+            }
+
+            if (!Application.RenderWithVisualStyles)
+            {
+                resultWithoutVisualStyles.Should().BeFalse();
+            }
+        }
+        finally
+        {
+            RadioButtonRenderer.RenderMatchingApplicationState = original;
+        }
+    }
+
+    [WinFormsFact]
+    public void DrawParentBackground_DoesNotThrow_WhenVisualStylesDisabled()
+    {
+        using Form parent = new();
+        using Panel child = new();
+        parent.Controls.Add(child);
+        parent.Show();
+
+        using Bitmap bmp = new(10, 10);
+        using Graphics g = Graphics.FromImage(bmp);
+
+        bool original = RadioButtonRenderer.RenderMatchingApplicationState;
+        try
+        {
+            RadioButtonRenderer.RenderMatchingApplicationState = true;
+            RadioButtonRenderer.DrawParentBackground(g, new Rectangle(0, 0, 10, 10), child);
+        }
+        finally
+        {
+            RadioButtonRenderer.RenderMatchingApplicationState = original;
+        }
+    }
+
+    [WinFormsFact]
+    public void DrawParentBackground_CallsRenderer_WhenVisualStylesEnabled()
+    {
+        using Form parent = new();
+        using Panel child = new();
+        parent.Controls.Add(child);
+        parent.Show();
+
+        using Bitmap bmp = new(10, 10);
+        using Graphics g = Graphics.FromImage(bmp);
+
+        bool original = RadioButtonRenderer.RenderMatchingApplicationState;
+        try
+        {
+            RadioButtonRenderer.RenderMatchingApplicationState = false;
+            RadioButtonRenderer.DrawParentBackground(g, new Rectangle(0, 0, 10, 10), child);
+        }
+        finally
+        {
+            RadioButtonRenderer.RenderMatchingApplicationState = original;
+        }
+    }
+
+    [WinFormsFact]
+    public void DrawRadioButton_WithImage_Overload_CallsMainOverload()
+    {
+        using Form form = new();
+        using RadioButton control = (RadioButton)CreateButton();
+        form.Controls.Add(control);
+        form.Show();
+
+        using Bitmap bmp = new(20, 20);
+        using Graphics g = Graphics.FromImage(bmp);
+        using Image image = new Bitmap(10, 10);
+
+        Point glyphLocation = new(2, 2);
+        Rectangle textBounds = new(5, 5, 30, 15);
+        Rectangle imageBounds = new(7, 7, 10, 10);
+        string radioButtonText = "Radio";
+        Font font = SystemFonts.DefaultFont;
+        bool focused = false;
+        RadioButtonState state = RadioButtonState.CheckedNormal;
+
+        RadioButtonRenderer.DrawRadioButton(
+            g,
+            glyphLocation,
+            textBounds,
+            radioButtonText,
+            font,
+            image,
+            imageBounds,
+            focused,
+            state
+        );
+    }
+
+    [WinFormsFact]
+    public void DrawRadioButton_WithImage_Overload_AllowsNullTextAndFont()
+    {
+        using Bitmap bmp = new(20, 20);
+        using Graphics g = Graphics.FromImage(bmp);
+        using Image image = new Bitmap(10, 10);
+
+        Point glyphLocation = new(0, 0);
+        Rectangle textBounds = new(0, 0, 10, 10);
+        Rectangle imageBounds = new(0, 0, 10, 10);
+        bool focused = false;
+        RadioButtonState state = RadioButtonState.UncheckedNormal;
+
+        RadioButtonRenderer.DrawRadioButton(
+            g,
+            glyphLocation,
+            textBounds,
+            null,
+            null,
+            image,
+            imageBounds,
+            focused,
+            state
+        );
+    }
+
+    [WinFormsTheory]
+    [InlineData(RadioButtonState.CheckedNormal)]
+    [InlineData(RadioButtonState.CheckedPressed)]
+    [InlineData(RadioButtonState.UncheckedNormal)]
+    [InlineData(RadioButtonState.UncheckedPressed)]
+    public void GetGlyphSize_ReturnsExpectedSize(RadioButtonState state)
+    {
+        using Bitmap bmp = new(20, 20);
+        using Graphics g = Graphics.FromImage(bmp);
+
+        Size size = RadioButtonRenderer.GetGlyphSize(g, state);
+
+        if (Application.RenderWithVisualStyles)
+        {
+            size.Width.Should().BeGreaterThan(0);
+            size.Height.Should().BeGreaterThan(0);
+        }
+        else
+        {
+            size.Should().Be(new Size(13, 13));
+        }
+    }
+
+    [WinFormsFact]
+    public void DrawRadioButton_Internal_WithImageAndText_DoesNotThrow()
+    {
+        using Bitmap bmp = new(30, 30);
+        using Graphics g = Graphics.FromImage(bmp);
+        using Image image = new Bitmap(10, 10);
+
+        Point glyphLocation = new(1, 1);
+        Rectangle textBounds = new(12, 1, 15, 15);
+        Rectangle imageBounds = new(2, 2, 10, 10);
+        string radioButtonText = "Test";
+        Font font = SystemFonts.DefaultFont;
+        TextFormatFlags flags = TextFormatFlags.Default;
+        bool focused = true;
+        RadioButtonState state = RadioButtonState.CheckedNormal;
+        HWND hwnd = HWND.Null;
+
+        typeof(RadioButtonRenderer)
+            .TestAccessor()
+            .Dynamic
+            .DrawRadioButton(
+                g,
+                glyphLocation,
+                textBounds,
+                radioButtonText,
+                font,
+                flags,
+                image,
+                imageBounds,
+                focused,
+                state,
+                hwnd
+            );
+    }
+
+    [Theory]
+    [InlineData(RadioButtonState.CheckedNormal, ButtonState.Checked)]
+    [InlineData(RadioButtonState.CheckedHot, ButtonState.Checked)]
+    [InlineData(RadioButtonState.CheckedPressed, ButtonState.Checked | ButtonState.Pushed)]
+    [InlineData(RadioButtonState.CheckedDisabled, ButtonState.Checked | ButtonState.Inactive)]
+    [InlineData(RadioButtonState.UncheckedPressed, ButtonState.Pushed)]
+    [InlineData(RadioButtonState.UncheckedDisabled, ButtonState.Inactive)]
+    [InlineData(RadioButtonState.UncheckedNormal, ButtonState.Normal)]
+    public void ConvertToButtonState_ReturnsExpected(RadioButtonState radioState, ButtonState expected)
+    {
+        RadioButtonRenderer.ConvertToButtonState(radioState).Should().Be(expected);
+    }
+
+    [Theory]
+    [InlineData(ButtonState.Checked, false, RadioButtonState.CheckedNormal)]
+    [InlineData(ButtonState.Checked, true, RadioButtonState.CheckedHot)]
+    [InlineData(ButtonState.Checked | ButtonState.Pushed, false, RadioButtonState.CheckedPressed)]
+    [InlineData(ButtonState.Checked | ButtonState.Inactive, false, RadioButtonState.CheckedDisabled)]
+    [InlineData(ButtonState.Pushed, false, RadioButtonState.UncheckedPressed)]
+    [InlineData(ButtonState.Inactive, false, RadioButtonState.UncheckedDisabled)]
+    [InlineData(ButtonState.Normal, false, RadioButtonState.UncheckedNormal)]
+    [InlineData(ButtonState.Normal, true, RadioButtonState.UncheckedHot)]
+    public void ConvertFromButtonState_ReturnsExpected(ButtonState buttonState, bool isHot, RadioButtonState expected)
+    {
+        RadioButtonRenderer.ConvertFromButtonState(buttonState, isHot).Should().Be(expected);
+    }
+
     protected override ButtonBase CreateButton() => new RadioButton();
 }