Add test coverage for TextBox

src/System.Windows.Forms/tests/UnitTests/System/Windows/Forms/TextBoxRendererTests.cs

@@ -0,0 +1,95 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System.Drawing;
+using System.Windows.Forms.VisualStyles;
+
+namespace System.Windows.Forms.Tests;
+
+public class TextBoxRendererTests
+{
+    [WinFormsTheory]
+    [InlineData(TextBoxState.Normal)]
+    [InlineData(TextBoxState.Hot)]
+    [InlineData(TextBoxState.Selected)]
+    [InlineData(TextBoxState.Disabled)]
+    public void TextBoxRenderer_DrawTextBox(TextBoxState state)
+    {
+        using Bitmap bitmap = new(100, 100);
+        using Graphics graphics = Graphics.FromImage(bitmap);
+        Rectangle bounds = new Rectangle(10, 20, 30, 40);
+
+        TextBoxRenderer.DrawTextBox(graphics, bounds, state);
+    }
+
+    [WinFormsTheory]
+    [InlineData(TextBoxState.Normal)]
+    [InlineData(TextBoxState.Hot)]
+    [InlineData(TextBoxState.Selected)]
+    [InlineData(TextBoxState.Disabled)]
+    public void TextBoxRenderer_DrawTextBox_OverloadWithTextAndFont(TextBoxState state)
+    {
+        using Bitmap bitmap = new(100, 100);
+        using Graphics graphics = Graphics.FromImage(bitmap);
+        Rectangle bounds = new Rectangle(10, 20, 30, 40);
+
+        TextBoxRenderer.DrawTextBox(graphics, bounds, "text", SystemFonts.DefaultFont, state);
+    }
+
+    [WinFormsTheory]
+    [InlineData(TextBoxState.Normal)]
+    [InlineData(TextBoxState.Hot)]
+    [InlineData(TextBoxState.Selected)]
+    [InlineData(TextBoxState.Disabled)]
+    public void TextBoxRenderer_DrawTextBox_OverloadWithTextFontAndTextBounds(TextBoxState state)
+    {
+        using Bitmap bitmap = new(100, 100);
+        using Graphics graphics = Graphics.FromImage(bitmap);
+        Rectangle bounds = new Rectangle(10, 20, 30, 40);
+        Rectangle textBounds = new Rectangle(10, 20, 30, 40);
+
+        TextBoxRenderer.DrawTextBox(graphics, bounds, "text", SystemFonts.DefaultFont, textBounds, state);
+    }
+
+    public static IEnumerable<object[]> DrawTextBox_FlagsAndState_TestData()
+    {
+        yield return new object[] { TextBoxState.Normal, TextFormatFlags.Default };
+        yield return new object[] { TextBoxState.Normal, TextFormatFlags.TextBoxControl };
+        yield return new object[] { TextBoxState.Normal, TextFormatFlags.PreserveGraphicsTranslateTransform };
+
+        yield return new object[] { TextBoxState.Hot, TextFormatFlags.Default };
+        yield return new object[] { TextBoxState.Hot, TextFormatFlags.TextBoxControl };
+        yield return new object[] { TextBoxState.Hot, TextFormatFlags.PreserveGraphicsTranslateTransform };
+
+        yield return new object[] { TextBoxState.Disabled, TextFormatFlags.Default };
+        yield return new object[] { TextBoxState.Disabled, TextFormatFlags.TextBoxControl };
+        yield return new object[] { TextBoxState.Disabled, TextFormatFlags.PreserveGraphicsTranslateTransform };
+
+        yield return new object[] { TextBoxState.Selected, TextFormatFlags.Default };
+        yield return new object[] { TextBoxState.Selected, TextFormatFlags.TextBoxControl };
+        yield return new object[] { TextBoxState.Selected, TextFormatFlags.PreserveGraphicsTranslateTransform };
+    }
+
+    [WinFormsTheory]
+    [MemberData(nameof(DrawTextBox_FlagsAndState_TestData))]
+    public void TextBoxRenderer_DrawTextBox_OverloadWithTextFontAndFlags(TextFormatFlags flag, TextBoxState state)
+    {
+        using Bitmap bitmap = new(100, 100);
+        using Graphics graphics = Graphics.FromImage(bitmap);
+        Rectangle bounds = new Rectangle(10, 20, 30, 40);
+
+        TextBoxRenderer.DrawTextBox(graphics, bounds, "text", SystemFonts.DefaultFont, flag, state);
+    }
+
+    [WinFormsTheory]
+    [MemberData(nameof(DrawTextBox_FlagsAndState_TestData))]
+    public void TextBoxRenderer_DrawTextBox_OverloadWithTextFontTextboundsAndFlags(TextFormatFlags flag, TextBoxState state)
+    {
+        using Bitmap bitmap = new(100, 100);
+        using Graphics graphics = Graphics.FromImage(bitmap);
+        Rectangle bounds = new Rectangle(10, 20, 30, 40);
+        Rectangle textBounds = new Rectangle(10, 20, 30, 40);
+
+        TextBoxRenderer.DrawTextBox(graphics, bounds, "text", SystemFonts.DefaultFont, textBounds, flag, state);
+    }
+}

src/System.Windows.Forms/tests/UnitTests/TextBoxTests.cs

@@ -257,6 +257,41 @@ public void TextBox_ImeModeBase_GetWithHandle_ReturnsExpected()
         Assert.Equal(0, createdCallCount);
     }
 
+    [WinFormsTheory]
+    [InvalidEnumData<AutoCompleteMode>]
+    public void TextBox_AutoCompleteMode_SetInvalidValue_ThrowsInvalidEnumArgumentException(AutoCompleteMode value)
+    {
+        using SubTextBox control = new();
+
+        Action act = () => control.AutoCompleteMode = value;
+        act.Should().Throw<InvalidEnumArgumentException>().And.ParamName.Should().Be("value");
+    }
+
+    [WinFormsTheory]
+    [EnumData<AutoCompleteSource>]
+    public void TextBox_AutoCompleteSource_Set_GetReturnsExpected(AutoCompleteSource value)
+    {
+        using SubTextBox control = new()
+        {
+            AutoCompleteSource = value == AutoCompleteSource.ListItems ? AutoCompleteSource.None : value
+        };
+
+        if(value != AutoCompleteSource.ListItems)
+        {
+            control.AutoCompleteSource.Should().Be(value);
+        }         
+    }
+
+    [WinFormsTheory]
+    [InvalidEnumData<AutoCompleteSource>]
+    public void TextBox_AutoCompleteSource_InvalidAutoCompleteSource_ThrowsInvalidEnumArgumentException(AutoCompleteSource source)
+    {
+        using SubTextBox control = new();
+
+        Action act = () => control.AutoCompleteSource = source;
+        act.Should().Throw<InvalidEnumArgumentException>().And.ParamName.Should().Be("value");
+    }
+
     [WinFormsFact]
     public void TextBox_PasswordChar_GetWithoutHandle_ReturnsExpected()
     {