Add trimming tests for System.ComponentModel.TypeConverter changes

src/libraries/System.ComponentModel.TypeConverter/src/System/ComponentModel/TypeDescriptor.cs

@@ -8,7 +8,6 @@
 using System.Diagnostics;
 using System.Diagnostics.CodeAnalysis;
 using System.Globalization;
-using System.Linq;
 using System.Reflection;
 using System.Threading;
 
@@ -325,7 +324,7 @@ private static void CheckDefaultProvider(Type type)
             // own cache state against the type. There shouldn't be
             // more than one of these, but walk anyway. Walk in
             // reverse order so that the most derived takes precidence.
-            object[] attrs = type.GetCustomAttributes(typeof(TypeDescriptionProviderAttribute), false).ToArray();
+            object[] attrs = type.GetCustomAttributes(typeof(TypeDescriptionProviderAttribute), false);
             bool providerAdded = false;
             for (int idx = attrs.Length - 1; idx >= 0; idx--)
             {

src/libraries/System.ComponentModel.TypeConverter/tests/TrimmingTests/ComObjectTypeTest.cs

@@ -0,0 +1,22 @@
+using System;
+using System.ComponentModel;
+
+/// <summary>
+/// Tests that the System.ComponentModel.TypeDescriptor.ComObjectType
+/// property works as expected when used in a trimmed application.
+/// </summary>
+class Program
+{
+    static int Main(string[] args)
+    {
+        Type type = TypeDescriptor.ComObjectType;
+
+        // Tests that the ctor for System.ComponentModel.TypeDescriptor+TypeDescriptorComObject is not trimmed out.
+        object obj = Activator.CreateInstance(type);
+        string expectedObjTypeNamePrefix = "System.ComponentModel.TypeDescriptor+TypeDescriptorComObject, System.ComponentModel.TypeConverter, Version=";
+
+        return obj != null && obj.GetType().AssemblyQualifiedName.StartsWith(expectedObjTypeNamePrefix)
+            ? 100
+            : -1;
+    }
+}

src/libraries/System.ComponentModel.TypeConverter/tests/TrimmingTests/System.ComponentModel.TypeConverter.TrimmingTests.proj

@@ -0,0 +1,5 @@
+<Project DefaultTargets="Build">
+  <Import Project="$([MSBuild]::GetPathOfFileAbove(Directory.Build.props))" />
+
+  <Import Project="$([MSBuild]::GetPathOfFileAbove(Directory.Build.targets))" />
+</Project>

src/libraries/System.ObjectModel/tests/TrimmingTests/System.ObjectModel.TrimmingTests.proj

@@ -0,0 +1,5 @@
+<Project DefaultTargets="Build">
+  <Import Project="$([MSBuild]::GetPathOfFileAbove(Directory.Build.props))" />
+
+  <Import Project="$([MSBuild]::GetPathOfFileAbove(Directory.Build.targets))" />
+</Project>

src/libraries/System.ObjectModel/tests/TrimmingTests/TypeDescriptionProviderAttributeCtorTest.cs

@@ -0,0 +1,52 @@
+using System;
+using System.ComponentModel;
+using System.Xml.Linq;
+
+class Program
+{
+    /// <summary>
+    /// Tests that the public parameterless constructors of types passed to the
+    /// constructors of System.ComponentModel.TypeDescriptionProviderAttribute
+    /// property are preserved when needed in a trimmed application.
+    /// </summary>
+    static int Main(string[] args)
+    {
+        TypeDescriptionProviderAttribute attr = new TypeDescriptionProviderAttribute("Program+MyTypeDescriptionProvider");
+        if (!RunTest(attr))
+        {
+            return -1;
+        }
+
+        attr = new TypeDescriptionProviderAttribute(typeof(MyOtherTypeDescriptionProvider));
+        if (!RunTest(attr))
+        {
+            return -1;
+        }
+
+        return 100;
+    }
+
+    private static bool RunTest(TypeDescriptionProviderAttribute attr)
+    {
+        Type providerType = Type.GetType(attr.TypeName);
+
+        if (providerType != null && typeof(TypeDescriptionProvider).IsAssignableFrom(providerType))
+        {
+            TypeDescriptionProvider provider = (TypeDescriptionProvider)Activator.CreateInstance(providerType);
+            if (provider == null)
+            {
+                return false;
+            }
+        }
+        else
+        {
+            return false;
+        }
+
+        return true;
+    }
+
+    private class MyTypeDescriptionProvider : TypeDescriptionProvider { }
+
+    private class MyOtherTypeDescriptionProvider : TypeDescriptionProvider { }
+}

src/libraries/System.Runtime/tests/TrimmingTests/DefaultValueAttributeCtorTest.cs

@@ -0,0 +1,34 @@
+using System;
+using System.ComponentModel;
+using System.Globalization;
+
+/// <summary>
+/// Tests that System.ComponentModel.TypeConverter.ConvertFromInvariantString
+/// is not trimmed out when needed by DefaultValueAttribute in a trimmed application.
+/// </summary>
+class Program
+{
+    static int Main(string[] args)
+    {
+        TypeDescriptor.AddAttributes(typeof(string), new TypeConverterAttribute(typeof(MyStringConverter)));
+
+        var attribute = new DefaultValueAttribute(typeof(string), "Hello, world!");
+        return (string)attribute.Value == "Hello, world!trivia" ? 100 : -1;
+    }
+
+    private class MyStringConverter : StringConverter
+    {
+        /// <summary>
+        /// Converts the specified value object to a string object.
+        /// </summary>
+        public override object ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, object value)
+        {
+            if (value is string)
+            {
+                return (string)value + "trivia";
+            }
+
+            throw new NotSupportedException();
+        }
+    }
+}