chore: import upstream snapshot with attribution

dotnet/tests/Microsoft.Agents.AI.Workflows.UnitTests/PortableValueTests.cs

@@ -0,0 +1,130 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.Diagnostics.CodeAnalysis;
+using System.Threading.Tasks;
+using FluentAssertions;
+using Microsoft.Agents.AI.Workflows.Checkpointing;
+using Microsoft.Extensions.AI;
+
+namespace Microsoft.Agents.AI.Workflows.UnitTests;
+
+public class PortableValueTests
+{
+    [SuppressMessage("Performance", "CA1812", Justification = "This is used as a Never/Bottom type.")]
+    private sealed class Never
+    {
+        private Never() { }
+    }
+
+    [Theory]
+    [InlineData("string")]
+    [InlineData(42)]
+    [InlineData(true)]
+    [InlineData(3.14)]
+    public async Task Test_PortableValueRoundtripAsync<T>(T value)
+    {
+        value.Should().NotBeNull();
+
+        PortableValue portableValue = new(value);
+
+        portableValue.Is<Never>(out _).Should().BeFalse();
+        portableValue.Is(out T? returnedValue).Should().BeTrue();
+        returnedValue.Should().Be(value);
+    }
+
+    [Fact]
+    public async Task Test_PortableValueRoundtripObjectAsync()
+    {
+        ChatMessage value = new(ChatRole.User, "Hello?");
+
+        PortableValue portableValue = new(value);
+
+        portableValue.Is<Never>(out _).Should().BeFalse();
+        portableValue.Is(out ChatMessage? returnedValue).Should().BeTrue();
+        returnedValue.Should().Be(value);
+    }
+
+    [Theory]
+    [InlineData("string")]
+    [InlineData(42)]
+    [InlineData(true)]
+    [InlineData(3.14)]
+    public async Task Test_DelayedSerializationRoundtripAsync<T>(T value)
+    {
+        value.Should().NotBeNull();
+
+        TestDelayedDeserialization<T> delayed = new(value);
+        PortableValue portableValue = new(delayed);
+
+        portableValue.Is<Never>(out _).Should().BeFalse();
+        portableValue.Is(out object? obj).Should().BeTrue();
+        obj.Should().NotBeOfType<T>();
+        obj.Should().BeOfType<PortableValue>()
+                .And.Subject.As<PortableValue>()
+                            .As<T>().Should().Be(value);
+
+        portableValue.Is(out T? returnedValue).Should().BeTrue();
+        returnedValue.Should().Be(value);
+    }
+
+    [Fact]
+    public async Task Test_DelayedSerializationRoundtripObjectAsync()
+    {
+        ChatMessage value = new(ChatRole.User, "Hello?");
+
+        TestDelayedDeserialization<ChatMessage> delayed = new(value);
+        PortableValue portableValue = new(delayed);
+
+        portableValue.Is<Never>(out _).Should().BeFalse();
+        portableValue.Is(out object? obj).Should().BeTrue();
+        obj.Should().NotBeOfType<ChatMessage>();
+        obj.Should().BeOfType<PortableValue>()
+                .And.Subject.As<PortableValue>()
+                            .As<ChatMessage>().Should().Be(value);
+
+        portableValue.Is(out ChatMessage? returnedValue).Should().BeTrue();
+        returnedValue.Should().Be(value);
+    }
+
+    private sealed class TestDelayedDeserialization<T> : IDelayedDeserialization
+    {
+        [NotNull]
+        public T Value { get; }
+
+        public TestDelayedDeserialization([DisallowNull] T value)
+        {
+            this.Value = value;
+        }
+
+        public TValue Deserialize<TValue>()
+        {
+            if (typeof(TValue) == typeof(object))
+            {
+                return (TValue)(object)new PortableValue(this.Value);
+            }
+
+            if (this.Value is TValue value)
+            {
+                return value;
+            }
+
+            throw new InvalidOperationException();
+        }
+
+        public object? Deserialize(Type targetType)
+        {
+            if (targetType == typeof(object))
+            {
+                return new PortableValue(this.Value);
+            }
+
+            if (targetType.IsInstanceOfType(this.Value))
+            {
+                return this.Value;
+            }
+
+            return null;
+        }
+    }
+}