chore: import upstream snapshot with attribution

dotnet/tests/Microsoft.Agents.AI.Hosting.OpenAI.UnitTests/InMemoryResponsesServiceTests.cs

@@ -0,0 +1,102 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.Collections.Generic;
+using System.Runtime.CompilerServices;
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.Agents.AI.Hosting.OpenAI.Conversations;
+using Microsoft.Agents.AI.Hosting.OpenAI.Conversations.Models;
+using Microsoft.Agents.AI.Hosting.OpenAI.Responses;
+using Microsoft.Agents.AI.Hosting.OpenAI.Responses.Models;
+using Microsoft.Extensions.AI;
+
+namespace Microsoft.Agents.AI.Hosting.OpenAI.UnitTests;
+
+/// <summary>
+/// Unit tests for <see cref="InMemoryResponsesService"/> request validation.
+/// </summary>
+public sealed class InMemoryResponsesServiceTests
+{
+    [Fact]
+    public async Task ValidateRequestAsync_NonexistentConversation_ReturnsNotFoundErrorAsync()
+    {
+        // Arrange
+        using var storage = new InMemoryConversationStorage();
+        using var service = new InMemoryResponsesService(
+            new StubResponseExecutor(), new InMemoryStorageOptions(), storage);
+        var request = new CreateResponse
+        {
+            Input = ResponseInput.FromText("hello"),
+            Conversation = ConversationReference.FromId("conv_does_not_exist")
+        };
+
+        // Act
+        ResponseError? error = await service.ValidateRequestAsync(request);
+
+        // Assert
+        Assert.NotNull(error);
+        Assert.Equal("conversation_not_found", error.Code);
+    }
+
+    [Fact]
+    public async Task ValidateRequestAsync_ExistingConversation_ReturnsNullAsync()
+    {
+        // Arrange
+        using var storage = new InMemoryConversationStorage();
+        var conversation = new Conversation
+        {
+            Id = "conv_" + Guid.NewGuid().ToString("N"),
+            CreatedAt = DateTimeOffset.UtcNow.ToUnixTimeSeconds()
+        };
+        await storage.CreateConversationAsync(conversation);
+        using var service = new InMemoryResponsesService(
+            new StubResponseExecutor(), new InMemoryStorageOptions(), storage);
+        var request = new CreateResponse
+        {
+            Input = ResponseInput.FromText("hello"),
+            Conversation = ConversationReference.FromId(conversation.Id)
+        };
+
+        // Act
+        ResponseError? error = await service.ValidateRequestAsync(request);
+
+        // Assert
+        Assert.Null(error);
+    }
+
+    [Fact]
+    public async Task ValidateRequestAsync_ConversationSuppliedButNoStorage_ReturnsNullAsync()
+    {
+        // Arrange - without a conversation store there is no existence to verify.
+        using var service = new InMemoryResponsesService(
+            new StubResponseExecutor(), new InMemoryStorageOptions());
+        var request = new CreateResponse
+        {
+            Input = ResponseInput.FromText("hello"),
+            Conversation = ConversationReference.FromId("conv_does_not_exist")
+        };
+
+        // Act
+        ResponseError? error = await service.ValidateRequestAsync(request);
+
+        // Assert
+        Assert.Null(error);
+    }
+
+    private sealed class StubResponseExecutor : IResponseExecutor
+    {
+        public ValueTask<ResponseError?> ValidateRequestAsync(CreateResponse request, CancellationToken cancellationToken = default)
+            => ValueTask.FromResult<ResponseError?>(null);
+
+        public async IAsyncEnumerable<StreamingResponseEvent> ExecuteAsync(
+            AgentInvocationContext context,
+            CreateResponse request,
+            IReadOnlyList<ChatMessage>? conversationHistory = null,
+            [EnumeratorCancellation] CancellationToken cancellationToken = default)
+        {
+            await Task.CompletedTask.ConfigureAwait(false);
+            yield break;
+        }
+    }
+}