chore: import upstream snapshot with attribution

dotnet/tests/Microsoft.Agents.AI.A2A.UnitTests/Extensions/ChatMessageExtensionsTests.cs

@@ -0,0 +1,87 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System.Collections.Generic;
+using A2A;
+using Microsoft.Extensions.AI;
+
+namespace Microsoft.Agents.AI.A2A.UnitTests;
+
+/// <summary>
+/// Unit tests for the <see cref="ChatMessageExtensions"/> class.
+/// </summary>
+public sealed class ChatMessageExtensionsTests
+{
+    [Fact]
+    public void ToA2AMessage_WithMessageContainingMultipleContents_AddsAllContentsAsParts()
+    {
+        // Arrange
+        var contents = new List<AIContent>
+        {
+            new UriContent("https://example.com/report.pdf", "file/pdf"),
+            new TextContent("please summarize the file content"),
+            new TextContent("and send it to me over email")
+        };
+        var chatMessage = new ChatMessage(ChatRole.User, contents);
+        var messages = new List<ChatMessage> { chatMessage };
+
+        // Act
+        var a2aMessage = messages.ToA2AMessage();
+
+        // Assert
+        Assert.NotNull(a2aMessage);
+        Assert.NotNull(a2aMessage.MessageId);
+        Assert.NotEmpty(a2aMessage.MessageId);
+
+        Assert.Equal(Role.User, a2aMessage.Role);
+
+        Assert.NotNull(a2aMessage.Parts);
+        Assert.Equal(3, a2aMessage.Parts.Count);
+
+        Assert.Equal(PartContentCase.Url, a2aMessage.Parts[0].ContentCase);
+        Assert.Equal("https://example.com/report.pdf", a2aMessage.Parts[0].Url);
+
+        Assert.Equal(PartContentCase.Text, a2aMessage.Parts[1].ContentCase);
+        Assert.Equal("please summarize the file content", a2aMessage.Parts[1].Text);
+
+        Assert.Equal(PartContentCase.Text, a2aMessage.Parts[2].ContentCase);
+        Assert.Equal("and send it to me over email", a2aMessage.Parts[2].Text);
+    }
+
+    [Fact]
+    public void ToA2AMessage_WithMixedMessages_AddsAllContentsAsParts()
+    {
+        // Arrange
+        var firstMessage = new ChatMessage(ChatRole.User, [
+            new UriContent("https://example.com/report.pdf", "file/pdf"),
+        ]);
+        var secondMessage = new ChatMessage(ChatRole.User, [
+            new TextContent("please summarize the file content")
+        ]);
+        var thirdMessage = new ChatMessage(ChatRole.User, [
+            new TextContent("and send it to me over email")
+        ]);
+        var messages = new List<ChatMessage> { firstMessage, secondMessage, thirdMessage };
+
+        // Act
+        var a2aMessage = messages.ToA2AMessage();
+
+        // Assert
+        Assert.NotNull(a2aMessage);
+        Assert.NotNull(a2aMessage.MessageId);
+        Assert.NotEmpty(a2aMessage.MessageId);
+
+        Assert.Equal(Role.User, a2aMessage.Role);
+
+        Assert.NotNull(a2aMessage.Parts);
+        Assert.Equal(3, a2aMessage.Parts.Count);
+
+        Assert.Equal(PartContentCase.Url, a2aMessage.Parts[0].ContentCase);
+        Assert.Equal("https://example.com/report.pdf", a2aMessage.Parts[0].Url);
+
+        Assert.Equal(PartContentCase.Text, a2aMessage.Parts[1].ContentCase);
+        Assert.Equal("please summarize the file content", a2aMessage.Parts[1].Text);
+
+        Assert.Equal(PartContentCase.Text, a2aMessage.Parts[2].ContentCase);
+        Assert.Equal("and send it to me over email", a2aMessage.Parts[2].Text);
+    }
+}