test

dotnet/tests/Microsoft.Agents.AI.A2A.UnitTests/A2AContinuationTokenTests.cs

@@ -0,0 +1,152 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.Text.Json;
+using Microsoft.Extensions.AI;
+
+namespace Microsoft.Agents.AI.A2A.UnitTests;
+
+/// <summary>
+/// Unit tests for the <see cref="A2AContinuationToken"/> class.
+/// </summary>
+public sealed class A2AContinuationTokenTests
+{
+    [Fact]
+    public void Constructor_WithValidTaskId_InitializesTaskIdProperty()
+    {
+        // Arrange
+        const string TaskId = "task-123";
+
+        // Act
+        var token = new A2AContinuationToken(TaskId);
+
+        // Assert
+        Assert.Equal(TaskId, token.TaskId);
+    }
+
+    [Fact]
+    public void ToBytes_WithValidToken_SerializesToJsonBytes()
+    {
+        // Arrange
+        const string TaskId = "task-456";
+        var token = new A2AContinuationToken(TaskId);
+
+        // Act
+        var bytes = token.ToBytes();
+
+        // Assert
+        Assert.NotEqual(0, bytes.Length);
+        var jsonString = System.Text.Encoding.UTF8.GetString(bytes.ToArray());
+        using var jsonDoc = JsonDocument.Parse(jsonString);
+        var root = jsonDoc.RootElement;
+        Assert.True(root.TryGetProperty("taskId", out var taskIdElement));
+        Assert.Equal(TaskId, taskIdElement.GetString());
+    }
+
+    [Fact]
+    public void FromToken_WithA2AContinuationToken_ReturnsSameInstance()
+    {
+        // Arrange
+        const string TaskId = "task-direct";
+        var originalToken = new A2AContinuationToken(TaskId);
+
+        // Act
+        var resultToken = A2AContinuationToken.FromToken(originalToken);
+
+        // Assert
+        Assert.Same(originalToken, resultToken);
+        Assert.Equal(TaskId, resultToken.TaskId);
+    }
+
+    [Fact]
+    public void FromToken_WithSerializedToken_DeserializesCorrectly()
+    {
+        // Arrange
+        const string TaskId = "task-deserialized";
+        var originalToken = new A2AContinuationToken(TaskId);
+        var serialized = originalToken.ToBytes();
+
+        // Create a mock token wrapper to pass to FromToken
+        var mockToken = new MockResponseContinuationToken(serialized);
+
+        // Act
+        var resultToken = A2AContinuationToken.FromToken(mockToken);
+
+        // Assert
+        Assert.Equal(TaskId, resultToken.TaskId);
+        Assert.IsType<A2AContinuationToken>(resultToken);
+    }
+
+    [Fact]
+    public void FromToken_RoundTrip_PreservesTaskId()
+    {
+        // Arrange
+        const string TaskId = "task-roundtrip-123";
+        var originalToken = new A2AContinuationToken(TaskId);
+        var serialized = originalToken.ToBytes();
+        var mockToken = new MockResponseContinuationToken(serialized);
+
+        // Act
+        var deserializedToken = A2AContinuationToken.FromToken(mockToken);
+        var reserialized = deserializedToken.ToBytes();
+        var mockToken2 = new MockResponseContinuationToken(reserialized);
+        var deserializedAgain = A2AContinuationToken.FromToken(mockToken2);
+
+        // Assert
+        Assert.Equal(TaskId, deserializedAgain.TaskId);
+    }
+
+    [Fact]
+    public void FromToken_WithEmptyData_ThrowsArgumentException()
+    {
+        // Arrange
+        var emptyToken = new MockResponseContinuationToken(ReadOnlyMemory<byte>.Empty);
+
+        // Act & Assert
+        Assert.Throws<ArgumentException>(() => A2AContinuationToken.FromToken(emptyToken));
+    }
+
+    [Fact]
+    public void FromToken_WithMissingTaskIdProperty_ThrowsException()
+    {
+        // Arrange
+        var jsonWithoutTaskId = System.Text.Encoding.UTF8.GetBytes("{ \"someOtherProperty\": \"value\" }").AsMemory();
+        var mockToken = new MockResponseContinuationToken(jsonWithoutTaskId);
+
+        // Act & Assert
+        Assert.Throws<JsonException>(() => A2AContinuationToken.FromToken(mockToken));
+    }
+
+    [Fact]
+    public void FromToken_WithValidTaskId_ParsesTaskIdCorrectly()
+    {
+        // Arrange
+        const string TaskId = "task-multi-prop";
+        var json = System.Text.Encoding.UTF8.GetBytes($"{{ \"taskId\": \"{TaskId}\" }}").AsMemory();
+        var mockToken = new MockResponseContinuationToken(json);
+
+        // Act
+        var resultToken = A2AContinuationToken.FromToken(mockToken);
+
+        // Assert
+        Assert.Equal(TaskId, resultToken.TaskId);
+    }
+
+    /// <summary>
+    /// Mock implementation of ResponseContinuationToken for testing.
+    /// </summary>
+    private sealed class MockResponseContinuationToken : ResponseContinuationToken
+    {
+        private readonly ReadOnlyMemory<byte> _data;
+
+        public MockResponseContinuationToken(ReadOnlyMemory<byte> data)
+        {
+            this._data = data;
+        }
+
+        public override ReadOnlyMemory<byte> ToBytes()
+        {
+            return this._data;
+        }
+    }
+}